root/magick/effect.c

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DEFINITIONS

This source file includes following definitions.
  1. AdaptiveBlurImage
  2. AdaptiveBlurImageChannel
  3. AdaptiveSharpenImage
  4. AdaptiveSharpenImageChannel
  5. BlurImage
  6. GetBlurKernel
  7. BlurImageChannel
  8. ConvolveImage
  9. ConvolveImageChannel
  10. Hull
  11. DespeckleImage
  12. EdgeImage
  13. EmbossImage
  14. FilterImage
  15. FilterImageChannel
  16. GaussianBlurImage
  17. GaussianBlurImageChannel
  18. GetMotionBlurKernel
  19. MotionBlurImage
  20. MotionBlurImageChannel
  21. PreviewImage
  22. RadialBlurImage
  23. RadialBlurImageChannel
  24. SelectiveContrast
  25. SelectiveBlurImage
  26. SelectiveBlurImageChannel
  27. ShadeImage
  28. SharpenImage
  29. SharpenImageChannel
  30. SpreadImage
  31. DestroyPixelList
  32. DestroyPixelListThreadSet
  33. AcquirePixelList
  34. AcquirePixelListThreadSet
  35. AddNodePixelList
  36. GetMaximumPixelList
  37. GetMeanPixelList
  38. GetMedianPixelList
  39. GetMinimumPixelList
  40. GetModePixelList
  41. GetNonpeakPixelList
  42. GetStandardDeviationPixelList
  43. InsertPixelList
  44. MagickAbsoluteValue
  45. ResetPixelList
  46. StatisticImage
  47. StatisticImageChannel
  48. UnsharpMaskImage
  49. UnsharpMaskImageChannel

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%                   EEEEE  FFFFF  FFFFF  EEEEE  CCCC  TTTTT                   %
%                   E      F      F      E     C        T                     %
%                   EEE    FFF    FFF    EEE   C        T                     %
%                   E      F      F      E     C        T                     %
%                   EEEEE  F      F      EEEEE  CCCC    T                     %
%                                                                             %
%                                                                             %
%                       MagickCore Image Effects Methods                      %
%                                                                             %
%                               Software Design                               %
%                                 John Cristy                                 %
%                                 October 1996                                %
%                                                                             %
%                                                                             %
%  Copyright 1999-2011 ImageMagick Studio LLC, a non-profit organization      %
%  dedicated to making software imaging solutions freely available.           %
%                                                                             %
%  You may not use this file except in compliance with the License.  You may  %
%  obtain a copy of the License at                                            %
%                                                                             %
%    http://www.imagemagick.org/script/license.php                            %
%                                                                             %
%  Unless required by applicable law or agreed to in writing, software        %
%  distributed under the License is distributed on an "AS IS" BASIS,          %
%  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   %
%  See the License for the specific language governing permissions and        %
%  limitations under the License.                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%
%
*/

/*
  Include declarations.
*/
#include "magick/studio.h"
#include "magick/accelerate.h"
#include "magick/blob.h"
#include "magick/cache-view.h"
#include "magick/color.h"
#include "magick/color-private.h"
#include "magick/colorspace.h"
#include "magick/constitute.h"
#include "magick/decorate.h"
#include "magick/draw.h"
#include "magick/enhance.h"
#include "magick/exception.h"
#include "magick/exception-private.h"
#include "magick/effect.h"
#include "magick/fx.h"
#include "magick/gem.h"
#include "magick/geometry.h"
#include "magick/image-private.h"
#include "magick/list.h"
#include "magick/log.h"
#include "magick/memory_.h"
#include "magick/monitor.h"
#include "magick/monitor-private.h"
#include "magick/montage.h"
#include "magick/morphology.h"
#include "magick/paint.h"
#include "magick/pixel-private.h"
#include "magick/property.h"
#include "magick/quantize.h"
#include "magick/quantum.h"
#include "magick/random_.h"
#include "magick/random-private.h"
#include "magick/resample.h"
#include "magick/resample-private.h"
#include "magick/resize.h"
#include "magick/resource_.h"
#include "magick/segment.h"
#include "magick/shear.h"
#include "magick/signature-private.h"
#include "magick/string_.h"
#include "magick/thread-private.h"
#include "magick/transform.h"
#include "magick/threshold.h"

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     A d a p t i v e B l u r I m a g e                                       %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  AdaptiveBlurImage() adaptively blurs the image by blurring less
%  intensely near image edges and more intensely far from edges.  We blur the
%  image with a Gaussian operator of the given radius and standard deviation
%  (sigma).  For reasonable results, radius should be larger than sigma.  Use a
%  radius of 0 and AdaptiveBlurImage() selects a suitable radius for you.
%
%  The format of the AdaptiveBlurImage method is:
%
%      Image *AdaptiveBlurImage(const Image *image,const double radius,
%        const double sigma,ExceptionInfo *exception)
%      Image *AdaptiveBlurImageChannel(const Image *image,
%        const ChannelType channel,double radius,const double sigma,
%        ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: the channel type.
%
%    o radius: the radius of the Gaussian, in pixels, not counting the center
%      pixel.
%
%    o sigma: the standard deviation of the Laplacian, in pixels.
%
%    o exception: return any errors or warnings in this structure.
%
*/

MagickExport Image *AdaptiveBlurImage(const Image *image,const double radius,
  const double sigma,ExceptionInfo *exception)
{
  Image
    *blur_image;

  blur_image=AdaptiveBlurImageChannel(image,DefaultChannels,radius,sigma,
    exception);
  return(blur_image);
}

MagickExport Image *AdaptiveBlurImageChannel(const Image *image,
  const ChannelType channel,const double radius,const double sigma,
  ExceptionInfo *exception)
{
#define AdaptiveBlurImageTag  "Convolve/Image"
#define MagickSigma  (fabs(sigma) <= MagickEpsilon ? 1.0 : sigma)

  CacheView
    *blur_view,
    *edge_view,
    *image_view;

  double
    **kernel,
    normalize;

  Image
    *blur_image,
    *edge_image,
    *gaussian_image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  MagickPixelPacket
    bias;

  register ssize_t
    i;

  size_t
    width;

  ssize_t
    j,
    k,
    u,
    v,
    y;

  assert(image != (const Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  blur_image=CloneImage(image,image->columns,image->rows,MagickTrue,exception);
  if (blur_image == (Image *) NULL)
    return((Image *) NULL);
  if (fabs(sigma) <= MagickEpsilon)
    return(blur_image);
  if (SetImageStorageClass(blur_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&blur_image->exception);
      blur_image=DestroyImage(blur_image);
      return((Image *) NULL);
    }
  /*
    Edge detect the image brighness channel, level, blur, and level again.
  */
  edge_image=EdgeImage(image,radius,exception);
  if (edge_image == (Image *) NULL)
    {
      blur_image=DestroyImage(blur_image);
      return((Image *) NULL);
    }
  (void) LevelImage(edge_image,"20%,95%");
  gaussian_image=GaussianBlurImage(edge_image,radius,sigma,exception);
  if (gaussian_image != (Image *) NULL)
    {
      edge_image=DestroyImage(edge_image);
      edge_image=gaussian_image;
    }
  (void) LevelImage(edge_image,"10%,95%");
  /*
    Create a set of kernels from maximum (radius,sigma) to minimum.
  */
  width=GetOptimalKernelWidth2D(radius,sigma);
  kernel=(double **) AcquireQuantumMemory((size_t) width,sizeof(*kernel));
  if (kernel == (double **) NULL)
    {
      edge_image=DestroyImage(edge_image);
      blur_image=DestroyImage(blur_image);
      ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
    }
  (void) ResetMagickMemory(kernel,0,(size_t) width*sizeof(*kernel));
  for (i=0; i < (ssize_t) width; i+=2)
  {
    kernel[i]=(double *) AcquireQuantumMemory((size_t) (width-i),(width-i)*
      sizeof(**kernel));
    if (kernel[i] == (double *) NULL)
      break;
    normalize=0.0;
    j=(ssize_t) (width-i)/2;
    k=0;
    for (v=(-j); v <= j; v++)
    {
      for (u=(-j); u <= j; u++)
      {
        kernel[i][k]=(double) (exp(-((double) u*u+v*v)/(2.0*MagickSigma*
          MagickSigma))/(2.0*MagickPI*MagickSigma*MagickSigma));
        normalize+=kernel[i][k];
        k++;
      }
    }
    if (fabs(normalize) <= MagickEpsilon)
      normalize=1.0;
    normalize=1.0/normalize;
    for (k=0; k < (j*j); k++)
      kernel[i][k]=normalize*kernel[i][k];
  }
  if (i < (ssize_t) width)
    {
      for (i-=2; i >= 0; i-=2)
        kernel[i]=(double *) RelinquishMagickMemory(kernel[i]);
      kernel=(double **) RelinquishMagickMemory(kernel);
      edge_image=DestroyImage(edge_image);
      blur_image=DestroyImage(blur_image);
      ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
    }
  /*
    Adaptively blur image.
  */
  status=MagickTrue;
  progress=0;
  GetMagickPixelPacket(image,&bias);
  SetMagickPixelPacketBias(image,&bias);
  image_view=AcquireCacheView(image);
  edge_view=AcquireCacheView(edge_image);
  blur_view=AcquireCacheView(blur_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
  for (y=0; y < (ssize_t) blur_image->rows; y++)
  {
    register const IndexPacket
      *restrict indexes;

    register const PixelPacket
      *restrict p,
      *restrict r;

    register IndexPacket
      *restrict blur_indexes;

    register PixelPacket
      *restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    r=GetCacheViewVirtualPixels(edge_view,0,y,edge_image->columns,1,exception);
    q=QueueCacheViewAuthenticPixels(blur_view,0,y,blur_image->columns,1,
      exception);
    if ((r == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
      {
        status=MagickFalse;
        continue;
      }
    blur_indexes=GetCacheViewAuthenticIndexQueue(blur_view);
    for (x=0; x < (ssize_t) blur_image->columns; x++)
    {
      MagickPixelPacket
        pixel;

      MagickRealType
        alpha,
        gamma;

      register const double
        *restrict k;

      register ssize_t
        i,
        u,
        v;

      gamma=0.0;
      i=(ssize_t) ceil((double) width*QuantumScale*PixelIntensity(r)-0.5);
      if (i < 0)
        i=0;
      else
        if (i > (ssize_t) width)
          i=(ssize_t) width;
      if ((i & 0x01) != 0)
        i--;
      p=GetCacheViewVirtualPixels(image_view,x-((ssize_t) (width-i)/2L),y-
        (ssize_t) ((width-i)/2L),width-i,width-i,exception);
      if (p == (const PixelPacket *) NULL)
        break;
      indexes=GetCacheViewVirtualIndexQueue(image_view);
      pixel=bias;
      k=kernel[i];
      for (v=0; v < (ssize_t) (width-i); v++)
      {
        for (u=0; u < (ssize_t) (width-i); u++)
        {
          alpha=1.0;
          if (((channel & OpacityChannel) != 0) &&
              (image->matte != MagickFalse))
            alpha=(MagickRealType) (QuantumScale*GetAlphaPixelComponent(p));
          if ((channel & RedChannel) != 0)
            pixel.red+=(*k)*alpha*GetRedPixelComponent(p);
          if ((channel & GreenChannel) != 0)
            pixel.green+=(*k)*alpha*GetGreenPixelComponent(p);
          if ((channel & BlueChannel) != 0)
            pixel.blue+=(*k)*alpha*GetBluePixelComponent(p);
          if ((channel & OpacityChannel) != 0)
            pixel.opacity+=(*k)*GetOpacityPixelComponent(p);
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            pixel.index+=(*k)*alpha*indexes[x+(width-i)*v+u];
          gamma+=(*k)*alpha;
          k++;
          p++;
        }
      }
      gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
      if ((channel & RedChannel) != 0)
        q->red=ClampToQuantum(gamma*GetRedPixelComponent(&pixel));
      if ((channel & GreenChannel) != 0)
        q->green=ClampToQuantum(gamma*GetGreenPixelComponent(&pixel));
      if ((channel & BlueChannel) != 0)
        q->blue=ClampToQuantum(gamma*GetBluePixelComponent(&pixel));
      if ((channel & OpacityChannel) != 0)
        SetOpacityPixelComponent(q,ClampOpacityPixelComponent(&pixel));
      if (((channel & IndexChannel) != 0) &&
          (image->colorspace == CMYKColorspace))
        blur_indexes[x]=ClampToQuantum(gamma*GetIndexPixelComponent(&pixel));
      q++;
      r++;
    }
    if (SyncCacheViewAuthenticPixels(blur_view,exception) == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_AdaptiveBlurImageChannel)
#endif
        proceed=SetImageProgress(image,AdaptiveBlurImageTag,progress++,
          image->rows);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  blur_image->type=image->type;
  blur_view=DestroyCacheView(blur_view);
  edge_view=DestroyCacheView(edge_view);
  image_view=DestroyCacheView(image_view);
  edge_image=DestroyImage(edge_image);
  for (i=0; i < (ssize_t) width;  i+=2)
    kernel[i]=(double *) RelinquishMagickMemory(kernel[i]);
  kernel=(double **) RelinquishMagickMemory(kernel);
  if (status == MagickFalse)
    blur_image=DestroyImage(blur_image);
  return(blur_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     A d a p t i v e S h a r p e n I m a g e                                 %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  AdaptiveSharpenImage() adaptively sharpens the image by sharpening more
%  intensely near image edges and less intensely far from edges. We sharpen the
%  image with a Gaussian operator of the given radius and standard deviation
%  (sigma).  For reasonable results, radius should be larger than sigma.  Use a
%  radius of 0 and AdaptiveSharpenImage() selects a suitable radius for you.
%
%  The format of the AdaptiveSharpenImage method is:
%
%      Image *AdaptiveSharpenImage(const Image *image,const double radius,
%        const double sigma,ExceptionInfo *exception)
%      Image *AdaptiveSharpenImageChannel(const Image *image,
%        const ChannelType channel,double radius,const double sigma,
%        ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: the channel type.
%
%    o radius: the radius of the Gaussian, in pixels, not counting the center
%      pixel.
%
%    o sigma: the standard deviation of the Laplacian, in pixels.
%
%    o exception: return any errors or warnings in this structure.
%
*/

MagickExport Image *AdaptiveSharpenImage(const Image *image,const double radius,
  const double sigma,ExceptionInfo *exception)
{
  Image
    *sharp_image;

  sharp_image=AdaptiveSharpenImageChannel(image,DefaultChannels,radius,sigma,
    exception);
  return(sharp_image);
}

MagickExport Image *AdaptiveSharpenImageChannel(const Image *image,
  const ChannelType channel,const double radius,const double sigma,
  ExceptionInfo *exception)
{
#define AdaptiveSharpenImageTag  "Convolve/Image"
#define MagickSigma  (fabs(sigma) <= MagickEpsilon ? 1.0 : sigma)

  CacheView
    *sharp_view,
    *edge_view,
    *image_view;

  double
    **kernel,
    normalize;

  Image
    *sharp_image,
    *edge_image,
    *gaussian_image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  MagickPixelPacket
    bias;

  register ssize_t
    i;

  size_t
    width;

  ssize_t
    j,
    k,
    u,
    v,
    y;

  assert(image != (const Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  sharp_image=CloneImage(image,0,0,MagickTrue,exception);
  if (sharp_image == (Image *) NULL)
    return((Image *) NULL);
  if (fabs(sigma) <= MagickEpsilon)
    return(sharp_image);
  if (SetImageStorageClass(sharp_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&sharp_image->exception);
      sharp_image=DestroyImage(sharp_image);
      return((Image *) NULL);
    }
  /*
    Edge detect the image brighness channel, level, sharp, and level again.
  */
  edge_image=EdgeImage(image,radius,exception);
  if (edge_image == (Image *) NULL)
    {
      sharp_image=DestroyImage(sharp_image);
      return((Image *) NULL);
    }
  (void) LevelImage(edge_image,"20%,95%");
  gaussian_image=GaussianBlurImage(edge_image,radius,sigma,exception);
  if (gaussian_image != (Image *) NULL)
    {
      edge_image=DestroyImage(edge_image);
      edge_image=gaussian_image;
    }
  (void) LevelImage(edge_image,"10%,95%");
  /*
    Create a set of kernels from maximum (radius,sigma) to minimum.
  */
  width=GetOptimalKernelWidth2D(radius,sigma);
  kernel=(double **) AcquireQuantumMemory((size_t) width,sizeof(*kernel));
  if (kernel == (double **) NULL)
    {
      edge_image=DestroyImage(edge_image);
      sharp_image=DestroyImage(sharp_image);
      ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
    }
  (void) ResetMagickMemory(kernel,0,(size_t) width*sizeof(*kernel));
  for (i=0; i < (ssize_t) width; i+=2)
  {
    kernel[i]=(double *) AcquireQuantumMemory((size_t) (width-i),(width-i)*
      sizeof(**kernel));
    if (kernel[i] == (double *) NULL)
      break;
    normalize=0.0;
    j=(ssize_t) (width-i)/2;
    k=0;
    for (v=(-j); v <= j; v++)
    {
      for (u=(-j); u <= j; u++)
      {
        kernel[i][k]=(double) (-exp(-((double) u*u+v*v)/(2.0*MagickSigma*
          MagickSigma))/(2.0*MagickPI*MagickSigma*MagickSigma));
        normalize+=kernel[i][k];
        k++;
      }
    }
    if (fabs(normalize) <= MagickEpsilon)
      normalize=1.0;
    normalize=1.0/normalize;
    for (k=0; k < (j*j); k++)
      kernel[i][k]=normalize*kernel[i][k];
  }
  if (i < (ssize_t) width)
    {
      for (i-=2; i >= 0; i-=2)
        kernel[i]=(double *) RelinquishMagickMemory(kernel[i]);
      kernel=(double **) RelinquishMagickMemory(kernel);
      edge_image=DestroyImage(edge_image);
      sharp_image=DestroyImage(sharp_image);
      ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
    }
  /*
    Adaptively sharpen image.
  */
  status=MagickTrue;
  progress=0;
  GetMagickPixelPacket(image,&bias);
  SetMagickPixelPacketBias(image,&bias);
  image_view=AcquireCacheView(image);
  edge_view=AcquireCacheView(edge_image);
  sharp_view=AcquireCacheView(sharp_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
  for (y=0; y < (ssize_t) sharp_image->rows; y++)
  {
    register const IndexPacket
      *restrict indexes;

    register const PixelPacket
      *restrict p,
      *restrict r;

    register IndexPacket
      *restrict sharp_indexes;

    register PixelPacket
      *restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    r=GetCacheViewVirtualPixels(edge_view,0,y,edge_image->columns,1,exception);
    q=QueueCacheViewAuthenticPixels(sharp_view,0,y,sharp_image->columns,1,
      exception);
    if ((r == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
      {
        status=MagickFalse;
        continue;
      }
    sharp_indexes=GetCacheViewAuthenticIndexQueue(sharp_view);
    for (x=0; x < (ssize_t) sharp_image->columns; x++)
    {
      MagickPixelPacket
        pixel;

