root/coders/psd.c

DEFINITIONS

1. IsPSD
2. CompositeOperatorToPSDBlendMode
3. CorrectPSDAlphaBlend
4. ConvertPSDCompression
5. CorrectPSDOpacity
6. DecodePSDPixels
7. DestroyLayerInfo
8. GetPSDPacketSize
9. GetPSDSize
10. GetPSDRowSize
11. ModeToString
12. ParseImageResourceBlocks
13. PSDBlendModeToCompositeOperator
14. ReversePSDString
15. ReadPSDChannelPixels
16. ReadPSDChannelRaw
17. ReadPSDRLEOffsets
18. ReadPSDChannelRLE
19. ReadPSDChannelZip
20. ReadPSDChannel
21. ReadPSDLayer
22. ReadPSDLayers
23. ReadPSDMergedImage
24. ReadPSDImage
25. RegisterPSDImage
26. UnregisterPSDImage
27. SetPSDOffset
28. SetPSDSize
29. PSDPackbitsEncodeImage
30. WritePackbitsLength
31. WriteOneChannel
32. WriteImageChannels
33. WritePascalString
34. WriteResolutionResourceBlock
35. RemoveICCProfileFromResourceBlock
36. RemoveResolutionFromResourceBlock
37. WritePSDImage

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%                            PPPP   SSSSS  DDDD                               %
%                            P   P  SS     D   D                              %
%                            PPPP    SSS   D   D                              %
%                            P         SS  D   D                              %
%                            P      SSSSS  DDDD                               %
%                                                                             %
%                                                                             %
%                   Read/Write Adobe Photoshop Image Format                   %
%                                                                             %
%                              Software Design                                %
%                                   Cristy                                    %
%                              Leonard Rosenthol                              %
%                                 July 1992                                   %
%                                Dirk Lemstra                                 %
%                                December 2013                                %
%                                                                             %
%                                                                             %
%  Copyright 1999-2016 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/artifact.h"
#include "magick/attribute.h"
#include "magick/blob.h"
#include "magick/blob-private.h"
#include "magick/cache.h"
#include "magick/channel.h"
#include "magick/colormap.h"
#include "magick/colormap-private.h"
#include "magick/colorspace.h"
#include "magick/colorspace-private.h"
#include "magick/constitute.h"
#include "magick/enhance.h"
#include "magick/exception.h"
#include "magick/exception-private.h"
#include "magick/image.h"
#include "magick/image-private.h"
#include "magick/list.h"
#include "magick/log.h"
#include "magick/magick.h"
#include "magick/memory_.h"
#include "magick/module.h"
#include "magick/monitor-private.h"
#include "magick/option.h"
#include "magick/pixel.h"
#include "magick/pixel-accessor.h"
#include "magick/profile.h"
#include "magick/property.h"
#include "magick/quantum-private.h"
#include "magick/static.h"
#include "magick/string_.h"
#include "magick/thread-private.h"
#ifdef MAGICKCORE_ZLIB_DELEGATE
#include <zlib.h>
#endif
#include "psd-private.h"

/*
  Define declaractions.
*/
#define MaxPSDChannels  56
#define PSDQuantum(x) (((ssize_t) (x)+1) & -2)

/*
  Enumerated declaractions.
*/
typedef enum
{
  Raw = 0,
  RLE = 1,
  ZipWithoutPrediction = 2,
  ZipWithPrediction = 3
} PSDCompressionType;

typedef enum
{
  BitmapMode = 0,
  GrayscaleMode = 1,
  IndexedMode = 2,
  RGBMode = 3,
  CMYKMode = 4,
  MultichannelMode = 7,
  DuotoneMode = 8,
  LabMode = 9
} PSDImageType;

/*
  Typedef declaractions.
*/
typedef struct _ChannelInfo
{
  short int
    type;

  size_t
    size;
} ChannelInfo;

typedef struct _MaskInfo
{
  Image
    *image;

  RectangleInfo
    page;

  unsigned char
    background,
    flags;
} MaskInfo;

typedef struct _LayerInfo
{
  ChannelInfo
    channel_info[MaxPSDChannels];

  char
    blendkey[4];

  Image
    *image;

  MaskInfo
    mask;

  Quantum
    opacity;

  RectangleInfo
    page;

  size_t
    offset_x,
    offset_y;

  unsigned char
    clipping,
    flags,
    name[256],
    visible;

  unsigned short
    channels;
} LayerInfo;

/*
  Forward declarations.
*/
static MagickBooleanType
  WritePSDImage(const ImageInfo *,Image *);