      MagickRealType
        alpha,
        gamma;

      register const double
        *restrict k;

      register ssize_t
        i,
        u,
        v;

      gamma=0.0;
      i=(ssize_t) ceil((double) width*(QuantumRange-QuantumScale*
        PixelIntensity(r))-0.5);
      if (i < 0)
        i=0;
      else
        if (i > (ssize_t) width)
          i=(ssize_t) width;
      if ((i & 0x01) != 0)
        i--;
      p=GetCacheViewVirtualPixels(image_view,x-((ssize_t) (width-i)/2L),y-
        (ssize_t) ((width-i)/2L),width-i,width-i,exception);
      if (p == (const PixelPacket *) NULL)
        break;
      indexes=GetCacheViewVirtualIndexQueue(image_view);
      k=kernel[i];
      pixel=bias;
      for (v=0; v < (ssize_t) (width-i); v++)
      {
        for (u=0; u < (ssize_t) (width-i); u++)
        {
          alpha=1.0;
          if (((channel & OpacityChannel) != 0) &&
              (image->matte != MagickFalse))
            alpha=(MagickRealType) (QuantumScale*GetAlphaPixelComponent(p));
          if ((channel & RedChannel) != 0)
            pixel.red+=(*k)*alpha*GetRedPixelComponent(p);
          if ((channel & GreenChannel) != 0)
            pixel.green+=(*k)*alpha*GetGreenPixelComponent(p);
          if ((channel & BlueChannel) != 0)
            pixel.blue+=(*k)*alpha*GetBluePixelComponent(p);
          if ((channel & OpacityChannel) != 0)
            pixel.opacity+=(*k)*GetOpacityPixelComponent(p);
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            pixel.index+=(*k)*alpha*indexes[x+(width-i)*v+u];
          gamma+=(*k)*alpha;
          k++;
          p++;
        }
      }
      gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
      if ((channel & RedChannel) != 0)
        q->red=ClampToQuantum(gamma*GetRedPixelComponent(&pixel));
      if ((channel & GreenChannel) != 0)
        q->green=ClampToQuantum(gamma*GetGreenPixelComponent(&pixel));
      if ((channel & BlueChannel) != 0)
        q->blue=ClampToQuantum(gamma*GetBluePixelComponent(&pixel));
      if ((channel & OpacityChannel) != 0)
        SetOpacityPixelComponent(q,ClampOpacityPixelComponent(&pixel));
      if (((channel & IndexChannel) != 0) &&
          (image->colorspace == CMYKColorspace))
        sharp_indexes[x]=ClampToQuantum(gamma*GetIndexPixelComponent(&pixel));
      q++;
      r++;
    }
    if (SyncCacheViewAuthenticPixels(sharp_view,exception) == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_AdaptiveSharpenImageChannel)
#endif
        proceed=SetImageProgress(image,AdaptiveSharpenImageTag,progress++,
          image->rows);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  sharp_image->type=image->type;
  sharp_view=DestroyCacheView(sharp_view);
  edge_view=DestroyCacheView(edge_view);
  image_view=DestroyCacheView(image_view);
  edge_image=DestroyImage(edge_image);
  for (i=0; i < (ssize_t) width;  i+=2)
    kernel[i]=(double *) RelinquishMagickMemory(kernel[i]);
  kernel=(double **) RelinquishMagickMemory(kernel);
  if (status == MagickFalse)
    sharp_image=DestroyImage(sharp_image);
  return(sharp_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     B l u r I m a g e                                                       %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  BlurImage() blurs an image.  We convolve the image with a Gaussian operator
%  of the given radius and standard deviation (sigma).  For reasonable results,
%  the radius should be larger than sigma.  Use a radius of 0 and BlurImage()
%  selects a suitable radius for you.
%
%  BlurImage() differs from GaussianBlurImage() in that it uses a separable
%  kernel which is faster but mathematically equivalent to the non-separable
%  kernel.
%
%  The format of the BlurImage method is:
%
%      Image *BlurImage(const Image *image,const double radius,
%        const double sigma,ExceptionInfo *exception)
%      Image *BlurImageChannel(const Image *image,const ChannelType channel,
%        const double radius,const double sigma,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: the channel type.
%
%    o radius: the radius of the Gaussian, in pixels, not counting the center
%      pixel.
%
%    o sigma: the standard deviation of the Gaussian, in pixels.
%
%    o exception: return any errors or warnings in this structure.
%
*/

MagickExport Image *BlurImage(const Image *image,const double radius,
  const double sigma,ExceptionInfo *exception)
{
  Image
    *blur_image;

  blur_image=BlurImageChannel(image,DefaultChannels,radius,sigma,exception);
  return(blur_image);
}

static double *GetBlurKernel(const size_t width,const double sigma)
{
  double
    *kernel,
    normalize;

  register ssize_t
    i;

  ssize_t
    j,
    k;

  /*
    Generate a 1-D convolution kernel.
  */
  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"...");
  kernel=(double *) AcquireQuantumMemory((size_t) width,sizeof(*kernel));
  if (kernel == (double *) NULL)
    return(0);
  normalize=0.0;
  j=(ssize_t) width/2;
  i=0;
  for (k=(-j); k <= j; k++)
  {
    kernel[i]=(double) (exp(-((double) k*k)/(2.0*MagickSigma*MagickSigma))/
      (MagickSQ2PI*MagickSigma));
    normalize+=kernel[i];
    i++;
  }
  for (i=0; i < (ssize_t) width; i++)
    kernel[i]/=normalize;
  return(kernel);
}

MagickExport Image *BlurImageChannel(const Image *image,
  const ChannelType channel,const double radius,const double sigma,
  ExceptionInfo *exception)
{
#define BlurImageTag  "Blur/Image"

  CacheView
    *blur_view,
    *image_view;

  double
    *kernel;

  Image
    *blur_image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  MagickPixelPacket
    bias;

  register ssize_t
    i;

  size_t
    width;

  ssize_t
    x,
    y;

  /*
    Initialize blur image attributes.
  */
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  blur_image=CloneImage(image,0,0,MagickTrue,exception);
  if (blur_image == (Image *) NULL)
    return((Image *) NULL);
  if (fabs(sigma) <= MagickEpsilon)
    return(blur_image);
  if (SetImageStorageClass(blur_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&blur_image->exception);
      blur_image=DestroyImage(blur_image);
      return((Image *) NULL);
    }
  width=GetOptimalKernelWidth1D(radius,sigma);
  kernel=GetBlurKernel(width,sigma);
  if (kernel == (double *) NULL)
    {
      blur_image=DestroyImage(blur_image);
      ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
    }
  if (image->debug != MagickFalse)
    {
      char
        format[MaxTextExtent],
        *message;

      register const double
        *k;

      (void) LogMagickEvent(TransformEvent,GetMagickModule(),
        "  BlurImage with %.20g kernel:",(double) width);
      message=AcquireString("");
      k=kernel;
      for (i=0; i < (ssize_t) width; i++)
      {
        *message='\0';
        (void) FormatMagickString(format,MaxTextExtent,"%.20g: ",(double) i);
        (void) ConcatenateString(&message,format);
        (void) FormatMagickString(format,MaxTextExtent,"%g ",*k++);
        (void) ConcatenateString(&message,format);
        (void) LogMagickEvent(TransformEvent,GetMagickModule(),"%s",message);
      }
      message=DestroyString(message);
    }
  /*
    Blur rows.
  */
  status=MagickTrue;
  progress=0;
  GetMagickPixelPacket(image,&bias);
  SetMagickPixelPacketBias(image,&bias);
  image_view=AcquireCacheView(image);
  blur_view=AcquireCacheView(blur_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
  for (y=0; y < (ssize_t) blur_image->rows; y++)
  {
    register const IndexPacket
      *restrict indexes;

    register const PixelPacket
      *restrict p;

    register IndexPacket
      *restrict blur_indexes;

    register PixelPacket
      *restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    p=GetCacheViewVirtualPixels(image_view,-((ssize_t) width/2L),y,
      image->columns+width,1,exception);
    q=GetCacheViewAuthenticPixels(blur_view,0,y,blur_image->columns,1,
      exception);
    if ((p == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
      {
        status=MagickFalse;
        continue;
      }
    indexes=GetCacheViewVirtualIndexQueue(image_view);
    blur_indexes=GetCacheViewAuthenticIndexQueue(blur_view);
    for (x=0; x < (ssize_t) blur_image->columns; x++)
    {
      MagickPixelPacket
        pixel;

      register const double
        *restrict k;

      register const PixelPacket
        *restrict kernel_pixels;

      register ssize_t
        i;

      pixel=bias;
      k=kernel;
      kernel_pixels=p;
      if (((channel & OpacityChannel) == 0) || (image->matte == MagickFalse))
        {
          for (i=0; i < (ssize_t) width; i++)
          {
            pixel.red+=(*k)*kernel_pixels->red;
            pixel.green+=(*k)*kernel_pixels->green;
            pixel.blue+=(*k)*kernel_pixels->blue;
            k++;
            kernel_pixels++;
          }
          if ((channel & RedChannel) != 0)
            SetRedPixelComponent(q,ClampRedPixelComponent(&pixel));
          if ((channel & GreenChannel) != 0)
            SetGreenPixelComponent(q,ClampGreenPixelComponent(&pixel));
          if ((channel & BlueChannel) != 0)
            SetBluePixelComponent(q,ClampBluePixelComponent(&pixel));
          if ((channel & OpacityChannel) != 0)
            {
              k=kernel;
              kernel_pixels=p;
              for (i=0; i < (ssize_t) width; i++)
              {
                pixel.opacity+=(*k)*kernel_pixels->opacity;
                k++;
                kernel_pixels++;
              }
              SetOpacityPixelComponent(q,ClampOpacityPixelComponent(&pixel));
            }
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            {
              register const IndexPacket
                *restrict kernel_indexes;

              k=kernel;
              kernel_indexes=indexes;
              for (i=0; i < (ssize_t) width; i++)
              {
                pixel.index+=(*k)*(*kernel_indexes);
                k++;
                kernel_indexes++;
              }
              blur_indexes[x]=ClampToQuantum(pixel.index);
            }
        }
      else
        {
          MagickRealType
            alpha,
            gamma;

          gamma=0.0;
          for (i=0; i < (ssize_t) width; i++)
          {
            alpha=(MagickRealType) (QuantumScale*
              GetAlphaPixelComponent(kernel_pixels));
            pixel.red+=(*k)*alpha*kernel_pixels->red;
            pixel.green+=(*k)*alpha*kernel_pixels->green;
            pixel.blue+=(*k)*alpha*kernel_pixels->blue;
            gamma+=(*k)*alpha;
            k++;
            kernel_pixels++;
          }
          gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
          if ((channel & RedChannel) != 0)
            q->red=ClampToQuantum(gamma*GetRedPixelComponent(&pixel));
          if ((channel & GreenChannel) != 0)
            q->green=ClampToQuantum(gamma*GetGreenPixelComponent(&pixel));
          if ((channel & BlueChannel) != 0)
            q->blue=ClampToQuantum(gamma*GetBluePixelComponent(&pixel));
          if ((channel & OpacityChannel) != 0)
            {
              k=kernel;
              kernel_pixels=p;
              for (i=0; i < (ssize_t) width; i++)
              {
                pixel.opacity+=(*k)*kernel_pixels->opacity;
                k++;
                kernel_pixels++;
              }
              SetOpacityPixelComponent(q,ClampOpacityPixelComponent(&pixel));
            }
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            {
              register const IndexPacket
                *restrict kernel_indexes;

              k=kernel;
              kernel_pixels=p;
              kernel_indexes=indexes;
              for (i=0; i < (ssize_t) width; i++)
              {
                alpha=(MagickRealType) (QuantumScale*
                  GetAlphaPixelComponent(kernel_pixels));
                pixel.index+=(*k)*alpha*(*kernel_indexes);
                k++;
                kernel_pixels++;
                kernel_indexes++;
              }
              blur_indexes[x]=ClampToQuantum(gamma*
                GetIndexPixelComponent(&pixel));
            }
        }
      indexes++;
      p++;
      q++;
    }
    if (SyncCacheViewAuthenticPixels(blur_view,exception) == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_BlurImageChannel)
#endif
        proceed=SetImageProgress(image,BlurImageTag,progress++,blur_image->rows+
          blur_image->columns);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  blur_view=DestroyCacheView(blur_view);
  image_view=DestroyCacheView(image_view);
  /*
    Blur columns.
  */
  image_view=AcquireCacheView(blur_image);
  blur_view=AcquireCacheView(blur_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
  for (x=0; x < (ssize_t) blur_image->columns; x++)
  {
    register const IndexPacket
      *restrict indexes;

    register const PixelPacket
      *restrict p;

    register IndexPacket
      *restrict blur_indexes;

    register PixelPacket
      *restrict q;

    register ssize_t
      y;

    if (status == MagickFalse)
      continue;
    p=GetCacheViewVirtualPixels(image_view,x,-((ssize_t) width/2L),1,
      image->rows+width,exception);
    q=GetCacheViewAuthenticPixels(blur_view,x,0,1,blur_image->rows,exception);
    if ((p == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
      {
        status=MagickFalse;
        continue;
      }
    indexes=GetCacheViewVirtualIndexQueue(image_view);
    blur_indexes=GetCacheViewAuthenticIndexQueue(blur_view);
    for (y=0; y < (ssize_t) blur_image->rows; y++)
    {
      MagickPixelPacket
        pixel;

      register const double
        *restrict k;

      register const PixelPacket
        *restrict kernel_pixels;

      register ssize_t
        i;

      pixel=bias;
      k=kernel;
      kernel_pixels=p;
      if (((channel & OpacityChannel) == 0) || (image->matte == MagickFalse))
        {
          for (i=0; i < (ssize_t) width; i++)
          {
            pixel.red+=(*k)*kernel_pixels->red;
            pixel.green+=(*k)*kernel_pixels->green;
            pixel.blue+=(*k)*kernel_pixels->blue;
            k++;
            kernel_pixels++;
          }
          if ((channel & RedChannel) != 0)
            SetRedPixelComponent(q,ClampRedPixelComponent(&pixel));
          if ((channel & GreenChannel) != 0)
            SetGreenPixelComponent(q,ClampGreenPixelComponent(&pixel));
          if ((channel & BlueChannel) != 0)
            SetBluePixelComponent(q,ClampBluePixelComponent(&pixel));
          if ((channel & OpacityChannel) != 0)
            {
              k=kernel;
              kernel_pixels=p;
              for (i=0; i < (ssize_t) width; i++)
              {
                pixel.opacity+=(*k)*kernel_pixels->opacity;
                k++;
                kernel_pixels++;
              }
              SetOpacityPixelComponent(q,ClampOpacityPixelComponent(&pixel));
            }
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            {
              register const IndexPacket
                *restrict kernel_indexes;

              k=kernel;
              kernel_indexes=indexes;
              for (i=0; i < (ssize_t) width; i++)
              {
                pixel.index+=(*k)*(*kernel_indexes);
                k++;
                kernel_indexes++;
              }
              blur_indexes[y]=ClampToQuantum(pixel.index);
            }
        }
      else
        {
          MagickRealType
            alpha,
            gamma;

          gamma=0.0;
          for (i=0; i < (ssize_t) width; i++)
          {
            alpha=(MagickRealType) (QuantumScale*
              GetAlphaPixelComponent(kernel_pixels));
            pixel.red+=(*k)*alpha*kernel_pixels->red;
            pixel.green+=(*k)*alpha*kernel_pixels->green;
            pixel.blue+=(*k)*alpha*kernel_pixels->blue;
            gamma+=(*k)*alpha;
            k++;
            kernel_pixels++;
          }
          gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
          if ((channel & RedChannel) != 0)
            q->red=ClampToQuantum(gamma*GetRedPixelComponent(&pixel));
          if ((channel & GreenChannel) != 0)
            q->green=ClampToQuantum(gamma*GetGreenPixelComponent(&pixel));
          if ((channel & BlueChannel) != 0)
            q->blue=ClampToQuantum(gamma*GetBluePixelComponent(&pixel));
          if ((channel & OpacityChannel) != 0)
            {
              k=kernel;
              kernel_pixels=p;
              for (i=0; i < (ssize_t) width; i++)
              {
                pixel.opacity+=(*k)*kernel_pixels->opacity;
                k++;
                kernel_pixels++;
              }
              SetOpacityPixelComponent(q,ClampOpacityPixelComponent(&pixel));
            }
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            {
              register const IndexPacket
                *restrict kernel_indexes;

              k=kernel;
              kernel_pixels=p;
              kernel_indexes=indexes;
              for (i=0; i < (ssize_t) width; i++)
              {
                alpha=(MagickRealType) (QuantumScale*
                  GetAlphaPixelComponent(kernel_pixels));
                pixel.index+=(*k)*alpha*(*kernel_indexes);
                k++;
                kernel_pixels++;
                kernel_indexes++;
              }
              blur_indexes[y]=ClampToQuantum(gamma*
                GetIndexPixelComponent(&pixel));
            }
        }
      indexes++;
      p++;
      q++;
    }
    if (SyncCacheViewAuthenticPixels(blur_view,exception) == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_BlurImageChannel)
#endif
        proceed=SetImageProgress(image,BlurImageTag,progress++,blur_image->rows+
          blur_image->columns);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  blur_view=DestroyCacheView(blur_view);
  image_view=DestroyCacheView(image_view);
  kernel=(double *) RelinquishMagickMemory(kernel);
  if (status == MagickFalse)
    blur_image=DestroyImage(blur_image);
  blur_image->type=image->type;
  return(blur_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     C o n v o l v e I m a g e                                               %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  ConvolveImage() applies a custom convolution kernel to the image.
%
%  The format of the ConvolveImage method is:
%
%      Image *ConvolveImage(const Image *image,const size_t order,
%        const double *kernel,ExceptionInfo *exception)
%      Image *ConvolveImageChannel(const Image *image,const ChannelType channel,
%        const size_t order,const double *kernel,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: the channel type.
%
%    o order: the number of columns and rows in the filter kernel.
%
%    o kernel: An array of double representing the convolution kernel.
%
%    o exception: return any errors or warnings in this structure.
%
*/

MagickExport Image *ConvolveImage(const Image *image,const size_t order,
  const double *kernel,ExceptionInfo *exception)
{
  Image
    *convolve_image;

  convolve_image=ConvolveImageChannel(image,DefaultChannels,order,kernel,
    exception);
  return(convolve_image);
}

MagickExport Image *ConvolveImageChannel(const Image *image,
  const ChannelType channel,const size_t order,const double *kernel,
  ExceptionInfo *exception)
{
#define ConvolveImageTag  "Convolve/Image"

  CacheView
    *convolve_view,
    *image_view;

  double
    *normal_kernel;

  Image
    *convolve_image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  MagickPixelPacket
    bias;

  MagickRealType
    gamma;

  register ssize_t
    i;

  size_t
    width;

  ssize_t
    y;

  /*
    Initialize convolve image attributes.
  */
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  width=order;
  if ((width % 2) == 0)
    ThrowImageException(OptionError,"KernelWidthMustBeAnOddNumber");
  convolve_image=CloneImage(image,0,0,MagickTrue,exception);
  if (convolve_image == (Image *) NULL)
    return((Image *) NULL);
  if (SetImageStorageClass(convolve_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&convolve_image->exception);
      convolve_image=DestroyImage(convolve_image);
      return((Image *) NULL);
    }
  if (image->debug != MagickFalse)
    {
      char
        format[MaxTextExtent],
        *message;

      register const double
        *k;

      ssize_t
        u,
        v;

      (void) LogMagickEvent(TransformEvent,GetMagickModule(),
        "  ConvolveImage with %.20gx%.20g kernel:",(double) width,(double)
        width);
      message=AcquireString("");
      k=kernel;
      for (v=0; v < (ssize_t) width; v++)
      {
        *message='\0';
        (void) FormatMagickString(format,MaxTextExtent,"%.20g: ",(double) v);
        (void) ConcatenateString(&message,format);
        for (u=0; u < (ssize_t) width; u++)
        {
          (void) FormatMagickString(format,MaxTextExtent,"%g ",*k++);
          (void) ConcatenateString(&message,format);
        }
        (void) LogMagickEvent(TransformEvent,GetMagickModule(),"%s",message);
      }
      message=DestroyString(message);
    }
  /*
    Normalize kernel.
  */
  normal_kernel=(double *) AcquireQuantumMemory(width*width,
    sizeof(*normal_kernel));
  if (normal_kernel == (double *) NULL)
    {
      convolve_image=DestroyImage(convolve_image);
      ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
    }
  gamma=0.0;
  for (i=0; i < (ssize_t) (width*width); i++)
    gamma+=kernel[i];
  gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
  for (i=0; i < (ssize_t) (width*width); i++)
    normal_kernel[i]=gamma*kernel[i];
  /*
    Convolve image.
  */
  status=MagickTrue;
  progress=0;
  GetMagickPixelPacket(image,&bias);
  SetMagickPixelPacketBias(image,&bias);
  image_view=AcquireCacheView(image);
  convolve_view=AcquireCacheView(convolve_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
  for (y=0; y < (ssize_t) image->rows; y++)
  {
    MagickBooleanType
      sync;

    register const IndexPacket
      *restrict indexes;

    register const PixelPacket
      *restrict p;

    register IndexPacket
      *restrict convolve_indexes;

    register PixelPacket
      *restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    p=GetCacheViewVirtualPixels(image_view,-((ssize_t) width/2L),y-(ssize_t)
      (width/2L),image->columns+width,width,exception);
    q=GetCacheViewAuthenticPixels(convolve_view,0,y,convolve_image->columns,1,
      exception);
    if ((p == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
      {
        status=MagickFalse;
        continue;
      }
    indexes=GetCacheViewVirtualIndexQueue(image_view);
    convolve_indexes=GetCacheViewAuthenticIndexQueue(convolve_view);
    for (x=0; x < (ssize_t) image->columns; x++)
    {
      MagickPixelPacket
        pixel;

      register const double
        *restrict k;

      register const PixelPacket
        *restrict kernel_pixels;

      register ssize_t
        u;

      ssize_t
        v;

      pixel=bias;
      k=normal_kernel;
      kernel_pixels=p;
      if (((channel & OpacityChannel) == 0) || (image->matte == MagickFalse))
        {
          for (v=0; v < (ssize_t) width; v++)
          {
            for (u=0; u < (ssize_t) width; u++)
            {
              pixel.red+=(*k)*kernel_pixels[u].red;
              pixel.green+=(*k)*kernel_pixels[u].green;
              pixel.blue+=(*k)*kernel_pixels[u].blue;
              k++;
            }
            kernel_pixels+=image->columns+width;
          }
          if ((channel & RedChannel) != 0)
            SetRedPixelComponent(q,ClampRedPixelComponent(&pixel));
          if ((channel & GreenChannel) != 0)
            SetGreenPixelComponent(q,ClampGreenPixelComponent(&pixel));
          if ((channel & BlueChannel) != 0)
            SetBluePixelComponent(q,ClampBluePixelComponent(&pixel));
          if ((channel & OpacityChannel) != 0)
            {
              k=normal_kernel;
              kernel_pixels=p;
              for (v=0; v < (ssize_t) width; v++)
              {
                for (u=0; u < (ssize_t) width; u++)
                {
                  pixel.opacity+=(*k)*kernel_pixels[u].opacity;
                  k++;
                }
                kernel_pixels+=image->columns+width;
              }
              SetOpacityPixelComponent(q,ClampOpacityPixelComponent(&pixel));
            }
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            {
              register const IndexPacket
                *restrict kernel_indexes;

              k=normal_kernel;
              kernel_indexes=indexes;
              for (v=0; v < (ssize_t) width; v++)
              {
                for (u=0; u < (ssize_t) width; u++)
                {
                  pixel.index+=(*k)*kernel_indexes[u];
                  k++;
                }
                kernel_indexes+=image->columns+width;
              }
              convolve_indexes[x]=ClampToQuantum(pixel.index);
            }
        }
      else
        {
          MagickRealType
            alpha,
            gamma;

          gamma=0.0;
          for (v=0; v < (ssize_t) width; v++)
          {
            for (u=0; u < (ssize_t) width; u++)
            {
              alpha=(MagickRealType) (QuantumScale*(QuantumRange-
                kernel_pixels[u].opacity));
              pixel.red+=(*k)*alpha*kernel_pixels[u].red;
              pixel.green+=(*k)*alpha*kernel_pixels[u].green;
              pixel.blue+=(*k)*alpha*kernel_pixels[u].blue;
              gamma+=(*k)*alpha;
              k++;
            }
            kernel_pixels+=image->columns+width;
          }
          gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
          if ((channel & RedChannel) != 0)
            q->red=ClampToQuantum(gamma*GetRedPixelComponent(&pixel));
          if ((channel & GreenChannel) != 0)
            q->green=ClampToQuantum(gamma*GetGreenPixelComponent(&pixel));
          if ((channel & BlueChannel) != 0)
            q->blue=ClampToQuantum(gamma*GetBluePixelComponent(&pixel));
          if ((channel & OpacityChannel) != 0)
            {
              k=normal_kernel;
              kernel_pixels=p;
              for (v=0; v < (ssize_t) width; v++)
              {
                for (u=0; u < (ssize_t) width; u++)
                {
                  pixel.opacity+=(*k)*kernel_pixels[u].opacity;
                  k++;
                }
                kernel_pixels+=image->columns+width;
              }
              SetOpacityPixelComponent(q,ClampOpacityPixelComponent(&pixel));
            }
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            {
              register const IndexPacket
                *restrict kernel_indexes;

              k=normal_kernel;
              kernel_pixels=p;
              kernel_indexes=indexes;
              for (v=0; v < (ssize_t) width; v++)
              {
                for (u=0; u < (ssize_t) width; u++)
                {
                  alpha=(MagickRealType) (QuantumScale*(QuantumRange-
                    kernel_pixels[u].opacity));
                  pixel.index+=(*k)*alpha*kernel_indexes[u];
                  k++;
                }
                kernel_pixels+=image->columns+width;
                kernel_indexes+=image->columns+width;
              }
              convolve_indexes[x]=ClampToQuantum(gamma*
                GetIndexPixelComponent(&pixel));
            }
        }
      indexes++;
      p++;
      q++;
    }
    sync=SyncCacheViewAuthenticPixels(convolve_view,exception);
    if (sync == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_ConvolveImageChannel)
#endif
        proceed=SetImageProgress(image,ConvolveImageTag,progress++,image->rows);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  convolve_image->type=image->type;
  convolve_view=DestroyCacheView(convolve_view);
  image_view=DestroyCacheView(image_view);
  normal_kernel=(double *) RelinquishMagickMemory(normal_kernel);
  if (status == MagickFalse)
    convolve_image=DestroyImage(convolve_image);
  return(convolve_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     D e s p e c k l e I m a g e                                             %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  DespeckleImage() reduces the speckle noise in an image while perserving the
%  edges of the original image.
%
%  The format of the DespeckleImage method is:
%
%      Image *DespeckleImage(const Image *image,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o exception: return any errors or warnings in this structure.
%
*/

static void Hull(const ssize_t x_offset,const ssize_t y_offset,
  const size_t columns,const size_t rows,Quantum *f,Quantum *g,
  const int polarity)
{
  MagickRealType
    v;

  register Quantum
    *p,
    *q,
    *r,
    *s;

  register ssize_t
    x;

  ssize_t
    y;

  assert(f != (Quantum *) NULL);
  assert(g != (Quantum *) NULL);
  p=f+(columns+2);
  q=g+(columns+2);
  r=p+(y_offset*((ssize_t) columns+2)+x_offset);
  for (y=0; y < (ssize_t) rows; y++)
  {
    p++;
    q++;
    r++;
    if (polarity > 0)
      for (x=(ssize_t) columns; x != 0; x--)
      {
        v=(MagickRealType) (*p);
        if ((MagickRealType) *r >= (v+(MagickRealType) ScaleCharToQuantum(2)))
          v+=ScaleCharToQuantum(1);
        *q=(Quantum) v;
        p++;
        q++;
        r++;
      }
    else
      for (x=(ssize_t) columns; x != 0; x--)
      {
        v=(MagickRealType) (*p);
        if ((MagickRealType) *r <= (v-(MagickRealType) ScaleCharToQuantum(2)))
          v-=(ssize_t) ScaleCharToQuantum(1);
        *q=(Quantum) v;
        p++;
        q++;
        r++;
      }
    p++;
    q++;
    r++;
  }
  p=f+(columns+2);
  q=g+(columns+2);
  r=q+(y_offset*((ssize_t) columns+2)+x_offset);
  s=q-(y_offset*((ssize_t) columns+2)+x_offset);
  for (y=0; y < (ssize_t) rows; y++)
  {
    p++;
    q++;
    r++;
    s++;
    if (polarity > 0)
      for (x=(ssize_t) columns; x != 0; x--)
      {
        v=(MagickRealType) (*q);
        if (((MagickRealType) *s >=
             (v+(MagickRealType) ScaleCharToQuantum(2))) &&
            ((MagickRealType) *r > v))
          v+=ScaleCharToQuantum(1);
        *p=(Quantum) v;
        p++;
        q++;
        r++;
        s++;
      }
    else
      for (x=(ssize_t) columns; x != 0; x--)
      {
        v=(MagickRealType) (*q);
        if (((MagickRealType) *s <=
             (v-(MagickRealType) ScaleCharToQuantum(2))) &&
            ((MagickRealType) *r < v))
          v-=(MagickRealType) ScaleCharToQuantum(1);
        *p=(Quantum) v;
        p++;
        q++;
        r++;
        s++;
      }
    p++;
    q++;
    r++;
    s++;
  }
}

MagickExport Image *DespeckleImage(const Image *image,ExceptionInfo *exception)
{
#define DespeckleImageTag  "Despeckle/Image"

  CacheView
    *despeckle_view,
    *image_view;

  Image
    *despeckle_image;

  MagickBooleanType
    status;

  register ssize_t
    i;

  Quantum
    *restrict buffers,
    *restrict pixels;

  size_t
    length,
    number_channels;

  static const ssize_t
    X[4] = {0, 1, 1,-1},
    Y[4] = {1, 0, 1, 1};

  /*
    Allocate despeckled image.
  */
  assert(image != (const Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  despeckle_image=CloneImage(image,image->columns,image->rows,MagickTrue,
    exception);
  if (despeckle_image == (Image *) NULL)
    return((Image *) NULL);
  if (SetImageStorageClass(despeckle_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&despeckle_image->exception);
      despeckle_image=DestroyImage(despeckle_image);
      return((Image *) NULL);
    }
  /*
    Allocate image buffers.
  */
  length=(size_t) ((image->columns+2)*(image->rows+2));
  pixels=(Quantum *) AcquireQuantumMemory(length,2*sizeof(*pixels));
  buffers=(Quantum *) AcquireQuantumMemory(length,2*sizeof(*pixels));
  if ((pixels == (Quantum *) NULL) || (buffers == (Quantum *) NULL))
    {
      if (buffers != (Quantum *) NULL)
        buffers=(Quantum *) RelinquishMagickMemory(buffers);
      if (pixels != (Quantum *) NULL)
        pixels=(Quantum *) RelinquishMagickMemory(pixels);
      despeckle_image=DestroyImage(despeckle_image);
      ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
    }
  /*
    Reduce speckle in the image.
  */
  status=MagickTrue;
  number_channels=(size_t) (image->colorspace == CMYKColorspace ? 5 : 4);
  image_view=AcquireCacheView(image);
  despeckle_view=AcquireCacheView(despeckle_image);
  for (i=0; i < (ssize_t) number_channels; i++)
  {
    register Quantum
      *buffer,
      *pixel;

    register ssize_t
      k,
      x;

    ssize_t
      j,
      y;

    if (status == MagickFalse)
      continue;
    pixel=pixels;
    (void) ResetMagickMemory(pixel,0,length*sizeof(*pixel));
    buffer=buffers;
    j=(ssize_t) image->columns+2;
    for (y=0; y < (ssize_t) image->rows; y++)
    {
      register const IndexPacket
        *restrict indexes;

      register const PixelPacket
        *restrict p;

      p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
      if (p == (const PixelPacket *) NULL)
        break;
      indexes=GetCacheViewVirtualIndexQueue(image_view);
      j++;
      for (x=0; x < (ssize_t) image->columns; x++)
      {
        switch (i)
        {
          case 0: pixel[j]=GetRedPixelComponent(p); break;
          case 1: pixel[j]=GetGreenPixelComponent(p); break;
          case 2: pixel[j]=GetBluePixelComponent(p); break;
          case 3: pixel[j]=GetOpacityPixelComponent(p); break;
          case 4: pixel[j]=GetBlackPixelComponent(indexes,x); break;
          default: break;
        }
        p++;
        j++;
      }
      j++;
    }
    (void) ResetMagickMemory(buffer,0,length*sizeof(*buffer));
    for (k=0; k < 4; k++)
    {
      Hull(X[k],Y[k],image->columns,image->rows,pixel,buffer,1);
      Hull(-X[k],-Y[k],image->columns,image->rows,pixel,buffer,1);
      Hull(-X[k],-Y[k],image->columns,image->rows,pixel,buffer,-1);
      Hull(X[k],Y[k],image->columns,image->rows,pixel,buffer,-1);
    }
    j=(ssize_t) image->columns+2;
    for (y=0; y < (ssize_t) image->rows; y++)
    {
      MagickBooleanType
        sync;

      register IndexPacket
        *restrict indexes;

      register PixelPacket
        *restrict q;

      q=GetCacheViewAuthenticPixels(despeckle_view,0,y,despeckle_image->columns,
        1,exception);
      if (q == (PixelPacket *) NULL)
        break;
      indexes=GetCacheViewAuthenticIndexQueue(image_view);
      j++;
      for (x=0; x < (ssize_t) image->columns; x++)
      {
        switch (i)
        {
          case 0: q->red=pixel[j]; break;
          case 1: q->green=pixel[j]; break;
          case 2: q->blue=pixel[j]; break;
          case 3: q->opacity=pixel[j]; break;
          case 4: indexes[x]=pixel[j]; break;
          default: break;
        }
        q++;
        j++;
      }
      sync=SyncCacheViewAuthenticPixels(despeckle_view,exception);
      if (sync == MagickFalse)
        {
          status=MagickFalse;
          break;
        }
      j++;
    }
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

        proceed=SetImageProgress(image,DespeckleImageTag,(MagickOffsetType) i,
          number_channels);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  despeckle_view=DestroyCacheView(despeckle_view);
  image_view=DestroyCacheView(image_view);
  buffers=(Quantum *) RelinquishMagickMemory(buffers);
  pixels=(Quantum *) RelinquishMagickMemory(pixels);
  despeckle_image->type=image->type;
  if (status == MagickFalse)
    despeckle_image=DestroyImage(despeckle_image);
  return(despeckle_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     E d g e I m a g e                                                       %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  EdgeImage() finds edges in an image.  Radius defines the radius of the
%  convolution filter.  Use a radius of 0 and EdgeImage() selects a suitable
%  radius for you.
%
%  The format of the EdgeImage method is:
%
%      Image *EdgeImage(const Image *image,const double radius,
%        ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o radius: the radius of the pixel neighborhood.
%
%    o exception: return any errors or warnings in this structure.
%
*/
MagickExport Image *EdgeImage(const Image *image,const double radius,
  ExceptionInfo *exception)
{
  Image
    *edge_image;

  double
    *kernel;

  register ssize_t
    i;

  size_t
    width;

  assert(image != (const Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  width=GetOptimalKernelWidth1D(radius,0.5);
  kernel=(double *) AcquireQuantumMemory((size_t) width,width*sizeof(*kernel));
  if (kernel == (double *) NULL)
    ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
  for (i=0; i < (ssize_t) (width*width); i++)
    kernel[i]=(-1.0);
  kernel[i/2]=(double) (width*width-1.0);
  edge_image=ConvolveImage(image,width,kernel,exception);
  kernel=(double *) RelinquishMagickMemory(kernel);
  return(edge_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     E m b o s s I m a g e                                                   %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  EmbossImage() returns a grayscale image with a three-dimensional effect.
%  We convolve the image with a Gaussian operator of the given radius and
%  standard deviation (sigma).  For reasonable results, radius should be
%  larger than sigma.  Use a radius of 0 and Emboss() selects a suitable
%  radius for you.
%
%  The format of the EmbossImage method is:
%
%      Image *EmbossImage(const Image *image,const double radius,
%        const double sigma,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o radius: the radius of the pixel neighborhood.
%
%    o sigma: the standard deviation of the Gaussian, in pixels.
%
%    o exception: return any errors or warnings in this structure.
%
*/
MagickExport Image *EmbossImage(const Image *image,const double radius,
  const double sigma,ExceptionInfo *exception)
{
  double
    *kernel;