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   I s P S D                                                                 %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  IsPSD()() returns MagickTrue if the image format type, identified by the
%  magick string, is PSD.
%
%  The format of the IsPSD method is:
%
%      MagickBooleanType IsPSD(const unsigned char *magick,const size_t length)
%
%  A description of each parameter follows:
%
%    o magick: compare image format pattern against these bytes.
%
%    o length: Specifies the length of the magick string.
%
*/
static MagickBooleanType IsPSD(const unsigned char *magick,const size_t length)
{
  if (length < 4)
    return(MagickFalse);
  if (LocaleNCompare((const char *) magick,"8BPS",4) == 0)
    return(MagickTrue);
  return(MagickFalse);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   R e a d P S D I m a g e                                                   %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  ReadPSDImage() reads an Adobe Photoshop image file and returns it.  It
%  allocates the memory necessary for the new Image structure and returns a
%  pointer to the new image.
%
%  The format of the ReadPSDImage method is:
%
%      Image *ReadPSDImage(image_info,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image_info: the image info.
%
%    o exception: return any errors or warnings in this structure.
%
*/

static const char *CompositeOperatorToPSDBlendMode(CompositeOperator op)
{
  const char
    *blend_mode;

  switch (op)
  {
    case ColorBurnCompositeOp:  blend_mode = "idiv";  break;
    case ColorDodgeCompositeOp: blend_mode = "div ";  break;
    case ColorizeCompositeOp:   blend_mode = "colr";  break;
    case DarkenCompositeOp:     blend_mode = "dark";  break;
    case DifferenceCompositeOp: blend_mode = "diff";  break;
    case DissolveCompositeOp:   blend_mode = "diss";  break;
    case ExclusionCompositeOp:  blend_mode = "smud";  break;
    case HardLightCompositeOp:  blend_mode = "hLit";  break;
    case HardMixCompositeOp:    blend_mode = "hMix";  break;
    case HueCompositeOp:        blend_mode = "hue ";  break;
    case LightenCompositeOp:    blend_mode = "lite";  break;
    case LinearBurnCompositeOp: blend_mode = "lbrn";  break;
    case LinearDodgeCompositeOp:blend_mode = "lddg";  break;
    case LinearLightCompositeOp:blend_mode = "lLit";  break;
    case LuminizeCompositeOp:   blend_mode = "lum ";  break;
    case MultiplyCompositeOp:   blend_mode = "mul ";  break;
    case OverCompositeOp:       blend_mode = "norm";  break;
    case OverlayCompositeOp:    blend_mode = "over";  break;
    case PinLightCompositeOp:   blend_mode = "pLit";  break;
    case SaturateCompositeOp:   blend_mode = "sat ";  break;
    case ScreenCompositeOp:     blend_mode = "scrn";  break;
    case SoftLightCompositeOp:  blend_mode = "sLit";  break;
    case VividLightCompositeOp: blend_mode = "vLit";  break;
    default:                    blend_mode = "norm";  break;
  }
  return(blend_mode);
}

/*
For some reason Photoshop seems to blend semi-transparent pixels with white.
This method reverts the blending. This can be disabled by setting the
option 'psd:alpha-unblend' to off.
*/
static MagickBooleanType CorrectPSDAlphaBlend(const ImageInfo *image_info,
  Image *image, ExceptionInfo* exception)
{
  const char
    *option;

  MagickBooleanType
    status;

  ssize_t
    y;

  if (image->matte == MagickFalse || image->colorspace != sRGBColorspace)
    return(MagickTrue);
  option=GetImageOption(image_info,"psd:alpha-unblend");
  if (IsStringNotFalse(option) == MagickFalse)
    return(MagickTrue);
  status=MagickTrue;
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static,4) shared(status) \
  magick_threads(image,image,image->rows,1)
#endif
  for (y=0; y < (ssize_t) image->rows; y++)
  {
    register PixelPacket
      *magick_restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    q=GetAuthenticPixels(image,0,y,image->columns,1,exception);
    if (q == (PixelPacket *) NULL)
      {
        status=MagickFalse;
        continue;
      }
    for (x=0; x < (ssize_t) image->columns; x++)
    {
      double
        gamma;

      gamma=QuantumScale*GetPixelAlpha(q);
      if (gamma != 0.0 && gamma != 1.0)
        {
          SetPixelRed(q,(GetPixelRed(q)-((1.0-gamma)*QuantumRange))/gamma);
          SetPixelGreen(q,(GetPixelGreen(q)-((1.0-gamma)*QuantumRange))/gamma);
          SetPixelBlue(q,(GetPixelBlue(q)-((1.0-gamma)*QuantumRange))/gamma);
        }
      q++;
    }
    if (SyncAuthenticPixels(image,exception) == MagickFalse)
      status=MagickFalse;
  }