  Image
    *emboss_image;

  register ssize_t
    i;

  size_t
    width;

  ssize_t
    j,
    k,
    u,
    v;

  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  width=GetOptimalKernelWidth2D(radius,sigma);
  kernel=(double *) AcquireQuantumMemory((size_t) width,width*sizeof(*kernel));
  if (kernel == (double *) NULL)
    ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
  j=(ssize_t) width/2;
  k=j;
  i=0;
  for (v=(-j); v <= j; v++)
  {
    for (u=(-j); u <= j; u++)
    {
      kernel[i]=(double) (((u < 0) || (v < 0) ? -8.0 : 8.0)*
        exp(-((double) u*u+v*v)/(2.0*MagickSigma*MagickSigma))/
        (2.0*MagickPI*MagickSigma*MagickSigma));
      if (u != k)
        kernel[i]=0.0;
      i++;
    }
    k--;
  }
  emboss_image=ConvolveImage(image,width,kernel,exception);
  if (emboss_image != (Image *) NULL)
    (void) EqualizeImage(emboss_image);
  kernel=(double *) RelinquishMagickMemory(kernel);
  return(emboss_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     F i l t e r I m a g e                                                   %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  FilterImage() applies a custom convolution kernel to the image.
%
%  The format of the FilterImage method is:
%
%      Image *FilterImage(const Image *image,const KernelInfo *kernel,
%        ExceptionInfo *exception)
%      Image *FilterImageChannel(const Image *image,const ChannelType channel,
%        const KernelInfo *kernel,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: the channel type.
%
%    o kernel: the filtering kernel.
%
%    o exception: return any errors or warnings in this structure.
%
*/

MagickExport Image *FilterImage(const Image *image,const KernelInfo *kernel,
  ExceptionInfo *exception)
{
  Image
    *filter_image;

  filter_image=FilterImageChannel(image,DefaultChannels,kernel,exception);
  return(filter_image);
}

MagickExport Image *FilterImageChannel(const Image *image,
  const ChannelType channel,const KernelInfo *kernel,ExceptionInfo *exception)
{
#define FilterImageTag  "Filter/Image"

  CacheView
    *filter_view,
    *image_view;

  Image
    *filter_image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  MagickPixelPacket
    bias;

  ssize_t
    y;

  /*
    Initialize filter image attributes.
  */
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  if ((kernel->width % 2) == 0)
    ThrowImageException(OptionError,"KernelWidthMustBeAnOddNumber");
  filter_image=CloneImage(image,0,0,MagickTrue,exception);
  if (filter_image == (Image *) NULL)
    return((Image *) NULL);
  if (SetImageStorageClass(filter_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&filter_image->exception);
      filter_image=DestroyImage(filter_image);
      return((Image *) NULL);
    }
  if (image->debug != MagickFalse)
    {
      char
        format[MaxTextExtent],
        *message;

      register const double
        *k;

      ssize_t
        u,
        v;

      (void) LogMagickEvent(TransformEvent,GetMagickModule(),
        "  FilterImage with %.20gx%.20g kernel:",(double) kernel->width,(double)
        kernel->height);
      message=AcquireString("");
      k=kernel->values;
      for (v=0; v < (ssize_t) kernel->height; v++)
      {
        *message='\0';
        (void) FormatMagickString(format,MaxTextExtent,"%.20g: ",(double) v);
        (void) ConcatenateString(&message,format);
        for (u=0; u < (ssize_t) kernel->width; u++)
        {
          (void) FormatMagickString(format,MaxTextExtent,"%g ",*k++);
          (void) ConcatenateString(&message,format);
        }
        (void) LogMagickEvent(TransformEvent,GetMagickModule(),"%s",message);
      }
      message=DestroyString(message);
    }
  status=AccelerateConvolveImage(image,kernel,filter_image,exception);
  if (status == MagickTrue)
    return(filter_image);
  /*
    Filter image.
  */
  status=MagickTrue;
  progress=0;
  GetMagickPixelPacket(image,&bias);
  SetMagickPixelPacketBias(image,&bias);
  image_view=AcquireCacheView(image);
  filter_view=AcquireCacheView(filter_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
  for (y=0; y < (ssize_t) image->rows; y++)
  {
    MagickBooleanType
      sync;

    register const IndexPacket
      *restrict indexes;

    register const PixelPacket
      *restrict p;

    register IndexPacket
      *restrict filter_indexes;

    register PixelPacket
      *restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    p=GetCacheViewVirtualPixels(image_view,-((ssize_t) kernel->width/2L),
      y-(ssize_t) (kernel->height/2L),image->columns+kernel->width,
      kernel->height,exception);
    q=GetCacheViewAuthenticPixels(filter_view,0,y,filter_image->columns,1,
      exception);
    if ((p == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
      {
        status=MagickFalse;
        continue;
      }
    indexes=GetCacheViewVirtualIndexQueue(image_view);
    filter_indexes=GetCacheViewAuthenticIndexQueue(filter_view);
    for (x=0; x < (ssize_t) image->columns; x++)
    {
      MagickPixelPacket
        pixel;

      register const double
        *restrict k;

      register const PixelPacket
        *restrict kernel_pixels;

      register ssize_t
        u;

      ssize_t
        v;

      pixel=bias;
      k=kernel->values;
      kernel_pixels=p;
      if (((channel & OpacityChannel) == 0) || (image->matte == MagickFalse))
        {
          for (v=0; v < (ssize_t) kernel->width; v++)
          {
            for (u=0; u < (ssize_t) kernel->height; u++)
            {
              pixel.red+=(*k)*kernel_pixels[u].red;
              pixel.green+=(*k)*kernel_pixels[u].green;
              pixel.blue+=(*k)*kernel_pixels[u].blue;
              k++;
            }
            kernel_pixels+=image->columns+kernel->width;
          }
          if ((channel & RedChannel) != 0)
            SetRedPixelComponent(q,ClampRedPixelComponent(&pixel));
          if ((channel & GreenChannel) != 0)
            SetGreenPixelComponent(q,ClampGreenPixelComponent(&pixel));
          if ((channel & BlueChannel) != 0)
            SetBluePixelComponent(q,ClampBluePixelComponent(&pixel));
          if ((channel & OpacityChannel) != 0)
            {
              k=kernel->values;
              kernel_pixels=p;
              for (v=0; v < (ssize_t) kernel->width; v++)
              {
                for (u=0; u < (ssize_t) kernel->height; u++)
                {
                  pixel.opacity+=(*k)*kernel_pixels[u].opacity;
                  k++;
                }
                kernel_pixels+=image->columns+kernel->width;
              }
              SetOpacityPixelComponent(q,ClampOpacityPixelComponent(&pixel));
            }
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            {
              register const IndexPacket
                *restrict kernel_indexes;

              k=kernel->values;
              kernel_indexes=indexes;
              for (v=0; v < (ssize_t) kernel->width; v++)
              {
                for (u=0; u < (ssize_t) kernel->height; u++)
                {
                  pixel.index+=(*k)*kernel_indexes[u];
                  k++;
                }
                kernel_indexes+=image->columns+kernel->width;
              }
              filter_indexes[x]=ClampToQuantum(pixel.index);
            }
        }
      else
        {
          MagickRealType
            alpha,
            gamma;

          gamma=0.0;
          for (v=0; v < (ssize_t) kernel->width; v++)
          {
            for (u=0; u < (ssize_t) kernel->height; u++)
            {
              alpha=(MagickRealType) (QuantumScale*(QuantumRange-
                kernel_pixels[u].opacity));
              pixel.red+=(*k)*alpha*kernel_pixels[u].red;
              pixel.green+=(*k)*alpha*kernel_pixels[u].green;
              pixel.blue+=(*k)*alpha*kernel_pixels[u].blue;
              gamma+=(*k)*alpha;
              k++;
            }
            kernel_pixels+=image->columns+kernel->width;
          }
          gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
          if ((channel & RedChannel) != 0)
            q->red=ClampToQuantum(gamma*GetRedPixelComponent(&pixel));
          if ((channel & GreenChannel) != 0)
            q->green=ClampToQuantum(gamma*GetGreenPixelComponent(&pixel));
          if ((channel & BlueChannel) != 0)
            q->blue=ClampToQuantum(gamma*GetBluePixelComponent(&pixel));
          if ((channel & OpacityChannel) != 0)
            {
              k=kernel->values;
              kernel_pixels=p;
              for (v=0; v < (ssize_t) kernel->width; v++)
              {
                for (u=0; u < (ssize_t) kernel->height; u++)
                {
                  pixel.opacity+=(*k)*kernel_pixels[u].opacity;
                  k++;
                }
                kernel_pixels+=image->columns+kernel->width;
              }
              SetOpacityPixelComponent(q,ClampOpacityPixelComponent(&pixel));
            }
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            {
              register const IndexPacket
                *restrict kernel_indexes;

              k=kernel->values;
              kernel_pixels=p;
              kernel_indexes=indexes;
              for (v=0; v < (ssize_t) kernel->width; v++)
              {
                for (u=0; u < (ssize_t) kernel->height; u++)
                {
                  alpha=(MagickRealType) (QuantumScale*(QuantumRange-
                    kernel_pixels[u].opacity));
                  pixel.index+=(*k)*alpha*kernel_indexes[u];
                  k++;
                }
                kernel_pixels+=image->columns+kernel->width;
                kernel_indexes+=image->columns+kernel->width;
              }
              filter_indexes[x]=ClampToQuantum(gamma*
                GetIndexPixelComponent(&pixel));
            }
        }
      indexes++;
      p++;
      q++;
    }
    sync=SyncCacheViewAuthenticPixels(filter_view,exception);
    if (sync == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_FilterImageChannel)
#endif
        proceed=SetImageProgress(image,FilterImageTag,progress++,image->rows);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  filter_image->type=image->type;
  filter_view=DestroyCacheView(filter_view);
  image_view=DestroyCacheView(image_view);
  if (status == MagickFalse)
    filter_image=DestroyImage(filter_image);
  return(filter_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     G a u s s i a n B l u r I m a g e                                       %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  GaussianBlurImage() blurs an image.  We convolve the image with a
%  Gaussian operator of the given radius and standard deviation (sigma).
%  For reasonable results, the radius should be larger than sigma.  Use a
%  radius of 0 and GaussianBlurImage() selects a suitable radius for you
%
%  The format of the GaussianBlurImage method is:
%
%      Image *GaussianBlurImage(const Image *image,onst double radius,
%        const double sigma,ExceptionInfo *exception)
%      Image *GaussianBlurImageChannel(const Image *image,
%        const ChannelType channel,const double radius,const double sigma,
%        ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: the channel type.
%
%    o radius: the radius of the Gaussian, in pixels, not counting the center
%      pixel.
%
%    o sigma: the standard deviation of the Gaussian, in pixels.
%
%    o exception: return any errors or warnings in this structure.
%
*/

MagickExport Image *GaussianBlurImage(const Image *image,const double radius,
  const double sigma,ExceptionInfo *exception)
{
  Image
    *blur_image;

  blur_image=GaussianBlurImageChannel(image,DefaultChannels,radius,sigma,
    exception);
  return(blur_image);
}

MagickExport Image *GaussianBlurImageChannel(const Image *image,
  const ChannelType channel,const double radius,const double sigma,
  ExceptionInfo *exception)
{
  double
    *kernel;

  Image
    *blur_image;

  register ssize_t
    i;

  size_t
    width;

  ssize_t
    j,
    u,
    v;

  assert(image != (const Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  width=GetOptimalKernelWidth2D(radius,sigma);
  kernel=(double *) AcquireQuantumMemory((size_t) width,width*sizeof(*kernel));
  if (kernel == (double *) NULL)
    ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
  j=(ssize_t) width/2;
  i=0;
  for (v=(-j); v <= j; v++)
  {
    for (u=(-j); u <= j; u++)
      kernel[i++]=(double) (exp(-((double) u*u+v*v)/(2.0*MagickSigma*
        MagickSigma))/(2.0*MagickPI*MagickSigma*MagickSigma));
  }
  blur_image=ConvolveImageChannel(image,channel,width,kernel,exception);
  kernel=(double *) RelinquishMagickMemory(kernel);
  return(blur_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     M o t i o n B l u r I m a g e                                           %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  MotionBlurImage() simulates motion blur.  We convolve the image with a
%  Gaussian operator of the given radius and standard deviation (sigma).
%  For reasonable results, radius should be larger than sigma.  Use a
%  radius of 0 and MotionBlurImage() selects a suitable radius for you.
%  Angle gives the angle of the blurring motion.
%
%  Andrew Protano contributed this effect.
%
%  The format of the MotionBlurImage method is:
%
%    Image *MotionBlurImage(const Image *image,const double radius,
%      const double sigma,const double angle,ExceptionInfo *exception)
%    Image *MotionBlurImageChannel(const Image *image,const ChannelType channel,
%      const double radius,const double sigma,const double angle,
%      ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: the channel type.
%
%    o radius: the radius of the Gaussian, in pixels, not counting the center
%    o radius: the radius of the Gaussian, in pixels, not counting
%      the center pixel.
%
%    o sigma: the standard deviation of the Gaussian, in pixels.
%
%    o angle: Apply the effect along this angle.
%
%    o exception: return any errors or warnings in this structure.
%
*/

static double *GetMotionBlurKernel(const size_t width,const double sigma)
{
  double
    *kernel,
    normalize;

  register ssize_t
    i;

  /*
   Generate a 1-D convolution kernel.
  */
  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"...");
  kernel=(double *) AcquireQuantumMemory((size_t) width,sizeof(*kernel));
  if (kernel == (double *) NULL)
    return(kernel);
  normalize=0.0;
  for (i=0; i < (ssize_t) width; i++)
  {
    kernel[i]=(double) (exp((-((double) i*i)/(double) (2.0*MagickSigma*
      MagickSigma)))/(MagickSQ2PI*MagickSigma));
    normalize+=kernel[i];
  }
  for (i=0; i < (ssize_t) width; i++)
    kernel[i]/=normalize;
  return(kernel);
}

MagickExport Image *MotionBlurImage(const Image *image,const double radius,
  const double sigma,const double angle,ExceptionInfo *exception)
{
  Image
    *motion_blur;

  motion_blur=MotionBlurImageChannel(image,DefaultChannels,radius,sigma,angle,
    exception);
  return(motion_blur);
}

MagickExport Image *MotionBlurImageChannel(const Image *image,
  const ChannelType channel,const double radius,const double sigma,
  const double angle,ExceptionInfo *exception)
{
  CacheView
    *blur_view,
    *image_view;

  double
    *kernel;

  Image
    *blur_image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  MagickPixelPacket
    bias;

  OffsetInfo
    *offset;

  PointInfo
    point;

  register ssize_t
    i;

  size_t
    width;

  ssize_t
    y;

  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  width=GetOptimalKernelWidth1D(radius,sigma);
  kernel=GetMotionBlurKernel(width,sigma);
  if (kernel == (double *) NULL)
    ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
  offset=(OffsetInfo *) AcquireQuantumMemory(width,sizeof(*offset));
  if (offset == (OffsetInfo *) NULL)
    {
      kernel=(double *) RelinquishMagickMemory(kernel);
      ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
    }
  blur_image=CloneImage(image,0,0,MagickTrue,exception);
  if (blur_image == (Image *) NULL)
    {
      kernel=(double *) RelinquishMagickMemory(kernel);
      offset=(OffsetInfo *) RelinquishMagickMemory(offset);
      return((Image *) NULL);
    }
  if (SetImageStorageClass(blur_image,DirectClass) == MagickFalse)
    {
      kernel=(double *) RelinquishMagickMemory(kernel);
      offset=(OffsetInfo *) RelinquishMagickMemory(offset);
      InheritException(exception,&blur_image->exception);
      blur_image=DestroyImage(blur_image);
      return((Image *) NULL);
    }
  point.x=(double) width*sin(DegreesToRadians(angle));
  point.y=(double) width*cos(DegreesToRadians(angle));
  for (i=0; i < (ssize_t) width; i++)
  {
    offset[i].x=(ssize_t) ceil((double) (i*point.y)/hypot(point.x,point.y)-0.5);
    offset[i].y=(ssize_t) ceil((double) (i*point.x)/hypot(point.x,point.y)-0.5);
  }
  /*
    Motion blur image.
  */
  status=MagickTrue;
  progress=0;
  GetMagickPixelPacket(image,&bias);
  image_view=AcquireCacheView(image);
  blur_view=AcquireCacheView(blur_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status) omp_throttle(1)
#endif
  for (y=0; y < (ssize_t) image->rows; y++)
  {
    register IndexPacket
      *restrict blur_indexes;

    register PixelPacket
      *restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    q=GetCacheViewAuthenticPixels(blur_view,0,y,blur_image->columns,1,
      exception);
    if (q == (PixelPacket *) NULL)
      {
        status=MagickFalse;
        continue;
      }
    blur_indexes=GetCacheViewAuthenticIndexQueue(blur_view);
    for (x=0; x < (ssize_t) image->columns; x++)
    {
      MagickPixelPacket
        qixel;

      PixelPacket
        pixel;

      register const IndexPacket
        *restrict indexes;

      register double
        *restrict k;

      register ssize_t
        i;

      k=kernel;
      qixel=bias;
      if (((channel & OpacityChannel) == 0) || (image->matte == MagickFalse))
        {
          for (i=0; i < (ssize_t) width; i++)
          {
            (void) GetOneCacheViewVirtualPixel(image_view,x+offset[i].x,y+
              offset[i].y,&pixel,exception);
            qixel.red+=(*k)*pixel.red;
            qixel.green+=(*k)*pixel.green;
            qixel.blue+=(*k)*pixel.blue;
            qixel.opacity+=(*k)*pixel.opacity;
            if (image->colorspace == CMYKColorspace)
              {
                indexes=GetCacheViewVirtualIndexQueue(image_view);
                qixel.index+=(*k)*(*indexes);
              }
            k++;
          }
          if ((channel & RedChannel) != 0)
            q->red=ClampToQuantum(qixel.red);
          if ((channel & GreenChannel) != 0)
            q->green=ClampToQuantum(qixel.green);
          if ((channel & BlueChannel) != 0)
            q->blue=ClampToQuantum(qixel.blue);
          if ((channel & OpacityChannel) != 0)
            q->opacity=ClampToQuantum(qixel.opacity);
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            blur_indexes[x]=(IndexPacket) ClampToQuantum(qixel.index);
        }
      else
        {
          MagickRealType
            alpha,
            gamma;

          alpha=0.0;
          gamma=0.0;
          for (i=0; i < (ssize_t) width; i++)
          {
            (void) GetOneCacheViewVirtualPixel(image_view,x+offset[i].x,y+
              offset[i].y,&pixel,exception);
            alpha=(MagickRealType) (QuantumScale*
              GetAlphaPixelComponent(&pixel));
            qixel.red+=(*k)*alpha*pixel.red;
            qixel.green+=(*k)*alpha*pixel.green;
            qixel.blue+=(*k)*alpha*pixel.blue;
            qixel.opacity+=(*k)*pixel.opacity;
            if (image->colorspace == CMYKColorspace)
              {
                indexes=GetCacheViewVirtualIndexQueue(image_view);
                qixel.index+=(*k)*alpha*(*indexes);
              }
            gamma+=(*k)*alpha;
            k++;
          }
          gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
          if ((channel & RedChannel) != 0)
            q->red=ClampToQuantum(gamma*qixel.red);
          if ((channel & GreenChannel) != 0)
            q->green=ClampToQuantum(gamma*qixel.green);
          if ((channel & BlueChannel) != 0)
            q->blue=ClampToQuantum(gamma*qixel.blue);
          if ((channel & OpacityChannel) != 0)
            q->opacity=ClampToQuantum(qixel.opacity);
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            blur_indexes[x]=(IndexPacket) ClampToQuantum(gamma*qixel.index);
        }
      q++;
    }
    if (SyncCacheViewAuthenticPixels(blur_view,exception) == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_MotionBlurImageChannel)
#endif
        proceed=SetImageProgress(image,BlurImageTag,progress++,image->rows);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  blur_view=DestroyCacheView(blur_view);
  image_view=DestroyCacheView(image_view);
  kernel=(double *) RelinquishMagickMemory(kernel);
  offset=(OffsetInfo *) RelinquishMagickMemory(offset);
  if (status == MagickFalse)
    blur_image=DestroyImage(blur_image);
  return(blur_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     P r e v i e w I m a g e                                                 %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  PreviewImage() tiles 9 thumbnails of the specified image with an image
%  processing operation applied with varying parameters.  This may be helpful
%  pin-pointing an appropriate parameter for a particular image processing
%  operation.
%
%  The format of the PreviewImages method is:
%
%      Image *PreviewImages(const Image *image,const PreviewType preview,
%        ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o preview: the image processing operation.
%
%    o exception: return any errors or warnings in this structure.
%
*/
MagickExport Image *PreviewImage(const Image *image,const PreviewType preview,
  ExceptionInfo *exception)
{
#define NumberTiles  9
#define PreviewImageTag  "Preview/Image"
#define DefaultPreviewGeometry  "204x204+10+10"

  char
    factor[MaxTextExtent],
    label[MaxTextExtent];

  double
    degrees,
    gamma,
    percentage,
    radius,
    sigma,
    threshold;

  Image
    *images,
    *montage_image,
    *preview_image,
    *thumbnail;

  ImageInfo
    *preview_info;

  MagickBooleanType
    proceed;

  MontageInfo
    *montage_info;

  QuantizeInfo
    quantize_info;

  RectangleInfo
    geometry;

  register ssize_t
    i,
    x;

  size_t
    colors;

  ssize_t
    y;

  /*
    Open output image file.
  */
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  colors=2;
  degrees=0.0;
  gamma=(-0.2f);
  preview_info=AcquireImageInfo();
  SetGeometry(image,&geometry);
  (void) ParseMetaGeometry(DefaultPreviewGeometry,&geometry.x,&geometry.y,
    &geometry.width,&geometry.height);
  images=NewImageList();
  percentage=12.5;
  GetQuantizeInfo(&quantize_info);
  radius=0.0;
  sigma=1.0;
  threshold=0.0;
  x=0;
  y=0;
  for (i=0; i < NumberTiles; i++)
  {
    thumbnail=ThumbnailImage(image,geometry.width,geometry.height,exception);
    if (thumbnail == (Image *) NULL)
      break;
    (void) SetImageProgressMonitor(thumbnail,(MagickProgressMonitor) NULL,
      (void *) NULL);
    (void) SetImageProperty(thumbnail,"label",DefaultTileLabel);
    if (i == (NumberTiles/2))
      {
        (void) QueryColorDatabase("#dfdfdf",&thumbnail->matte_color,exception);
        AppendImageToList(&images,thumbnail);
        continue;
      }
    switch (preview)
    {
      case RotatePreview:
      {
        degrees+=45.0;
        preview_image=RotateImage(thumbnail,degrees,exception);
        (void) FormatMagickString(label,MaxTextExtent,"rotate %g",degrees);
        break;
      }
      case ShearPreview:
      {
        degrees+=5.0;
        preview_image=ShearImage(thumbnail,degrees,degrees,exception);
        (void) FormatMagickString(label,MaxTextExtent,"shear %gx%g",
          degrees,2.0*degrees);
        break;
      }
      case RollPreview:
      {
        x=(ssize_t) ((i+1)*thumbnail->columns)/NumberTiles;
        y=(ssize_t) ((i+1)*thumbnail->rows)/NumberTiles;
        preview_image=RollImage(thumbnail,x,y,exception);
        (void) FormatMagickString(label,MaxTextExtent,"roll %+.20gx%+.20g",
          (double) x,(double) y);
        break;
      }
      case HuePreview:
      {
        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image == (Image *) NULL)
          break;
        (void) FormatMagickString(factor,MaxTextExtent,"100,100,%g",
          2.0*percentage);
        (void) ModulateImage(preview_image,factor);
        (void) FormatMagickString(label,MaxTextExtent,"modulate %s",factor);
        break;
      }
      case SaturationPreview:
      {
        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image == (Image *) NULL)
          break;
        (void) FormatMagickString(factor,MaxTextExtent,"100,%g",
          2.0*percentage);
        (void) ModulateImage(preview_image,factor);
        (void) FormatMagickString(label,MaxTextExtent,"modulate %s",factor);
        break;
      }
      case BrightnessPreview:
      {
        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image == (Image *) NULL)
          break;
        (void) FormatMagickString(factor,MaxTextExtent,"%g",2.0*percentage);
        (void) ModulateImage(preview_image,factor);
        (void) FormatMagickString(label,MaxTextExtent,"modulate %s",factor);
        break;
      }
      case GammaPreview:
      default:
      {
        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image == (Image *) NULL)
          break;
        gamma+=0.4f;
        (void) GammaImageChannel(preview_image,DefaultChannels,gamma);
        (void) FormatMagickString(label,MaxTextExtent,"gamma %g",gamma);
        break;
      }
      case SpiffPreview:
      {
        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image != (Image *) NULL)
          for (x=0; x < i; x++)
            (void) ContrastImage(preview_image,MagickTrue);
        (void) FormatMagickString(label,MaxTextExtent,"contrast (%.20g)",
          (double) i+1);
        break;
      }
      case DullPreview:
      {
        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image == (Image *) NULL)
          break;
        for (x=0; x < i; x++)
          (void) ContrastImage(preview_image,MagickFalse);
        (void) FormatMagickString(label,MaxTextExtent,"+contrast (%.20g)",
          (double) i+1);
        break;
      }
      case GrayscalePreview:
      {
        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image == (Image *) NULL)
          break;
        colors<<=1;
        quantize_info.number_colors=colors;
        quantize_info.colorspace=GRAYColorspace;
        (void) QuantizeImage(&quantize_info,preview_image);
        (void) FormatMagickString(label,MaxTextExtent,
          "-colorspace gray -colors %.20g",(double) colors);
        break;
      }
      case QuantizePreview:
      {
        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image == (Image *) NULL)
          break;
        colors<<=1;
        quantize_info.number_colors=colors;
        (void) QuantizeImage(&quantize_info,preview_image);
        (void) FormatMagickString(label,MaxTextExtent,"colors %.20g",(double)
          colors);
        break;
      }
      case DespecklePreview:
      {
        for (x=0; x < (i-1); x++)
        {
          preview_image=DespeckleImage(thumbnail,exception);
          if (preview_image == (Image *) NULL)
            break;
          thumbnail=DestroyImage(thumbnail);
          thumbnail=preview_image;
        }
        preview_image=DespeckleImage(thumbnail,exception);
        if (preview_image == (Image *) NULL)
          break;
        (void) FormatMagickString(label,MaxTextExtent,"despeckle (%.20g)",
          (double) i+1);
        break;
      }
      case ReduceNoisePreview:
      {
        preview_image=StatisticImage(thumbnail,NonpeakStatistic,(size_t) radius,
          (size_t) radius,exception);
        (void) FormatMagickString(label,MaxTextExtent,"noise %g",radius);
        break;
      }
      case AddNoisePreview:
      {
        switch ((int) i)
        {
          case 0:
          {
            (void) CopyMagickString(factor,"uniform",MaxTextExtent);
            break;
          }
          case 1:
          {
            (void) CopyMagickString(factor,"gaussian",MaxTextExtent);
            break;
          }
          case 2:
          {
            (void) CopyMagickString(factor,"multiplicative",MaxTextExtent);
            break;
          }
          case 3:
          {
            (void) CopyMagickString(factor,"impulse",MaxTextExtent);
            break;
          }
          case 4:
          {
            (void) CopyMagickString(factor,"laplacian",MaxTextExtent);
            break;
          }
          case 5:
          {
            (void) CopyMagickString(factor,"Poisson",MaxTextExtent);
            break;
          }
          default:
          {
            (void) CopyMagickString(thumbnail->magick,"NULL",MaxTextExtent);
            break;
          }
        }
        preview_image=StatisticImage(thumbnail,NonpeakStatistic,(size_t) i,
          (size_t) i,exception);
        (void) FormatMagickString(label,MaxTextExtent,"+noise %s",factor);
        break;
      }
      case SharpenPreview:
      {
        preview_image=SharpenImage(thumbnail,radius,sigma,exception);
        (void) FormatMagickString(label,MaxTextExtent,"sharpen %gx%g",
          radius,sigma);
        break;
      }
      case BlurPreview:
      {
        preview_image=BlurImage(thumbnail,radius,sigma,exception);
        (void) FormatMagickString(label,MaxTextExtent,"blur %gx%g",radius,
          sigma);
        break;
      }
      case ThresholdPreview:
      {
        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image == (Image *) NULL)
          break;
        (void) BilevelImage(thumbnail,
          (double) (percentage*((MagickRealType) QuantumRange+1.0))/100.0);
        (void) FormatMagickString(label,MaxTextExtent,"threshold %g",
          (double) (percentage*((MagickRealType) QuantumRange+1.0))/100.0);
        break;
      }
      case EdgeDetectPreview:
      {
        preview_image=EdgeImage(thumbnail,radius,exception);
        (void) FormatMagickString(label,MaxTextExtent,"edge %g",radius);
        break;
      }
      case SpreadPreview:
      {
        preview_image=SpreadImage(thumbnail,radius,exception);
        (void) FormatMagickString(label,MaxTextExtent,"spread %g",
          radius+0.5);
        break;
      }
      case SolarizePreview:
      {
        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image == (Image *) NULL)
          break;
        (void) SolarizeImage(preview_image,(double) QuantumRange*
          percentage/100.0);
        (void) FormatMagickString(label,MaxTextExtent,"solarize %g",
          (QuantumRange*percentage)/100.0);
        break;
      }
      case ShadePreview:
      {
        degrees+=10.0;
        preview_image=ShadeImage(thumbnail,MagickTrue,degrees,degrees,
          exception);
        (void) FormatMagickString(label,MaxTextExtent,"shade %gx%g",
          degrees,degrees);
        break;
      }
      case RaisePreview:
      {
        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image == (Image *) NULL)
          break;
        geometry.width=(size_t) (2*i+2);
        geometry.height=(size_t) (2*i+2);
        geometry.x=i/2;
        geometry.y=i/2;
        (void) RaiseImage(preview_image,&geometry,MagickTrue);
        (void) FormatMagickString(label,MaxTextExtent,
          "raise %.20gx%.20g%+.20g%+.20g",(double) geometry.width,(double)
          geometry.height,(double) geometry.x,(double) geometry.y);
        break;
      }
      case SegmentPreview:
      {
        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image == (Image *) NULL)
          break;
        threshold+=0.4f;
        (void) SegmentImage(preview_image,RGBColorspace,MagickFalse,threshold,
          threshold);
        (void) FormatMagickString(label,MaxTextExtent,"segment %gx%g",
          threshold,threshold);
        break;
      }
      case SwirlPreview:
      {
        preview_image=SwirlImage(thumbnail,degrees,exception);
        (void) FormatMagickString(label,MaxTextExtent,"swirl %g",degrees);
        degrees+=45.0;
        break;
      }
      case ImplodePreview:
      {
        degrees+=0.1f;
        preview_image=ImplodeImage(thumbnail,degrees,exception);
        (void) FormatMagickString(label,MaxTextExtent,"implode %g",degrees);
        break;
      }
      case WavePreview:
      {
        degrees+=5.0f;
        preview_image=WaveImage(thumbnail,0.5*degrees,2.0*degrees,exception);
        (void) FormatMagickString(label,MaxTextExtent,"wave %gx%g",
          0.5*degrees,2.0*degrees);
        break;
      }
      case OilPaintPreview:
      {
        preview_image=OilPaintImage(thumbnail,(double) radius,exception);
        (void) FormatMagickString(label,MaxTextExtent,"paint %g",radius);
        break;
      }
      case CharcoalDrawingPreview:
      {
        preview_image=CharcoalImage(thumbnail,(double) radius,(double) sigma,
          exception);
        (void) FormatMagickString(label,MaxTextExtent,"charcoal %gx%g",
          radius,sigma);
        break;
      }
      case JPEGPreview:
      {
        char
          filename[MaxTextExtent];

        int
          file;

        MagickBooleanType
          status;

        preview_image=CloneImage(thumbnail,0,0,MagickTrue,exception);
        if (preview_image == (Image *) NULL)
          break;
        preview_info->quality=(size_t) percentage;
        (void) FormatMagickString(factor,MaxTextExtent,"%.20g",(double)
          preview_info->quality);
        file=AcquireUniqueFileResource(filename);
        if (file != -1)
          file=close(file)-1;
        (void) FormatMagickString(preview_image->filename,MaxTextExtent,
          "jpeg:%s",filename);
        status=WriteImage(preview_info,preview_image);
        if (status != MagickFalse)
          {
            Image
              *quality_image;

            (void) CopyMagickString(preview_info->filename,
              preview_image->filename,MaxTextExtent);
            quality_image=ReadImage(preview_info,exception);
            if (quality_image != (Image *) NULL)
              {
                preview_image=DestroyImage(preview_image);
                preview_image=quality_image;
              }
          }
        (void) RelinquishUniqueFileResource(preview_image->filename);
        if ((GetBlobSize(preview_image)/1024) >= 1024)
          (void) FormatMagickString(label,MaxTextExtent,"quality %s\n%gmb ",
            factor,(double) ((MagickOffsetType) GetBlobSize(preview_image))/
            1024.0/1024.0);
        else
          if (GetBlobSize(preview_image) >= 1024)
            (void) FormatMagickString(label,MaxTextExtent,
              "quality %s\n%gkb ",factor,(double) ((MagickOffsetType)
              GetBlobSize(preview_image))/1024.0);
          else
            (void) FormatMagickString(label,MaxTextExtent,"quality %s\n%.20gb ",
              factor,(double) GetBlobSize(thumbnail));
        break;
      }
    }
    thumbnail=DestroyImage(thumbnail);
    percentage+=12.5;
    radius+=0.5;
    sigma+=0.25;
    if (preview_image == (Image *) NULL)
      break;
    (void) DeleteImageProperty(preview_image,"label");
    (void) SetImageProperty(preview_image,"label",label);
    AppendImageToList(&images,preview_image);
    proceed=SetImageProgress(image,PreviewImageTag,(MagickOffsetType) i,
      NumberTiles);
    if (proceed == MagickFalse)
      break;
  }
  if (images == (Image *) NULL)
    {
      preview_info=DestroyImageInfo(preview_info);
      return((Image *) NULL);
    }
  /*
    Create the montage.
  */
  montage_info=CloneMontageInfo(preview_info,(MontageInfo *) NULL);
  (void) CopyMagickString(montage_info->filename,image->filename,MaxTextExtent);
  montage_info->shadow=MagickTrue;
  (void) CloneString(&montage_info->tile,"3x3");
  (void) CloneString(&montage_info->geometry,DefaultPreviewGeometry);
  (void) CloneString(&montage_info->frame,DefaultTileFrame);
  montage_image=MontageImages(images,montage_info,exception);
  montage_info=DestroyMontageInfo(montage_info);
  images=DestroyImageList(images);
  if (montage_image == (Image *) NULL)
    ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
  if (montage_image->montage != (char *) NULL)
    {
      /*
        Free image directory.
      */
      montage_image->montage=(char *) RelinquishMagickMemory(
        montage_image->montage);
      if (image->directory != (char *) NULL)
        montage_image->directory=(char *) RelinquishMagickMemory(
          montage_image->directory);
    }
  preview_info=DestroyImageInfo(preview_info);
  return(montage_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     R a d i a l B l u r I m a g e                                           %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  RadialBlurImage() applies a radial blur to the image.
%
%  Andrew Protano contributed this effect.
%
%  The format of the RadialBlurImage method is:
%
%    Image *RadialBlurImage(const Image *image,const double angle,
%      ExceptionInfo *exception)
%    Image *RadialBlurImageChannel(const Image *image,const ChannelType channel,
%      const double angle,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: the channel type.
%
%    o angle: the angle of the radial blur.
%
%    o exception: return any errors or warnings in this structure.
%
*/

MagickExport Image *RadialBlurImage(const Image *image,const double angle,
  ExceptionInfo *exception)
{
  Image
    *blur_image;

  blur_image=RadialBlurImageChannel(image,DefaultChannels,angle,exception);
  return(blur_image);
}

MagickExport Image *RadialBlurImageChannel(const Image *image,
  const ChannelType channel,const double angle,ExceptionInfo *exception)
{
  CacheView
    *blur_view,
    *image_view;

  Image
    *blur_image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  MagickPixelPacket
    bias;

  MagickRealType
    blur_radius,
    *cos_theta,
    offset,
    *sin_theta,
    theta;

  PointInfo
    blur_center;

  register ssize_t
    i;

  size_t
    n;

  ssize_t
    y;