  return(status);
}

static inline CompressionType ConvertPSDCompression(
  PSDCompressionType compression)
{
  switch (compression)
  {
    case RLE:
      return RLECompression;
    case ZipWithPrediction:
    case ZipWithoutPrediction:
      return ZipCompression;
    default:
      return NoCompression;
  }
}

static MagickBooleanType CorrectPSDOpacity(LayerInfo* layer_info,
  ExceptionInfo *exception)
{
  MagickBooleanType
    status;

  ssize_t
    y;

  if (layer_info->opacity == OpaqueOpacity)
    return(MagickTrue);

  layer_info->image->matte=MagickTrue;
  status=MagickTrue;
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static,4) shared(status) \
  magick_threads(layer_info->image,layer_info->image,layer_info->image->rows,1)
#endif
  for (y=0; y < (ssize_t) layer_info->image->rows; y++)
  {
    register PixelPacket
      *magick_restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    q=GetAuthenticPixels(layer_info->image,0,y,layer_info->image->columns,1,
      exception);
    if (q == (PixelPacket *)NULL)
      {
        status=MagickFalse;
        continue;
      }
    for (x=0; x < (ssize_t) layer_info->image->columns; x++)
    {
      q->opacity=(Quantum) (QuantumRange-(Quantum) (QuantumScale*(
        (QuantumRange-q->opacity)*(QuantumRange-layer_info->opacity))));
      q++;
    }
    if (SyncAuthenticPixels(layer_info->image,exception) == MagickFalse)
      status=MagickFalse;
  }
  return(status);
}

static ssize_t DecodePSDPixels(const size_t number_compact_pixels,
  const unsigned char *compact_pixels,const ssize_t depth,
  const size_t number_pixels,unsigned char *pixels)
{
#define CheckNumberPixels(count) \
  if (((ssize_t) i + count) > (ssize_t) number_pixels) \
    return(i); \
  i+=count

  int
    pixel;

  register ssize_t
    i,
    j;

  size_t
    length;

  ssize_t
    packets;

  packets=(ssize_t) number_compact_pixels;
  for (i=0; (packets > 1) && (i < (ssize_t) number_pixels); )
  {
    packets--;
    length=(size_t) (*compact_pixels++);
    if (length == 128)
      continue;
    if (length > 128)
      {
        length=256-length+1;
        packets--;
        pixel=(*compact_pixels++);
        for (j=0; j < (ssize_t) length; j++)
        {
          switch (depth)
          {
            case 1:
            {
              CheckNumberPixels(8);
              *pixels++=(pixel >> 7) & 0x01 ? 0U : 255U;
              *pixels++=(pixel >> 6) & 0x01 ? 0U : 255U;
              *pixels++=(pixel >> 5) & 0x01 ? 0U : 255U;
              *pixels++=(pixel >> 4) & 0x01 ? 0U : 255U;
              *pixels++=(pixel >> 3) & 0x01 ? 0U : 255U;
              *pixels++=(pixel >> 2) & 0x01 ? 0U : 255U;
              *pixels++=(pixel >> 1) & 0x01 ? 0U : 255U;
              *pixels++=(pixel >> 0) & 0x01 ? 0U : 255U;
              break;
            }
            case 2:
            {
              CheckNumberPixels(4);
              *pixels++=(unsigned char) ((pixel >> 6) & 0x03);
              *pixels++=(unsigned char) ((pixel >> 4) & 0x03);
              *pixels++=(unsigned char) ((pixel >> 2) & 0x03);
              *pixels++=(unsigned char) ((pixel & 0x03) & 0x03);
              break;
            }
            case 4:
            {
              CheckNumberPixels(2);
              *pixels++=(unsigned char) ((pixel >> 4) & 0xff);
              *pixels++=(unsigned char) ((pixel & 0x0f) & 0xff);
              break;
            }
            default:
            {
              CheckNumberPixels(1);
              *pixels++=(unsigned char) pixel;
              break;
            }
          }
        }
        continue;
      }
    length++;
    for (j=0; j < (ssize_t) length; j++)
    {
      switch (depth)
      {
        case 1:
        {
          CheckNumberPixels(8);
          *pixels++=(*compact_pixels >> 7) & 0x01 ? 0U : 255U;
          *pixels++=(*compact_pixels >> 6) & 0x01 ? 0U : 255U;
          *pixels++=(*compact_pixels >> 5) & 0x01 ? 0U : 255U;
          *pixels++=(*compact_pixels >> 4) & 0x01 ? 0U : 255U;
          *pixels++=(*compact_pixels >> 3) & 0x01 ? 0U : 255U;
          *pixels++=(*compact_pixels >> 2) & 0x01 ? 0U : 255U;
          *pixels++=(*compact_pixels >> 1) & 0x01 ? 0U : 255U;
          *pixels++=(*compact_pixels >> 0) & 0x01 ? 0U : 255U;
          break;
        }
        case 2:
        {
          CheckNumberPixels(4);
          *pixels++=(*compact_pixels >> 6) & 0x03;
          *pixels++=(*compact_pixels >> 4) & 0x03;
          *pixels++=(*compact_pixels >> 2) & 0x03;
          *pixels++=(*compact_pixels & 0x03) & 0x03;
          break;
        }
        case 4:
        {
          CheckNumberPixels(2);
          *pixels++=(*compact_pixels >> 4) & 0xff;
          *pixels++=(*compact_pixels & 0x0f) & 0xff;
          break;
        }
        default:
        {
          CheckNumberPixels(1);
          *pixels++=(*compact_pixels);
          break;
        }
      }
      if (packets == 0)
        return(i);
      packets--;
      compact_pixels++;
    }
  }
  return(i);
}