  /*
    Allocate blur image.
  */
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  blur_image=CloneImage(image,0,0,MagickTrue,exception);
  if (blur_image == (Image *) NULL)
    return((Image *) NULL);
  if (SetImageStorageClass(blur_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&blur_image->exception);
      blur_image=DestroyImage(blur_image);
      return((Image *) NULL);
    }
  blur_center.x=(double) image->columns/2.0;
  blur_center.y=(double) image->rows/2.0;
  blur_radius=hypot(blur_center.x,blur_center.y);
  n=(size_t) fabs(4.0*DegreesToRadians(angle)*sqrt((double) blur_radius)+2UL);
  theta=DegreesToRadians(angle)/(MagickRealType) (n-1);
  cos_theta=(MagickRealType *) AcquireQuantumMemory((size_t) n,
    sizeof(*cos_theta));
  sin_theta=(MagickRealType *) AcquireQuantumMemory((size_t) n,
    sizeof(*sin_theta));
  if ((cos_theta == (MagickRealType *) NULL) ||
      (sin_theta == (MagickRealType *) NULL))
    {
      blur_image=DestroyImage(blur_image);
      ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
    }
  offset=theta*(MagickRealType) (n-1)/2.0;
  for (i=0; i < (ssize_t) n; i++)
  {
    cos_theta[i]=cos((double) (theta*i-offset));
    sin_theta[i]=sin((double) (theta*i-offset));
  }
  /*
    Radial blur image.
  */
  status=MagickTrue;
  progress=0;
  GetMagickPixelPacket(image,&bias);
  image_view=AcquireCacheView(image);
  blur_view=AcquireCacheView(blur_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
  for (y=0; y < (ssize_t) blur_image->rows; y++)
  {
    register const IndexPacket
      *restrict indexes;

    register IndexPacket
      *restrict blur_indexes;

    register PixelPacket
      *restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    q=GetCacheViewAuthenticPixels(blur_view,0,y,blur_image->columns,1,
      exception);
    if (q == (PixelPacket *) NULL)
      {
        status=MagickFalse;
        continue;
      }
    blur_indexes=GetCacheViewAuthenticIndexQueue(blur_view);
    for (x=0; x < (ssize_t) blur_image->columns; x++)
    {
      MagickPixelPacket
        qixel;

      MagickRealType
        normalize,
        radius;

      PixelPacket
        pixel;

      PointInfo
        center;

      register ssize_t
        i;

      size_t
        step;

      center.x=(double) x-blur_center.x;
      center.y=(double) y-blur_center.y;
      radius=hypot((double) center.x,center.y);
      if (radius == 0)
        step=1;
      else
        {
          step=(size_t) (blur_radius/radius);
          if (step == 0)
            step=1;
          else
            if (step >= n)
              step=n-1;
        }
      normalize=0.0;
      qixel=bias;
      if (((channel & OpacityChannel) == 0) || (image->matte == MagickFalse))
        {
          for (i=0; i < (ssize_t) n; i+=(ssize_t) step)
          {
            (void) GetOneCacheViewVirtualPixel(image_view,(ssize_t)
              (blur_center.x+center.x*cos_theta[i]-center.y*sin_theta[i]+0.5),
              (ssize_t) (blur_center.y+center.x*sin_theta[i]+center.y*
              cos_theta[i]+0.5),&pixel,exception);
            qixel.red+=pixel.red;
            qixel.green+=pixel.green;
            qixel.blue+=pixel.blue;
            qixel.opacity+=pixel.opacity;
            if (image->colorspace == CMYKColorspace)
              {
                indexes=GetCacheViewVirtualIndexQueue(image_view);
                qixel.index+=(*indexes);
              }
            normalize+=1.0;
          }
          normalize=1.0/(fabs((double) normalize) <= MagickEpsilon ? 1.0 :
            normalize);
          if ((channel & RedChannel) != 0)
            q->red=ClampToQuantum(normalize*qixel.red);
          if ((channel & GreenChannel) != 0)
            q->green=ClampToQuantum(normalize*qixel.green);
          if ((channel & BlueChannel) != 0)
            q->blue=ClampToQuantum(normalize*qixel.blue);
          if ((channel & OpacityChannel) != 0)
            q->opacity=ClampToQuantum(normalize*qixel.opacity);
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            blur_indexes[x]=(IndexPacket) ClampToQuantum(normalize*qixel.index);
        }
      else
        {
          MagickRealType
            alpha,
            gamma;

          alpha=1.0;
          gamma=0.0;
          for (i=0; i < (ssize_t) n; i+=(ssize_t) step)
          {
            (void) GetOneCacheViewVirtualPixel(image_view,(ssize_t)
              (blur_center.x+center.x*cos_theta[i]-center.y*sin_theta[i]+0.5),
              (ssize_t) (blur_center.y+center.x*sin_theta[i]+center.y*
              cos_theta[i]+0.5),&pixel,exception);
            alpha=(MagickRealType) (QuantumScale*
              GetAlphaPixelComponent(&pixel));
            qixel.red+=alpha*pixel.red;
            qixel.green+=alpha*pixel.green;
            qixel.blue+=alpha*pixel.blue;
            qixel.opacity+=pixel.opacity;
            if (image->colorspace == CMYKColorspace)
              {
                indexes=GetCacheViewVirtualIndexQueue(image_view);
                qixel.index+=alpha*(*indexes);
              }
            gamma+=alpha;
            normalize+=1.0;
          }
          gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
          normalize=1.0/(fabs((double) normalize) <= MagickEpsilon ? 1.0 :
            normalize);
          if ((channel & RedChannel) != 0)
            q->red=ClampToQuantum(gamma*qixel.red);
          if ((channel & GreenChannel) != 0)
            q->green=ClampToQuantum(gamma*qixel.green);
          if ((channel & BlueChannel) != 0)
            q->blue=ClampToQuantum(gamma*qixel.blue);
          if ((channel & OpacityChannel) != 0)
            q->opacity=ClampToQuantum(normalize*qixel.opacity);
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            blur_indexes[x]=(IndexPacket) ClampToQuantum(gamma*qixel.index);
        }
      q++;
    }
    if (SyncCacheViewAuthenticPixels(blur_view,exception) == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_RadialBlurImageChannel)
#endif
        proceed=SetImageProgress(image,BlurImageTag,progress++,image->rows);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  blur_view=DestroyCacheView(blur_view);
  image_view=DestroyCacheView(image_view);
  cos_theta=(MagickRealType *) RelinquishMagickMemory(cos_theta);
  sin_theta=(MagickRealType *) RelinquishMagickMemory(sin_theta);
  if (status == MagickFalse)
    blur_image=DestroyImage(blur_image);
  return(blur_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     S e l e c t i v e B l u r I m a g e                                     %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  SelectiveBlurImage() selectively blur pixels within a contrast threshold.
%  It is similar to the unsharpen mask that sharpens everything with contrast
%  above a certain threshold.
%
%  The format of the SelectiveBlurImage method is:
%
%      Image *SelectiveBlurImage(const Image *image,const double radius,
%        const double sigma,const double threshold,ExceptionInfo *exception)
%      Image *SelectiveBlurImageChannel(const Image *image,
%        const ChannelType channel,const double radius,const double sigma,
%        const double threshold,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: the channel type.
%
%    o radius: the radius of the Gaussian, in pixels, not counting the center
%      pixel.
%
%    o sigma: the standard deviation of the Gaussian, in pixels.
%
%    o threshold: only pixels within this contrast threshold are included
%      in the blur operation.
%
%    o exception: return any errors or warnings in this structure.
%
*/

static inline MagickBooleanType SelectiveContrast(const PixelPacket *p,
  const PixelPacket *q,const double threshold)
{
  if (fabs(PixelIntensity(p)-PixelIntensity(q)) < threshold)
    return(MagickTrue);
  return(MagickFalse);
}

MagickExport Image *SelectiveBlurImage(const Image *image,const double radius,
  const double sigma,const double threshold,ExceptionInfo *exception)
{
  Image
    *blur_image;

  blur_image=SelectiveBlurImageChannel(image,DefaultChannels,radius,sigma,
    threshold,exception);
  return(blur_image);
}

MagickExport Image *SelectiveBlurImageChannel(const Image *image,
  const ChannelType channel,const double radius,const double sigma,
  const double threshold,ExceptionInfo *exception)
{
#define SelectiveBlurImageTag  "SelectiveBlur/Image"

  CacheView
    *blur_view,
    *image_view;

  double
    *kernel;

  Image
    *blur_image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  MagickPixelPacket
    bias;

  register ssize_t
    i;

  size_t
    width;

  ssize_t
    j,
    u,
    v,
    y;

  /*
    Initialize blur image attributes.
  */
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  width=GetOptimalKernelWidth1D(radius,sigma);
  kernel=(double *) AcquireQuantumMemory((size_t) width,width*sizeof(*kernel));
  if (kernel == (double *) NULL)
    ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
  j=(ssize_t) width/2;
  i=0;
  for (v=(-j); v <= j; v++)
  {
    for (u=(-j); u <= j; u++)
      kernel[i++]=(double) (exp(-((double) u*u+v*v)/(2.0*MagickSigma*
        MagickSigma))/(2.0*MagickPI*MagickSigma*MagickSigma));
  }
  if (image->debug != MagickFalse)
    {
      char
        format[MaxTextExtent],
        *message;

      register const double
        *k;

      ssize_t
        u,
        v;

      (void) LogMagickEvent(TransformEvent,GetMagickModule(),
        "  SelectiveBlurImage with %.20gx%.20g kernel:",(double) width,(double)
        width);
      message=AcquireString("");
      k=kernel;
      for (v=0; v < (ssize_t) width; v++)
      {
        *message='\0';
        (void) FormatMagickString(format,MaxTextExtent,"%.20g: ",(double) v);
        (void) ConcatenateString(&message,format);
        for (u=0; u < (ssize_t) width; u++)
        {
          (void) FormatMagickString(format,MaxTextExtent,"%+f ",*k++);
          (void) ConcatenateString(&message,format);
        }
        (void) LogMagickEvent(TransformEvent,GetMagickModule(),"%s",message);
      }
      message=DestroyString(message);
    }
  blur_image=CloneImage(image,0,0,MagickTrue,exception);
  if (blur_image == (Image *) NULL)
    return((Image *) NULL);
  if (SetImageStorageClass(blur_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&blur_image->exception);
      blur_image=DestroyImage(blur_image);
      return((Image *) NULL);
    }
  /*
    Threshold blur image.
  */
  status=MagickTrue;
  progress=0;
  GetMagickPixelPacket(image,&bias);
  SetMagickPixelPacketBias(image,&bias);
  image_view=AcquireCacheView(image);
  blur_view=AcquireCacheView(blur_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
  for (y=0; y < (ssize_t) image->rows; y++)
  {
    MagickBooleanType
      sync;

    MagickRealType
      gamma;

    register const IndexPacket
      *restrict indexes;

    register const PixelPacket
      *restrict p;

    register IndexPacket
      *restrict blur_indexes;

    register PixelPacket
      *restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    p=GetCacheViewVirtualPixels(image_view,-((ssize_t) width/2L),y-(ssize_t)
      (width/2L),image->columns+width,width,exception);
    q=GetCacheViewAuthenticPixels(blur_view,0,y,blur_image->columns,1,
      exception);
    if ((p == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
      {
        status=MagickFalse;
        continue;
      }
    indexes=GetCacheViewVirtualIndexQueue(image_view);
    blur_indexes=GetCacheViewAuthenticIndexQueue(blur_view);
    for (x=0; x < (ssize_t) image->columns; x++)
    {
      MagickPixelPacket
        pixel;

      register const double
        *restrict k;

      register ssize_t
        u;

      ssize_t
        j,
        v;

      pixel=bias;
      k=kernel;
      gamma=0.0;
      j=0;
      if (((channel & OpacityChannel) == 0) || (image->matte == MagickFalse))
        {
          for (v=0; v < (ssize_t) width; v++)
          {
            for (u=0; u < (ssize_t) width; u++)
            {
              if (SelectiveContrast(p+u+j,q,threshold) != MagickFalse)
                {
                  pixel.red+=(*k)*(p+u+j)->red;
                  pixel.green+=(*k)*(p+u+j)->green;
                  pixel.blue+=(*k)*(p+u+j)->blue;
                  gamma+=(*k);
                  k++;
                }
            }
            j+=(ssize_t) (image->columns+width);
          }
          if (gamma != 0.0)
            {
              gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
              if ((channel & RedChannel) != 0)
                q->red=ClampToQuantum(gamma*GetRedPixelComponent(&pixel));
              if ((channel & GreenChannel) != 0)
                q->green=ClampToQuantum(gamma*GetGreenPixelComponent(&pixel));
              if ((channel & BlueChannel) != 0)
                q->blue=ClampToQuantum(gamma*GetBluePixelComponent(&pixel));
            }
          if ((channel & OpacityChannel) != 0)
            {
              gamma=0.0;
              j=0;
              for (v=0; v < (ssize_t) width; v++)
              {
                for (u=0; u < (ssize_t) width; u++)
                {
                  if (SelectiveContrast(p+u+j,q,threshold) != MagickFalse)
                    {
                      pixel.opacity+=(*k)*(p+u+j)->opacity;
                      gamma+=(*k);
                      k++;
                    }
                }
                j+=(ssize_t) (image->columns+width);
              }
              if (gamma != 0.0)
                {
                  gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 :
                    gamma);
                  SetOpacityPixelComponent(q,ClampToQuantum(gamma*
                    GetOpacityPixelComponent(&pixel)));
                }
            }
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            {
              gamma=0.0;
              j=0;
              for (v=0; v < (ssize_t) width; v++)
              {
                for (u=0; u < (ssize_t) width; u++)
                {
                  if (SelectiveContrast(p+u+j,q,threshold) != MagickFalse)
                    {
                      pixel.index+=(*k)*indexes[x+u+j];
                      gamma+=(*k);
                      k++;
                    }
                }
                j+=(ssize_t) (image->columns+width);
              }
              if (gamma != 0.0)
                {
                  gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 :
                    gamma);
                  blur_indexes[x]=ClampToQuantum(gamma*
                    GetIndexPixelComponent(&pixel));
                }
            }
        }
      else
        {
          MagickRealType
            alpha;

          for (v=0; v < (ssize_t) width; v++)
          {
            for (u=0; u < (ssize_t) width; u++)
            {
              if (SelectiveContrast(p+u+j,q,threshold) != MagickFalse)
                {
                  alpha=(MagickRealType) (QuantumScale*
                    GetAlphaPixelComponent(p+u+j));
                  pixel.red+=(*k)*alpha*(p+u+j)->red;
                  pixel.green+=(*k)*alpha*(p+u+j)->green;
                  pixel.blue+=(*k)*alpha*(p+u+j)->blue;
                  pixel.opacity+=(*k)*(p+u+j)->opacity;
                  gamma+=(*k)*alpha;
                  k++;
                }
            }
            j+=(ssize_t) (image->columns+width);
          }
          if (gamma != 0.0)
            {
              gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
              if ((channel & RedChannel) != 0)
                q->red=ClampToQuantum(gamma*GetRedPixelComponent(&pixel));
              if ((channel & GreenChannel) != 0)
                q->green=ClampToQuantum(gamma*GetGreenPixelComponent(&pixel));
              if ((channel & BlueChannel) != 0)
                q->blue=ClampToQuantum(gamma*GetBluePixelComponent(&pixel));
            }
          if ((channel & OpacityChannel) != 0)
            {
              gamma=0.0;
              j=0;
              for (v=0; v < (ssize_t) width; v++)
              {
                for (u=0; u < (ssize_t) width; u++)
                {
                  if (SelectiveContrast(p+u+j,q,threshold) != MagickFalse)
                    {
                      pixel.opacity+=(*k)*(p+u+j)->opacity;
                      gamma+=(*k);
                      k++;
                    }
                }
                j+=(ssize_t) (image->columns+width);
              }
              if (gamma != 0.0)
                {
                  gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 :
                    gamma);
                  SetOpacityPixelComponent(q,
                    ClampOpacityPixelComponent(&pixel));
                }
            }
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            {
              gamma=0.0;
              j=0;
              for (v=0; v < (ssize_t) width; v++)
              {
                for (u=0; u < (ssize_t) width; u++)
                {
                  if (SelectiveContrast(p+u+j,q,threshold) != MagickFalse)
                    {
                      alpha=(MagickRealType) (QuantumScale*
                        GetAlphaPixelComponent(p+u+j));
                      pixel.index+=(*k)*alpha*indexes[x+u+j];
                      gamma+=(*k);
                      k++;
                    }
                }
                j+=(ssize_t) (image->columns+width);
              }
              if (gamma != 0.0)
                {
                  gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 :
                    gamma);
                  blur_indexes[x]=ClampToQuantum(gamma*
                    GetIndexPixelComponent(&pixel));
                }
            }
        }
      p++;
      q++;
    }
    sync=SyncCacheViewAuthenticPixels(blur_view,exception);
    if (sync == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_SelectiveBlurImageChannel)
#endif
        proceed=SetImageProgress(image,SelectiveBlurImageTag,progress++,
          image->rows);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  blur_image->type=image->type;
  blur_view=DestroyCacheView(blur_view);
  image_view=DestroyCacheView(image_view);
  kernel=(double *) RelinquishMagickMemory(kernel);
  if (status == MagickFalse)
    blur_image=DestroyImage(blur_image);
  return(blur_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     S h a d e I m a g e                                                     %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  ShadeImage() shines a distant light on an image to create a
%  three-dimensional effect. You control the positioning of the light with
%  azimuth and elevation; azimuth is measured in degrees off the x axis
%  and elevation is measured in pixels above the Z axis.
%
%  The format of the ShadeImage method is:
%
%      Image *ShadeImage(const Image *image,const MagickBooleanType gray,
%        const double azimuth,const double elevation,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o gray: A value other than zero shades the intensity of each pixel.
%
%    o azimuth, elevation:  Define the light source direction.
%
%    o exception: return any errors or warnings in this structure.
%
*/
MagickExport Image *ShadeImage(const Image *image,const MagickBooleanType gray,
  const double azimuth,const double elevation,ExceptionInfo *exception)
{
#define ShadeImageTag  "Shade/Image"

  CacheView
    *image_view,
    *shade_view;

  Image
    *shade_image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  PrimaryInfo
    light;

  ssize_t
    y;

  /*
    Initialize shaded image attributes.
  */
  assert(image != (const Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  shade_image=CloneImage(image,image->columns,image->rows,MagickTrue,exception);
  if (shade_image == (Image *) NULL)
    return((Image *) NULL);
  if (SetImageStorageClass(shade_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&shade_image->exception);
      shade_image=DestroyImage(shade_image);
      return((Image *) NULL);
    }
  /*
    Compute the light vector.
  */
  light.x=(double) QuantumRange*cos(DegreesToRadians(azimuth))*
    cos(DegreesToRadians(elevation));
  light.y=(double) QuantumRange*sin(DegreesToRadians(azimuth))*
    cos(DegreesToRadians(elevation));
  light.z=(double) QuantumRange*sin(DegreesToRadians(elevation));
  /*
    Shade image.
  */
  status=MagickTrue;
  progress=0;
  image_view=AcquireCacheView(image);
  shade_view=AcquireCacheView(shade_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
  for (y=0; y < (ssize_t) image->rows; y++)
  {
    MagickRealType
      distance,
      normal_distance,
      shade;

    PrimaryInfo
      normal;

    register const PixelPacket
      *restrict p,
      *restrict s0,
      *restrict s1,
      *restrict s2;

    register PixelPacket
      *restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    p=GetCacheViewVirtualPixels(image_view,-1,y-1,image->columns+2,3,exception);
    q=QueueCacheViewAuthenticPixels(shade_view,0,y,shade_image->columns,1,
      exception);
    if ((p == (PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
      {
        status=MagickFalse;
        continue;
      }
    /*
      Shade this row of pixels.
    */
    normal.z=2.0*(double) QuantumRange;  /* constant Z of surface normal */
    s0=p+1;
    s1=s0+image->columns+2;
    s2=s1+image->columns+2;
    for (x=0; x < (ssize_t) image->columns; x++)
    {
      /*
        Determine the surface normal and compute shading.
      */
      normal.x=(double) (PixelIntensity(s0-1)+PixelIntensity(s1-1)+
        PixelIntensity(s2-1)-PixelIntensity(s0+1)-PixelIntensity(s1+1)-
        PixelIntensity(s2+1));
      normal.y=(double) (PixelIntensity(s2-1)+PixelIntensity(s2)+
        PixelIntensity(s2+1)-PixelIntensity(s0-1)-PixelIntensity(s0)-
        PixelIntensity(s0+1));
      if ((normal.x == 0.0) && (normal.y == 0.0))
        shade=light.z;
      else
        {
          shade=0.0;
          distance=normal.x*light.x+normal.y*light.y+normal.z*light.z;
          if (distance > MagickEpsilon)
            {
              normal_distance=
                normal.x*normal.x+normal.y*normal.y+normal.z*normal.z;
              if (normal_distance > (MagickEpsilon*MagickEpsilon))
                shade=distance/sqrt((double) normal_distance);
            }
        }
      if (gray != MagickFalse)
        {
          q->red=(Quantum) shade;
          q->green=(Quantum) shade;
          q->blue=(Quantum) shade;
        }
      else
        {
          q->red=ClampToQuantum(QuantumScale*shade*s1->red);
          q->green=ClampToQuantum(QuantumScale*shade*s1->green);
          q->blue=ClampToQuantum(QuantumScale*shade*s1->blue);
        }
      q->opacity=s1->opacity;
      s0++;
      s1++;
      s2++;
      q++;
    }
    if (SyncCacheViewAuthenticPixels(shade_view,exception) == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_ShadeImage)
#endif
        proceed=SetImageProgress(image,ShadeImageTag,progress++,image->rows);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  shade_view=DestroyCacheView(shade_view);
  image_view=DestroyCacheView(image_view);
  if (status == MagickFalse)
    shade_image=DestroyImage(shade_image);
  return(shade_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     S h a r p e n I m a g e                                                 %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  SharpenImage() sharpens the image.  We convolve the image with a Gaussian
%  operator of the given radius and standard deviation (sigma).  For
%  reasonable results, radius should be larger than sigma.  Use a radius of 0
%  and SharpenImage() selects a suitable radius for you.
%
%  Using a separable kernel would be faster, but the negative weights cancel
%  out on the corners of the kernel producing often undesirable ringing in the
%  filtered result; this can be avoided by using a 2D gaussian shaped image
%  sharpening kernel instead.
%
%  The format of the SharpenImage method is:
%
%    Image *SharpenImage(const Image *image,const double radius,
%      const double sigma,ExceptionInfo *exception)
%    Image *SharpenImageChannel(const Image *image,const ChannelType channel,
%      const double radius,const double sigma,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: the channel type.
%
%    o radius: the radius of the Gaussian, in pixels, not counting the center
%      pixel.
%
%    o sigma: the standard deviation of the Laplacian, in pixels.
%
%    o exception: return any errors or warnings in this structure.
%
*/

MagickExport Image *SharpenImage(const Image *image,const double radius,
  const double sigma,ExceptionInfo *exception)
{
  Image
    *sharp_image;

  sharp_image=SharpenImageChannel(image,DefaultChannels,radius,sigma,exception);
  return(sharp_image);
}

MagickExport Image *SharpenImageChannel(const Image *image,
  const ChannelType channel,const double radius,const double sigma,
  ExceptionInfo *exception)
{
  double
    *kernel,
    normalize;

  Image
    *sharp_image;

  register ssize_t
    i;

  size_t
    width;

  ssize_t
    j,
    u,
    v;

  assert(image != (const Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  width=GetOptimalKernelWidth2D(radius,sigma);
  kernel=(double *) AcquireQuantumMemory((size_t) width*width,sizeof(*kernel));
  if (kernel == (double *) NULL)
    ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
  normalize=0.0;
  j=(ssize_t) width/2;
  i=0;
  for (v=(-j); v <= j; v++)
  {
    for (u=(-j); u <= j; u++)
    {
      kernel[i]=(double) (-exp(-((double) u*u+v*v)/(2.0*MagickSigma*
        MagickSigma))/(2.0*MagickPI*MagickSigma*MagickSigma));
      normalize+=kernel[i];
      i++;
    }
  }
  kernel[i/2]=(double) ((-2.0)*normalize);
  sharp_image=ConvolveImageChannel(image,channel,width,kernel,exception);
  kernel=(double *) RelinquishMagickMemory(kernel);
  return(sharp_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     S p r e a d I m a g e                                                   %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  SpreadImage() is a special effects method that randomly displaces each
%  pixel in a block defined by the radius parameter.
%
%  The format of the SpreadImage method is:
%
%      Image *SpreadImage(const Image *image,const double radius,
%        ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o radius:  Choose a random pixel in a neighborhood of this extent.
%
%    o exception: return any errors or warnings in this structure.
%
*/
MagickExport Image *SpreadImage(const Image *image,const double radius,
  ExceptionInfo *exception)
{
#define SpreadImageTag  "Spread/Image"

  CacheView
    *image_view,
    *spread_view;

  Image
    *spread_image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  MagickPixelPacket
    bias;

  RandomInfo
    **restrict random_info;

  size_t
    width;

  ssize_t
    y;

  /*
    Initialize spread image attributes.
  */
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  spread_image=CloneImage(image,image->columns,image->rows,MagickTrue,
    exception);
  if (spread_image == (Image *) NULL)
    return((Image *) NULL);
  if (SetImageStorageClass(spread_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&spread_image->exception);
      spread_image=DestroyImage(spread_image);
      return((Image *) NULL);
    }
  /*
    Spread image.
  */
  status=MagickTrue;
  progress=0;
  GetMagickPixelPacket(spread_image,&bias);
  width=GetOptimalKernelWidth1D(radius,0.5);
  random_info=AcquireRandomInfoThreadSet();
  image_view=AcquireCacheView(image);
  spread_view=AcquireCacheView(spread_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status) omp_throttle(1)
#endif
  for (y=0; y < (ssize_t) spread_image->rows; y++)
  {
    const int
      id = GetOpenMPThreadId();

    MagickPixelPacket
      pixel;

    register IndexPacket
      *restrict indexes;

    register PixelPacket
      *restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    q=QueueCacheViewAuthenticPixels(spread_view,0,y,spread_image->columns,1,
      exception);
    if (q == (PixelPacket *) NULL)
      {
        status=MagickFalse;
        continue;
      }
    indexes=GetCacheViewAuthenticIndexQueue(spread_view);
    pixel=bias;
    for (x=0; x < (ssize_t) spread_image->columns; x++)
    {
      (void) InterpolateMagickPixelPacket(image,image_view,
        UndefinedInterpolatePixel,(double) x+width*(GetPseudoRandomValue(
        random_info[id])-0.5),(double) y+width*(GetPseudoRandomValue(
        random_info[id])-0.5),&pixel,exception);
      SetPixelPacket(spread_image,&pixel,q,indexes+x);
      q++;
    }
    if (SyncCacheViewAuthenticPixels(spread_view,exception) == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_SpreadImage)
#endif
        proceed=SetImageProgress(image,SpreadImageTag,progress++,image->rows);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  spread_view=DestroyCacheView(spread_view);
  image_view=DestroyCacheView(image_view);
  random_info=DestroyRandomInfoThreadSet(random_info);
  return(spread_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     S t a t i s t i c I m a g e                                             %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  StatisticImage() makes each pixel the min / max / median / mode / etc. of
%  the neighborhood of the specified width and height.
%
%  The format of the StatisticImage method is:
%
%      Image *StatisticImage(const Image *image,const StatisticType type,
%        const size_t width,const size_t height,ExceptionInfo *exception)
%      Image *StatisticImageChannel(const Image *image,
%        const ChannelType channel,const StatisticType type,
%        const size_t width,const size_t height,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: the image channel.
%
%    o type: the statistic type (median, mode, etc.).
%
%    o width: the width of the pixel neighborhood.
%
%    o height: the height of the pixel neighborhood.
%
%    o exception: return any errors or warnings in this structure.
%
*/

#define ListChannels  5

typedef struct _ListNode
{
  size_t
    next[9],
    count,
    signature;
} ListNode;

typedef struct _SkipList
{
  ssize_t
    level;

  ListNode
    *nodes;
} SkipList;

typedef struct _PixelList
{
  size_t
    length,
    seed,
    signature;

  SkipList
    lists[ListChannels];
} PixelList;

static PixelList *DestroyPixelList(PixelList *pixel_list)
{
  register ssize_t
    i;

  if (pixel_list == (PixelList *) NULL)
    return((PixelList *) NULL);
  for (i=0; i < ListChannels; i++)
    if (pixel_list->lists[i].nodes != (ListNode *) NULL)
      pixel_list->lists[i].nodes=(ListNode *) RelinquishMagickMemory(
        pixel_list->lists[i].nodes);
  pixel_list=(PixelList *) RelinquishMagickMemory(pixel_list);
  return(pixel_list);
}

static PixelList **DestroyPixelListThreadSet(PixelList **pixel_list)
{
  register ssize_t
    i;

  assert(pixel_list != (PixelList **) NULL);
  for (i=0; i < (ssize_t) GetOpenMPMaximumThreads(); i++)
    if (pixel_list[i] != (PixelList *) NULL)
      pixel_list[i]=DestroyPixelList(pixel_list[i]);
  pixel_list=(PixelList **) RelinquishMagickMemory(pixel_list);
  return(pixel_list);
}

static PixelList *AcquirePixelList(const size_t width,const size_t height)
{
  PixelList
    *pixel_list;

  register ssize_t
    i;

  pixel_list=(PixelList *) AcquireMagickMemory(sizeof(*pixel_list));
  if (pixel_list == (PixelList *) NULL)
    return(pixel_list);
  (void) ResetMagickMemory((void *) pixel_list,0,sizeof(*pixel_list));
  pixel_list->length=width*height;
  for (i=0; i < ListChannels; i++)
  {
    pixel_list->lists[i].nodes=(ListNode *) AcquireQuantumMemory(65537UL,
      sizeof(*pixel_list->lists[i].nodes));
    if (pixel_list->lists[i].nodes == (ListNode *) NULL)
      return(DestroyPixelList(pixel_list));
    (void) ResetMagickMemory(pixel_list->lists[i].nodes,0,65537UL*
      sizeof(*pixel_list->lists[i].nodes));
  }
  pixel_list->signature=MagickSignature;
  return(pixel_list);
}

static PixelList **AcquirePixelListThreadSet(const size_t width,
  const size_t height)
{
  PixelList
    **pixel_list;

  register ssize_t
    i;

  size_t
    number_threads;

  number_threads=GetOpenMPMaximumThreads();
  pixel_list=(PixelList **) AcquireQuantumMemory(number_threads,
    sizeof(*pixel_list));
  if (pixel_list == (PixelList **) NULL)
    return((PixelList **) NULL);
  (void) ResetMagickMemory(pixel_list,0,number_threads*sizeof(*pixel_list));
  for (i=0; i < (ssize_t) number_threads; i++)
  {
    pixel_list[i]=AcquirePixelList(width,height);
    if (pixel_list[i] == (PixelList *) NULL)
      return(DestroyPixelListThreadSet(pixel_list));
  }
  return(pixel_list);
}

static void AddNodePixelList(PixelList *pixel_list,const ssize_t channel,
  const size_t color)
{
  register SkipList
    *list;

  register ssize_t
    level;

  size_t
    search,
    update[9];

  /*
    Initialize the node.
  */
  list=pixel_list->lists+channel;
  list->nodes[color].signature=pixel_list->signature;
  list->nodes[color].count=1;
  /*
    Determine where it belongs in the list.
  */
  search=65536UL;
  for (level=list->level; level >= 0; level--)
  {
    while (list->nodes[search].next[level] < color)
      search=list->nodes[search].next[level];
    update[level]=search;
  }
  /*
    Generate a pseudo-random level for this node.
  */
  for (level=0; ; level++)
  {
    pixel_list->seed=(pixel_list->seed*42893621L)+1L;
    if ((pixel_list->seed & 0x300) != 0x300)
      break;
  }
  if (level > 8)
    level=8;
  if (level > (list->level+2))
    level=list->level+2;
  /*
    If we're raising the list's level, link back to the root node.
  */
  while (level > list->level)
  {
    list->level++;
    update[list->level]=65536UL;
  }
  /*
    Link the node into the skip-list.
  */
  do
  {
    list->nodes[color].next[level]=list->nodes[update[level]].next[level];
    list->nodes[update[level]].next[level]=color;
  } while (level-- > 0);
}

static MagickPixelPacket GetMaximumPixelList(PixelList *pixel_list)
{
  MagickPixelPacket
    pixel;

  register SkipList
    *list;

  register ssize_t
    channel;

  size_t
    color,
    maximum;

  ssize_t
    count;

  unsigned short
    channels[ListChannels];

  /*
    Find the maximum value for each of the color.
  */
  for (channel=0; channel < 5; channel++)
  {
    list=pixel_list->lists+channel;
    color=65536L;
    count=0;
    maximum=list->nodes[color].next[0];
    do
    {
      color=list->nodes[color].next[0];
      if (color > maximum)
        maximum=color;
      count+=list->nodes[color].count;
    } while (count < (ssize_t) pixel_list->length);
    channels[channel]=(unsigned short) maximum;
  }
  GetMagickPixelPacket((const Image *) NULL,&pixel);
  pixel.red=(MagickRealType) ScaleShortToQuantum(channels[0]);
  pixel.green=(MagickRealType) ScaleShortToQuantum(channels[1]);
  pixel.blue=(MagickRealType) ScaleShortToQuantum(channels[2]);
  pixel.opacity=(MagickRealType) ScaleShortToQuantum(channels[3]);
  pixel.index=(MagickRealType) ScaleShortToQuantum(channels[4]);
  return(pixel);
}

static MagickPixelPacket GetMeanPixelList(PixelList *pixel_list)
{
  MagickPixelPacket
    pixel;

  MagickRealType
    sum;

  register SkipList
    *list;

  register ssize_t
    channel;

  size_t
    color;

  ssize_t
    count;

  unsigned short
    channels[ListChannels];

  /*
    Find the mean value for each of the color.
  */
  for (channel=0; channel < 5; channel++)
  {
    list=pixel_list->lists+channel;
    color=65536L;
    count=0;
    sum=0.0;
    do
    {
      color=list->nodes[color].next[0];
      sum+=(MagickRealType) list->nodes[color].count*color;
      count+=list->nodes[color].count;
    } while (count < (ssize_t) pixel_list->length);
    sum/=pixel_list->length;
    channels[channel]=(unsigned short) sum;
  }
  GetMagickPixelPacket((const Image *) NULL,&pixel);
  pixel.red=(MagickRealType) ScaleShortToQuantum(channels[0]);
  pixel.green=(MagickRealType) ScaleShortToQuantum(channels[1]);
  pixel.blue=(MagickRealType) ScaleShortToQuantum(channels[2]);
  pixel.opacity=(MagickRealType) ScaleShortToQuantum(channels[3]);
  pixel.index=(MagickRealType) ScaleShortToQuantum(channels[4]);
  return(pixel);
}

static MagickPixelPacket GetMedianPixelList(PixelList *pixel_list)
{
  MagickPixelPacket
    pixel;

  register SkipList
    *list;

  register ssize_t
    channel;

  size_t
    color;

  ssize_t
    count;

  unsigned short
    channels[ListChannels];

  /*
    Find the median value for each of the color.
  */
  for (channel=0; channel < 5; channel++)
  {
    list=pixel_list->lists+channel;
    color=65536L;
    count=0;
    do
    {
      color=list->nodes[color].next[0];
      count+=list->nodes[color].count;
    } while (count <= (ssize_t) (pixel_list->length >> 1));
    channels[channel]=(unsigned short) color;
  }
  GetMagickPixelPacket((const Image *) NULL,&pixel);
  pixel.red=(MagickRealType) ScaleShortToQuantum(channels[0]);
  pixel.green=(MagickRealType) ScaleShortToQuantum(channels[1]);
  pixel.blue=(MagickRealType) ScaleShortToQuantum(channels[2]);
  pixel.opacity=(MagickRealType) ScaleShortToQuantum(channels[3]);
  pixel.index=(MagickRealType) ScaleShortToQuantum(channels[4]);
  return(pixel);
}

static MagickPixelPacket GetMinimumPixelList(PixelList *pixel_list)
{
  MagickPixelPacket
    pixel;

  register SkipList
    *list;

  register ssize_t
    channel;

  size_t
    color,
    minimum;

  ssize_t
    count;

  unsigned short
    channels[ListChannels];

  /*
    Find the minimum value for each of the color.
  */
  for (channel=0; channel < 5; channel++)
  {
    list=pixel_list->lists+channel;
    count=0;
    color=65536UL;
    minimum=list->nodes[color].next[0];
    do
    {
      color=list->nodes[color].next[0];
      if (color < minimum)
        minimum=color;
      count+=list->nodes[color].count;
    } while (count < (ssize_t) pixel_list->length);
    channels[channel]=(unsigned short) minimum;
  }
  GetMagickPixelPacket((const Image *) NULL,&pixel);
  pixel.red=(MagickRealType) ScaleShortToQuantum(channels[0]);
  pixel.green=(MagickRealType) ScaleShortToQuantum(channels[1]);
  pixel.blue=(MagickRealType) ScaleShortToQuantum(channels[2]);
  pixel.opacity=(MagickRealType) ScaleShortToQuantum(channels[3]);
  pixel.index=(MagickRealType) ScaleShortToQuantum(channels[4]);
  return(pixel);
}

static MagickPixelPacket GetModePixelList(PixelList *pixel_list)
{
  MagickPixelPacket
    pixel;

  register SkipList
    *list;

  register ssize_t
    channel;

  size_t
    color,
    max_count,
    mode;

  ssize_t
    count;

  unsigned short
    channels[5];