static inline LayerInfo *DestroyLayerInfo(LayerInfo *layer_info,
  const ssize_t number_layers)
{
  ssize_t
    i;

  for (i=0; i<number_layers; i++)
  {
    if (layer_info[i].image != (Image *) NULL)
      layer_info[i].image=DestroyImage(layer_info[i].image);
    if (layer_info[i].mask.image != (Image *) NULL)
      layer_info[i].mask.image=DestroyImage(layer_info[i].mask.image);
  }

  return (LayerInfo *) RelinquishMagickMemory(layer_info);
}

static inline size_t GetPSDPacketSize(Image *image)
{
  if (image->storage_class == PseudoClass)
    {
      if (image->colors > 256)
        return(2);
      else if (image->depth > 8)
        return(2);
    }
  else
    if (image->depth > 8)
      return(2);

  return(1);
}

static inline MagickSizeType GetPSDSize(const PSDInfo *psd_info,Image *image)
{
  if (psd_info->version == 1)
    return((MagickSizeType) ReadBlobLong(image));
  return((MagickSizeType) ReadBlobLongLong(image));
}

static inline size_t GetPSDRowSize(Image *image)
{
  if (image->depth == 1)
    return((image->columns+7)/8);
  else
    return(image->columns*GetPSDPacketSize(image));
}

static const char *ModeToString(PSDImageType type)
{
  switch (type)
  {
    case BitmapMode: return "Bitmap";
    case GrayscaleMode: return "Grayscale";
    case IndexedMode: return "Indexed";
    case RGBMode: return "RGB";
    case CMYKMode:  return "CMYK";
    case MultichannelMode: return "Multichannel";
    case DuotoneMode: return "Duotone";
    case LabMode: return "L*A*B";
    default: return "unknown";
  }
}

static void ParseImageResourceBlocks(Image *image,
  const unsigned char *blocks,size_t length,
  MagickBooleanType *has_merged_image)
{
  const unsigned char
    *p;

  StringInfo
    *profile;

  unsigned int
    count,
    long_sans;

  unsigned short
    id,
    short_sans;

  if (length < 16)
    return;
  profile=BlobToStringInfo((const void *) NULL,length);
  SetStringInfoDatum(profile,blocks);
  (void) SetImageProfile(image,"8bim",profile);
  profile=DestroyStringInfo(profile);
  for (p=blocks; (p >= blocks) && (p < (blocks+length-16)); )
  {
    if (LocaleNCompare((const char *) p,"8BIM",4) != 0)
      break;
    p=PushLongPixel(MSBEndian,p,&long_sans);
    p=PushShortPixel(MSBEndian,p,&id);
    p=PushShortPixel(MSBEndian,p,&short_sans);
    p=PushLongPixel(MSBEndian,p,&count);
    if (p+count > blocks+length)
      return;
    switch (id)
    {
      case 0x03ed:
      {
        char
          value[MaxTextExtent];

        unsigned short
          resolution;

        /*
          Resolution info.
        */
        p=PushShortPixel(MSBEndian,p,&resolution);
        image->x_resolution=(double) resolution;
        (void) FormatLocaleString(value,MaxTextExtent,"%g",
          image->x_resolution);
        (void) SetImageProperty(image,"tiff:XResolution",value);
        p=PushShortPixel(MSBEndian,p,&short_sans);
        p=PushShortPixel(MSBEndian,p,&short_sans);
        p=PushShortPixel(MSBEndian,p,&short_sans);
        p=PushShortPixel(MSBEndian,p,&resolution);
        image->y_resolution=(double) resolution;
        (void) FormatLocaleString(value,MaxTextExtent,"%g",
          image->y_resolution);
        (void) SetImageProperty(image,"tiff:YResolution",value);
        p=PushShortPixel(MSBEndian,p,&short_sans);
        p=PushShortPixel(MSBEndian,p,&short_sans);
        p=PushShortPixel(MSBEndian,p,&short_sans);
        image->units=PixelsPerInchResolution;
        break;
      }
      case 0x0421:
      {
        if (*(p+4) == 0)
          *has_merged_image=MagickFalse;
        p+=count;
        break;
      }
      default:
      {
        p+=count;
        break;
      }
    }
    if ((count & 0x01) != 0)
      p++;
  }
  return;
}

static CompositeOperator PSDBlendModeToCompositeOperator(const char *mode)
{
  if (mode == (const char *) NULL)
    return(OverCompositeOp);
  if (LocaleNCompare(mode,"norm",4) == 0)
    return(OverCompositeOp);
  if (LocaleNCompare(mode,"mul ",4) == 0)
    return(MultiplyCompositeOp);
  if (LocaleNCompare(mode,"diss",4) == 0)
    return(DissolveCompositeOp);
  if (LocaleNCompare(mode,"diff",4) == 0)
    return(DifferenceCompositeOp);
  if (LocaleNCompare(mode,"dark",4) == 0)
    return(DarkenCompositeOp);
  if (LocaleNCompare(mode,"lite",4) == 0)
    return(LightenCompositeOp);
  if (LocaleNCompare(mode,"hue ",4) == 0)
    return(HueCompositeOp);
  if (LocaleNCompare(mode,"sat ",4) == 0)
    return(SaturateCompositeOp);
  if (LocaleNCompare(mode,"colr",4) == 0)
    return(ColorizeCompositeOp);
  if (LocaleNCompare(mode,"lum ",4) == 0)
    return(LuminizeCompositeOp);
  if (LocaleNCompare(mode,"scrn",4) == 0)
    return(ScreenCompositeOp);
  if (LocaleNCompare(mode,"over",4) == 0)
    return(OverlayCompositeOp);
  if (LocaleNCompare(mode,"hLit",4) == 0)
    return(HardLightCompositeOp);
  if (LocaleNCompare(mode,"sLit",4) == 0)
    return(SoftLightCompositeOp);
  if (LocaleNCompare(mode,"smud",4) == 0)
    return(ExclusionCompositeOp);
  if (LocaleNCompare(mode,"div ",4) == 0)
    return(ColorDodgeCompositeOp);
  if (LocaleNCompare(mode,"idiv",4) == 0)
    return(ColorBurnCompositeOp);
  if (LocaleNCompare(mode,"lbrn",4) == 0)
    return(LinearBurnCompositeOp);
  if (LocaleNCompare(mode,"lddg",4) == 0)
    return(LinearDodgeCompositeOp);
  if (LocaleNCompare(mode,"lLit",4) == 0)
    return(LinearLightCompositeOp);
  if (LocaleNCompare(mode,"vLit",4) == 0)
    return(VividLightCompositeOp);
  if (LocaleNCompare(mode,"pLit",4) == 0)
    return(PinLightCompositeOp);
  if (LocaleNCompare(mode,"hMix",4) == 0)
    return(HardMixCompositeOp);
  return(OverCompositeOp);
}

static inline void ReversePSDString(Image *image,char *p,size_t length)
{
  char
    *q;

  if (image->endian == MSBEndian)
    return;

  q=p+length;
  for(--q; p < q; ++p, --q)
  {
    *p = *p ^ *q,
    *q = *p ^ *q,
    *p = *p ^ *q;
  }
}

static MagickBooleanType ReadPSDChannelPixels(Image *image,const size_t channels,
  const size_t row,const ssize_t type,const unsigned char *pixels,
  ExceptionInfo *exception)
{
  Quantum
    pixel;

  register const unsigned char
    *p;

  register IndexPacket
    *indexes;

  register PixelPacket
    *q;

  register ssize_t
    x;

  size_t
    packet_size;

  unsigned short
    nibble;