  /*
    Make each pixel the 'predominate color' of the specified neighborhood.
  */
  for (channel=0; channel < 5; channel++)
  {
    list=pixel_list->lists+channel;
    color=65536L;
    mode=color;
    max_count=list->nodes[mode].count;
    count=0;
    do
    {
      color=list->nodes[color].next[0];
      if (list->nodes[color].count > max_count)
        {
          mode=color;
          max_count=list->nodes[mode].count;
        }
      count+=list->nodes[color].count;
    } while (count < (ssize_t) pixel_list->length);
    channels[channel]=(unsigned short) mode;
  }
  GetMagickPixelPacket((const Image *) NULL,&pixel);
  pixel.red=(MagickRealType) ScaleShortToQuantum(channels[0]);
  pixel.green=(MagickRealType) ScaleShortToQuantum(channels[1]);
  pixel.blue=(MagickRealType) ScaleShortToQuantum(channels[2]);
  pixel.opacity=(MagickRealType) ScaleShortToQuantum(channels[3]);
  pixel.index=(MagickRealType) ScaleShortToQuantum(channels[4]);
  return(pixel);
}

static MagickPixelPacket GetNonpeakPixelList(PixelList *pixel_list)
{
  MagickPixelPacket
    pixel;

  register SkipList
    *list;

  register ssize_t
    channel;

  size_t
    color,
    next,
    previous;

  ssize_t
    count;

  unsigned short
    channels[5];

  /*
    Finds the non peak value for each of the colors.
  */
  for (channel=0; channel < 5; channel++)
  {
    list=pixel_list->lists+channel;
    color=65536L;
    next=list->nodes[color].next[0];
    count=0;
    do
    {
      previous=color;
      color=next;
      next=list->nodes[color].next[0];
      count+=list->nodes[color].count;
    } while (count <= (ssize_t) (pixel_list->length >> 1));
    if ((previous == 65536UL) && (next != 65536UL))
      color=next;
    else
      if ((previous != 65536UL) && (next == 65536UL))
        color=previous;
    channels[channel]=(unsigned short) color;
  }
  GetMagickPixelPacket((const Image *) NULL,&pixel);
  pixel.red=(MagickRealType) ScaleShortToQuantum(channels[0]);
  pixel.green=(MagickRealType) ScaleShortToQuantum(channels[1]);
  pixel.blue=(MagickRealType) ScaleShortToQuantum(channels[2]);
  pixel.opacity=(MagickRealType) ScaleShortToQuantum(channels[3]);
  pixel.index=(MagickRealType) ScaleShortToQuantum(channels[4]);
  return(pixel);
}

static MagickPixelPacket GetStandardDeviationPixelList(PixelList *pixel_list)
{
  MagickPixelPacket
    pixel;

  MagickRealType
    sum,
    sum_squared;

  register SkipList
    *list;

  register ssize_t
    channel;

  size_t
    color;

  ssize_t
    count;

  unsigned short
    channels[ListChannels];

  /*
    Find the standard-deviation value for each of the color.
  */
  for (channel=0; channel < 5; channel++)
  {
    list=pixel_list->lists+channel;
    color=65536L;
    count=0;
    sum=0.0;
    sum_squared=0.0;
    do
    {
      register ssize_t
        i;

      color=list->nodes[color].next[0];
      sum+=(MagickRealType) list->nodes[color].count*color;
      for (i=0; i < (ssize_t) list->nodes[color].count; i++)
        sum_squared+=((MagickRealType) color)*((MagickRealType) color);
      count+=list->nodes[color].count;
    } while (count < (ssize_t) pixel_list->length);
    sum/=pixel_list->length;
    sum_squared/=pixel_list->length;
    channels[channel]=(unsigned short) sqrt(sum_squared-(sum*sum));
  }
  GetMagickPixelPacket((const Image *) NULL,&pixel);
  pixel.red=(MagickRealType) ScaleShortToQuantum(channels[0]);
  pixel.green=(MagickRealType) ScaleShortToQuantum(channels[1]);
  pixel.blue=(MagickRealType) ScaleShortToQuantum(channels[2]);
  pixel.opacity=(MagickRealType) ScaleShortToQuantum(channels[3]);
  pixel.index=(MagickRealType) ScaleShortToQuantum(channels[4]);
  return(pixel);
}

static inline void InsertPixelList(const Image *image,const PixelPacket *pixel,
  const IndexPacket *indexes,PixelList *pixel_list)
{
  size_t
    signature;

  unsigned short
    index;

  index=ScaleQuantumToShort(pixel->red);
  signature=pixel_list->lists[0].nodes[index].signature;
  if (signature == pixel_list->signature)
    pixel_list->lists[0].nodes[index].count++;
  else
    AddNodePixelList(pixel_list,0,index);
  index=ScaleQuantumToShort(pixel->green);
  signature=pixel_list->lists[1].nodes[index].signature;
  if (signature == pixel_list->signature)
    pixel_list->lists[1].nodes[index].count++;
  else
    AddNodePixelList(pixel_list,1,index);
  index=ScaleQuantumToShort(pixel->blue);
  signature=pixel_list->lists[2].nodes[index].signature;
  if (signature == pixel_list->signature)
    pixel_list->lists[2].nodes[index].count++;
  else
    AddNodePixelList(pixel_list,2,index);
  index=ScaleQuantumToShort(pixel->opacity);
  signature=pixel_list->lists[3].nodes[index].signature;
  if (signature == pixel_list->signature)
    pixel_list->lists[3].nodes[index].count++;
  else
    AddNodePixelList(pixel_list,3,index);
  if (image->colorspace == CMYKColorspace)
    index=ScaleQuantumToShort(*indexes);
  signature=pixel_list->lists[4].nodes[index].signature;
  if (signature == pixel_list->signature)
    pixel_list->lists[4].nodes[index].count++;
  else
    AddNodePixelList(pixel_list,4,index);
}

static inline MagickRealType MagickAbsoluteValue(const MagickRealType x)
{
  if (x < 0)
    return(-x);
  return(x);
}

static void ResetPixelList(PixelList *pixel_list)
{
  int
    level;

  register ListNode
    *root;

  register SkipList
    *list;

  register ssize_t
    channel;

  /*
    Reset the skip-list.
  */
  for (channel=0; channel < 5; channel++)
  {
    list=pixel_list->lists+channel;
    root=list->nodes+65536UL;
    list->level=0;
    for (level=0; level < 9; level++)
      root->next[level]=65536UL;
  }
  pixel_list->seed=pixel_list->signature++;
}

MagickExport Image *StatisticImage(const Image *image,const StatisticType type,
  const size_t width,const size_t height,ExceptionInfo *exception)
{
  Image
    *statistic_image;

  statistic_image=StatisticImageChannel(image,DefaultChannels,type,width,
    height,exception);
  return(statistic_image);
}

MagickExport Image *StatisticImageChannel(const Image *image,
  const ChannelType channel,const StatisticType type,const size_t width,
  const size_t height,ExceptionInfo *exception)
{
#define StatisticWidth \
  (width == 0 ? GetOptimalKernelWidth2D((double) width,0.5) : width)
#define StatisticHeight \
  (height == 0 ? GetOptimalKernelWidth2D((double) height,0.5) : height)
#define StatisticImageTag  "Statistic/Image"

  CacheView
    *image_view,
    *statistic_view;

  Image
    *statistic_image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  PixelList
    **restrict pixel_list;

  ssize_t
    y;

  /*
    Initialize statistics image attributes.
  */
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  statistic_image=CloneImage(image,image->columns,image->rows,MagickTrue,
    exception);
  if (statistic_image == (Image *) NULL)
    return((Image *) NULL);
  if (SetImageStorageClass(statistic_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&statistic_image->exception);
      statistic_image=DestroyImage(statistic_image);
      return((Image *) NULL);
    }
  pixel_list=AcquirePixelListThreadSet(StatisticWidth,StatisticHeight);
  if (pixel_list == (PixelList **) NULL)
    {
      statistic_image=DestroyImage(statistic_image);
      ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
    }
  /*
    Make each pixel the min / max / median / mode / etc. of the neighborhood.
  */
  status=MagickTrue;
  progress=0;
  image_view=AcquireCacheView(image);
  statistic_view=AcquireCacheView(statistic_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
  for (y=0; y < (ssize_t) statistic_image->rows; y++)
  {
    const int
      id = GetOpenMPThreadId();

    register const IndexPacket
      *restrict indexes;

    register const PixelPacket
      *restrict p;

    register IndexPacket
      *restrict statistic_indexes;

    register PixelPacket
      *restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    p=GetCacheViewVirtualPixels(image_view,-((ssize_t) StatisticWidth/2L),y-
      (ssize_t) (StatisticHeight/2L),image->columns+StatisticWidth,
      StatisticHeight,exception);
    q=QueueCacheViewAuthenticPixels(statistic_view,0,y,statistic_image->columns,      1,exception);
    if ((p == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
      {
        status=MagickFalse;
        continue;
      }
    indexes=GetCacheViewVirtualIndexQueue(image_view);
    statistic_indexes=GetCacheViewAuthenticIndexQueue(statistic_view);
    for (x=0; x < (ssize_t) statistic_image->columns; x++)
    {
      MagickPixelPacket
        pixel;

      register const IndexPacket
        *restrict s;

      register const PixelPacket
        *restrict r;

      register ssize_t
        u,
        v;

      r=p;
      s=indexes+x;
      ResetPixelList(pixel_list[id]);
      for (v=0; v < (ssize_t) StatisticHeight; v++)
      {
        for (u=0; u < (ssize_t) StatisticWidth; u++)
          InsertPixelList(image,r+u,s+u,pixel_list[id]);
        r+=image->columns+StatisticWidth;
        s+=image->columns+StatisticWidth;
      }
      GetMagickPixelPacket(image,&pixel);
      SetMagickPixelPacket(image,p+StatisticWidth*StatisticHeight/2,indexes+
        StatisticWidth*StatisticHeight/2+x,&pixel);
      switch (type)
      {
        case GradientStatistic:
        {
          MagickPixelPacket
            maximum,
            minimum;

          minimum=GetMinimumPixelList(pixel_list[id]);
          maximum=GetMaximumPixelList(pixel_list[id]);
          pixel.red=MagickAbsoluteValue(maximum.red-minimum.red);
          pixel.green=MagickAbsoluteValue(maximum.green-minimum.green);
          pixel.blue=MagickAbsoluteValue(maximum.blue-minimum.blue);
          pixel.opacity=MagickAbsoluteValue(maximum.opacity-minimum.opacity);
          if (image->colorspace == CMYKColorspace)
            pixel.index=MagickAbsoluteValue(maximum.index-minimum.index);
          break;
        }
        case MaximumStatistic:
        {
          pixel=GetMaximumPixelList(pixel_list[id]);
          break;
        }
        case MeanStatistic:
        {
          pixel=GetMeanPixelList(pixel_list[id]);
          break;
        }
        case MedianStatistic:
        default:
        {
          pixel=GetMedianPixelList(pixel_list[id]);
          break;
        }
        case MinimumStatistic:
        {
          pixel=GetMinimumPixelList(pixel_list[id]);
          break;
        }
        case ModeStatistic:
        {
          pixel=GetModePixelList(pixel_list[id]);
          break;
        }
        case NonpeakStatistic:
        {
          pixel=GetNonpeakPixelList(pixel_list[id]);
          break;
        }
        case StandardDeviationStatistic:
        {
          pixel=GetStandardDeviationPixelList(pixel_list[id]);
          break;
        }
      }
      if ((channel & RedChannel) != 0)
        q->red=ClampToQuantum(pixel.red);
      if ((channel & GreenChannel) != 0)
        q->green=ClampToQuantum(pixel.green);
      if ((channel & BlueChannel) != 0)
        q->blue=ClampToQuantum(pixel.blue);
      if (((channel & OpacityChannel) != 0) &&
          (image->matte != MagickFalse))
        q->opacity=ClampToQuantum(pixel.opacity);
      if (((channel & IndexChannel) != 0) &&
          (image->colorspace == CMYKColorspace))
        statistic_indexes[x]=(IndexPacket) ClampToQuantum(pixel.index);
      p++;
      q++;
    }
    if (SyncCacheViewAuthenticPixels(statistic_view,exception) == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_StatisticImage)
#endif
        proceed=SetImageProgress(image,StatisticImageTag,progress++,
          image->rows);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  statistic_view=DestroyCacheView(statistic_view);
  image_view=DestroyCacheView(image_view);
  pixel_list=DestroyPixelListThreadSet(pixel_list);
  return(statistic_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     U n s h a r p M a s k I m a g e                                         %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  UnsharpMaskImage() sharpens one or more image channels.  We convolve the
%  image with a Gaussian operator of the given radius and standard deviation
%  (sigma).  For reasonable results, radius should be larger than sigma.  Use a
%  radius of 0 and UnsharpMaskImage() selects a suitable radius for you.
%
%  The format of the UnsharpMaskImage method is:
%
%    Image *UnsharpMaskImage(const Image *image,const double radius,
%      const double sigma,const double amount,const double threshold,
%      ExceptionInfo *exception)
%    Image *UnsharpMaskImageChannel(const Image *image,
%      const ChannelType channel,const double radius,const double sigma,
%      const double amount,const double threshold,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: the channel type.
%
%    o radius: the radius of the Gaussian, in pixels, not counting the center
%      pixel.
%
%    o sigma: the standard deviation of the Gaussian, in pixels.
%
%    o amount: the percentage of the difference between the original and the
%      blur image that is added back into the original.
%
%    o threshold: the threshold in pixels needed to apply the diffence amount.
%
%    o exception: return any errors or warnings in this structure.
%
*/

MagickExport Image *UnsharpMaskImage(const Image *image,const double radius,
  const double sigma,const double amount,const double threshold,
  ExceptionInfo *exception)
{
  Image
    *sharp_image;

  sharp_image=UnsharpMaskImageChannel(image,DefaultChannels,radius,sigma,amount,
    threshold,exception);
  return(sharp_image);
}

MagickExport Image *UnsharpMaskImageChannel(const Image *image,
  const ChannelType channel,const double radius,const double sigma,
  const double amount,const double threshold,ExceptionInfo *exception)
{
#define SharpenImageTag  "Sharpen/Image"

  CacheView
    *image_view,
    *unsharp_view;

  Image
    *unsharp_image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  MagickPixelPacket
    bias;

  MagickRealType
    quantum_threshold;

  ssize_t
    y;

  assert(image != (const Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  unsharp_image=BlurImageChannel(image,channel,radius,sigma,exception);
  if (unsharp_image == (Image *) NULL)
    return((Image *) NULL);
  quantum_threshold=(MagickRealType) QuantumRange*threshold;
  /*
    Unsharp-mask image.
  */
  status=MagickTrue;
  progress=0;
  GetMagickPixelPacket(image,&bias);
  image_view=AcquireCacheView(image);
  unsharp_view=AcquireCacheView(unsharp_image);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
  for (y=0; y < (ssize_t) image->rows; y++)
  {
    MagickPixelPacket
      pixel;

    register const IndexPacket
      *restrict indexes;

    register const PixelPacket
      *restrict p;

    register IndexPacket
      *restrict unsharp_indexes;

    register PixelPacket
      *restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
    q=GetCacheViewAuthenticPixels(unsharp_view,0,y,unsharp_image->columns,1,
      exception);
    if ((p == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
      {
        status=MagickFalse;
        continue;
      }
    indexes=GetCacheViewVirtualIndexQueue(image_view);
    unsharp_indexes=GetCacheViewAuthenticIndexQueue(unsharp_view);
    pixel=bias;
    for (x=0; x < (ssize_t) image->columns; x++)
    {
      if ((channel & RedChannel) != 0)
        {
          pixel.red=p->red-(MagickRealType) q->red;
          if (fabs(2.0*pixel.red) < quantum_threshold)
            pixel.red=(MagickRealType) GetRedPixelComponent(p);
          else
            pixel.red=(MagickRealType) p->red+(pixel.red*amount);
          SetRedPixelComponent(q,ClampRedPixelComponent(&pixel));
        }
      if ((channel & GreenChannel) != 0)
        {
          pixel.green=p->green-(MagickRealType) q->green;
          if (fabs(2.0*pixel.green) < quantum_threshold)
            pixel.green=(MagickRealType) GetGreenPixelComponent(p);
          else
            pixel.green=(MagickRealType) p->green+(pixel.green*amount);
          SetGreenPixelComponent(q,ClampGreenPixelComponent(&pixel));
        }
      if ((channel & BlueChannel) != 0)
        {
          pixel.blue=p->blue-(MagickRealType) q->blue;
          if (fabs(2.0*pixel.blue) < quantum_threshold)
            pixel.blue=(MagickRealType) GetBluePixelComponent(p);
          else
            pixel.blue=(MagickRealType) p->blue+(pixel.blue*amount);
          SetBluePixelComponent(q,ClampBluePixelComponent(&pixel));
        }
      if ((channel & OpacityChannel) != 0)
        {
          pixel.opacity=p->opacity-(MagickRealType) q->opacity;
          if (fabs(2.0*pixel.opacity) < quantum_threshold)
            pixel.opacity=(MagickRealType) GetOpacityPixelComponent(p);
          else
            pixel.opacity=p->opacity+(pixel.opacity*amount);
          SetOpacityPixelComponent(q,ClampOpacityPixelComponent(&pixel));
        }
      if (((channel & IndexChannel) != 0) &&
          (image->colorspace == CMYKColorspace))
        {
          pixel.index=indexes[x]-(MagickRealType) unsharp_indexes[x];
          if (fabs(2.0*pixel.index) < quantum_threshold)
            pixel.index=(MagickRealType) indexes[x];
          else
            pixel.index=(MagickRealType) indexes[x]+(pixel.index*amount);
          unsharp_indexes[x]=ClampToQuantum(pixel.index);
        }
      p++;
      q++;
    }
    if (SyncCacheViewAuthenticPixels(unsharp_view,exception) == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp critical (MagickCore_UnsharpMaskImageChannel)
#endif
        proceed=SetImageProgress(image,SharpenImageTag,progress++,image->rows);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  unsharp_image->type=image->type;
  unsharp_view=DestroyCacheView(unsharp_view);
  image_view=DestroyCacheView(image_view);
  if (status == MagickFalse)
    unsharp_image=DestroyImage(unsharp_image);
  return(unsharp_image);
}

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