  p=pixels;
  q=GetAuthenticPixels(image,0,row,image->columns,1,exception);
  if (q == (PixelPacket *) NULL)
    return MagickFalse;
  indexes=GetAuthenticIndexQueue(image);
  packet_size=GetPSDPacketSize(image);
  for (x=0; x < (ssize_t) image->columns; x++)
  {
    if (packet_size == 1)
      pixel=ScaleCharToQuantum(*p++);
    else
      {
        p=PushShortPixel(MSBEndian,p,&nibble);
        pixel=ScaleShortToQuantum(nibble);
      }
    switch (type)
    {
      case -1:
      {
        SetPixelAlpha(q,pixel);
        break;
      }
      case -2:
      case 0:
      {
        SetPixelRed(q,pixel);
        if (channels == 1 || type == -2)
          {
            SetPixelGreen(q,GetPixelRed(q));
            SetPixelBlue(q,GetPixelRed(q));
          }
        if (image->storage_class == PseudoClass)
          {
            if (packet_size == 1)
              SetPixelIndex(indexes+x,ScaleQuantumToChar(pixel));
            else
              SetPixelIndex(indexes+x,ScaleQuantumToShort(pixel));
            SetPixelRGBO(q,image->colormap+(ssize_t)
              ConstrainColormapIndex(image,GetPixelIndex(indexes+x)));
            if (image->depth == 1)
              {
                ssize_t
                  bit,
                  number_bits;

                number_bits=image->columns-x;
                if (number_bits > 8)
                  number_bits=8;
                for (bit=0; bit < number_bits; bit++)
                {
                  SetPixelIndex(indexes+x,(((unsigned char) pixel) &
                    (0x01 << (7-bit))) != 0 ? 0 : 255);
                  SetPixelRGBO(q,image->colormap+(ssize_t)
                    GetPixelIndex(indexes+x));
                  q++;
                  x++;
                }
                x--;
                continue;
              }
          }
        break;
      }
      case 1:
      {
        if (image->storage_class == PseudoClass)
          SetPixelAlpha(q,pixel);
        else
          SetPixelGreen(q,pixel);
        break;
      }
      case 2:
      {
        if (image->storage_class == PseudoClass)
          SetPixelAlpha(q,pixel);
        else
          SetPixelBlue(q,pixel);
        break;
      }
      case 3:
      {
        if (image->colorspace == CMYKColorspace)
          SetPixelIndex(indexes+x,pixel);
        else
          if (image->matte != MagickFalse)
            SetPixelAlpha(q,pixel);
        break;
      }
      case 4:
      {
        if ((IssRGBCompatibleColorspace(image->colorspace) != MagickFalse) &&
            (channels > 3))
          break;
        if (image->matte != MagickFalse)
          SetPixelAlpha(q,pixel);
        break;
      }
      default:
        break;
    }
    q++;
  }
  return(SyncAuthenticPixels(image,exception));
}

static MagickBooleanType ReadPSDChannelRaw(Image *image,const size_t channels,
  const ssize_t type,ExceptionInfo *exception)
{
  MagickBooleanType
    status;

  size_t
    count,
    row_size;

  ssize_t
    y;

  unsigned char
    *pixels;

  if (image->debug != MagickFalse)
    (void) LogMagickEvent(CoderEvent,GetMagickModule(),
       "      layer data is RAW");

  row_size=GetPSDRowSize(image);
  pixels=(unsigned char *) AcquireQuantumMemory(row_size,sizeof(*pixels));
  if (pixels == (unsigned char *) NULL)
    ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
      image->filename);

  status=MagickTrue;
  for (y=0; y < (ssize_t) image->rows; y++)
  {
    status=MagickFalse;

    count=ReadBlob(image,row_size,pixels);
    if (count != row_size)
      break;

    status=ReadPSDChannelPixels(image,channels,y,type,pixels,exception);
    if (status == MagickFalse)
      break;
  }

  pixels=(unsigned char *) RelinquishMagickMemory(pixels);
  return(status);
}

static inline MagickOffsetType *ReadPSDRLEOffsets(Image *image,
  const PSDInfo *psd_info,const size_t size)
{
  MagickOffsetType
    *offsets;

  ssize_t
    y;

  offsets=(MagickOffsetType *) AcquireQuantumMemory(size,sizeof(*offsets));
  if(offsets != (MagickOffsetType *) NULL)
    {
      for (y=0; y < (ssize_t) size; y++)
      {
        if (psd_info->version == 1)
          offsets[y]=(MagickOffsetType) ReadBlobShort(image);
        else
          offsets[y]=(MagickOffsetType) ReadBlobLong(image);
      }
    }
  return offsets;
}

static MagickBooleanType ReadPSDChannelRLE(Image *image,const PSDInfo *psd_info,
  const ssize_t type,MagickOffsetType *offsets,ExceptionInfo *exception)
{
  MagickBooleanType
    status;

  size_t
    length,
    row_size;

  ssize_t
    count,
    y;

  unsigned char
    *compact_pixels,
    *pixels;

  if (image->debug != MagickFalse)
    (void) LogMagickEvent(CoderEvent,GetMagickModule(),
       "      layer data is RLE compressed");

  row_size=GetPSDRowSize(image);
  pixels=(unsigned char *) AcquireQuantumMemory(row_size,sizeof(*pixels));
  if (pixels == (unsigned char *) NULL)
    ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
      image->filename);

  length=0;
  for (y=0; y < (ssize_t) image->rows; y++)
    if ((MagickOffsetType) length < offsets[y])
      length=(size_t) offsets[y];

  compact_pixels=(unsigned char *) AcquireQuantumMemory(length,sizeof(*pixels));
  if (compact_pixels == (unsigned char *) NULL)
    {
      pixels=(unsigned char *) RelinquishMagickMemory(pixels);
      ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
        image->filename);
    }

  (void) ResetMagickMemory(compact_pixels,0,length*sizeof(*compact_pixels));

  status=MagickTrue;
  for (y=0; y < (ssize_t) image->rows; y++)
  {
    status=MagickFalse;

    count=ReadBlob(image,(size_t) offsets[y],compact_pixels);
    if (count != (ssize_t) offsets[y])
      break;

    count=DecodePSDPixels((size_t) offsets[y],compact_pixels,
      (ssize_t) (image->depth == 1 ? 123456 : image->depth),row_size,pixels);
    if (count != (ssize_t) row_size)
      break;

    status=ReadPSDChannelPixels(image,psd_info->channels,y,type,pixels,
      exception);
    if (status == MagickFalse)
      break;
  }

  compact_pixels=(unsigned char *) RelinquishMagickMemory(compact_pixels);
  pixels=(unsigned char *) RelinquishMagickMemory(pixels);
  return(status);
}

#ifdef MAGICKCORE_ZLIB_DELEGATE
static MagickBooleanType ReadPSDChannelZip(Image *image,const size_t channels,
  const ssize_t type,const PSDCompressionType compression,
  const size_t compact_size,ExceptionInfo *exception)
{
  MagickBooleanType
    status;

  register unsigned char
    *p;

  size_t
    count,
    length,
    packet_size,
    row_size;

  ssize_t
    y;

  unsigned char
    *compact_pixels,
    *pixels;

  z_stream
    stream;

  if (image->debug != MagickFalse)
    (void) LogMagickEvent(CoderEvent,GetMagickModule(),
       "      layer data is ZIP compressed");

  compact_pixels=(unsigned char *) AcquireQuantumMemory(compact_size,
    sizeof(*compact_pixels));
  if (compact_pixels == (unsigned char *) NULL)
    ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
      image->filename);

  packet_size=GetPSDPacketSize(image);
  row_size=image->columns*packet_size;
  count=image->rows*row_size;

  pixels=(unsigned char *) AcquireQuantumMemory(count,sizeof(*pixels));
  if (pixels == (unsigned char *) NULL)
    {
      compact_pixels=(unsigned char *) RelinquishMagickMemory(compact_pixels);
      ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
        image->filename);
    }

  ResetMagickMemory(&stream, 0, sizeof(z_stream));
  stream.data_type=Z_BINARY;
  (void) ReadBlob(image,compact_size,compact_pixels);

  stream.next_in=(Bytef *)compact_pixels;
  stream.avail_in=(unsigned int) compact_size;
  stream.next_out=(Bytef *)pixels;
  stream.avail_out=(unsigned int) count;

  if(inflateInit(&stream) == Z_OK)
    {
      int
        ret;

      while (stream.avail_out > 0)
      {
        ret=inflate(&stream, Z_SYNC_FLUSH);
        if (ret != Z_OK && ret != Z_STREAM_END)
        {
          compact_pixels=(unsigned char *) RelinquishMagickMemory(
            compact_pixels);
          pixels=(unsigned char *) RelinquishMagickMemory(pixels);
          return(MagickFalse);
        }
      }
    }

  if (compression == ZipWithPrediction)
  {
     p=pixels;
     while(count > 0)
     {
       length=image->columns;
       while(--length)
       {
         if (packet_size == 2)
           {
             p[2]+=p[0]+((p[1]+p[3]) >> 8);
             p[3]+=p[1];
           }
         else
          *(p+1)+=*p;
         p+=packet_size;
       }
       p+=packet_size;
       count-=row_size;
     }
  }

  status=MagickTrue;
  p=pixels;
  for (y=0; y < (ssize_t) image->rows; y++)
  {
    status=ReadPSDChannelPixels(image,channels,y,type,p,exception);
    if (status == MagickFalse)
      break;

    p+=row_size;
  }

  compact_pixels=(unsigned char *) RelinquishMagickMemory(compact_pixels);
  pixels=(unsigned char *) RelinquishMagickMemory(pixels);
  return(status);
}
#endif

static MagickBooleanType ReadPSDChannel(Image *image,const PSDInfo *psd_info,
  LayerInfo* layer_info,const size_t channel,
  const PSDCompressionType compression,ExceptionInfo *exception)
{
  Image
    *channel_image,
    *mask;

  MagickOffsetType
    offset;

  MagickBooleanType
    status;

  channel_image=image;
  mask=(Image *) NULL;
  if (layer_info->channel_info[channel].type < -1)
  {
    /*
      Ignore mask that is not a user supplied layer mask, if the mask is
      disabled or if the flags have unsupported values.
    */
    if (layer_info->channel_info[channel].type != -2 ||
        (layer_info->mask.flags > 3) || (layer_info->mask.flags & 0x02))
    {
      SeekBlob(image,layer_info->channel_info[channel].size-2,SEEK_CUR);
      return(MagickTrue);
    }
    mask=CloneImage(image,layer_info->mask.page.width,
      layer_info->mask.page.height,MagickFalse,exception);
    mask->matte=MagickFalse;
    channel_image=mask;
  }

  offset=TellBlob(channel_image);
  status=MagickTrue;
  switch(compression)
  {
    case Raw:
      status=ReadPSDChannelRaw(channel_image,psd_info->channels,
        layer_info->channel_info[channel].type,exception);
      break;
    case RLE:
      {
        MagickOffsetType
          *offsets;

        offsets=ReadPSDRLEOffsets(channel_image,psd_info,channel_image->rows);
        if (offsets == (MagickOffsetType *) NULL)
          ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
            image->filename);
        status=ReadPSDChannelRLE(channel_image,psd_info,
          layer_info->channel_info[channel].type,offsets,exception);
        offsets=(MagickOffsetType *) RelinquishMagickMemory(offsets);
      }
      break;
    case ZipWithPrediction:
    case ZipWithoutPrediction:
#ifdef MAGICKCORE_ZLIB_DELEGATE
      status=ReadPSDChannelZip(channel_image,layer_info->channels,
        layer_info->channel_info[channel].type,compression,
        layer_info->channel_info[channel].size-2,exception);
#else
      SeekBlob(image,offset+layer_info->channel_info[channel].size-2,SEEK_SET);
      (void) ThrowMagickException(exception,GetMagickModule(),
          MissingDelegateWarning,"DelegateLibrarySupportNotBuiltIn",
            "'%s' (ZLIB)",image->filename);
#endif
      break;
    default:
      SeekBlob(image,offset+layer_info->channel_info[channel].size-2,SEEK_SET);
      (void) ThrowMagickException(exception,GetMagickModule(),TypeWarning,
        "CompressionNotSupported","'%.20g'",(double) compression);
      break;
  }

  if (status == MagickFalse)
    {
      if (mask != (Image *) NULL)
        DestroyImage(mask);
      SeekBlob(image,offset+layer_info->channel_info[channel].size-2,SEEK_SET);
      ThrowBinaryException(CoderError,"UnableToDecompressImage",
        image->filename);
    }
  if (mask != (Image *) NULL)
  {
    if (status != MagickFalse)
      {
        MagickPixelPacket
          color;

        layer_info->mask.image=CloneImage(image,image->columns,image->rows,
          MagickTrue,exception);
        layer_info->mask.image->matte=MagickFalse;
        GetMagickPixelPacket(layer_info->mask.image,&color);
        color.red=layer_info->mask.background == 0 ? 0 : QuantumRange;
        color.green=color.red;
        color.blue=color.red;
        color.index=color.red;
        SetImageColor(layer_info->mask.image,&color);
        (void) CompositeImage(layer_info->mask.image,OverCompositeOp,mask,
          layer_info->mask.page.x,layer_info->mask.page.y);
      }
    DestroyImage(mask);
  }

  return(status);
}

static MagickBooleanType ReadPSDLayer(Image *image,const PSDInfo *psd_info,
  LayerInfo* layer_info,ExceptionInfo *exception)
{
  char
    message[MaxTextExtent];

  MagickBooleanType
    status;

  PSDCompressionType
    compression;

  ssize_t
    j;

  if (image->debug != MagickFalse)
    (void) LogMagickEvent(CoderEvent,GetMagickModule(),
      "    setting up new layer image");
  (void) SetImageBackgroundColor(layer_info->image);
  layer_info->image->compose=PSDBlendModeToCompositeOperator(
    layer_info->blendkey);
  if (layer_info->visible == MagickFalse)
    {
      layer_info->image->compose=NoCompositeOp;
      (void) SetImageArtifact(layer_info->image,"psd:layer.invisible","true");
    }
  if (psd_info->mode == CMYKMode)
    SetImageColorspace(layer_info->image,CMYKColorspace);
  if ((psd_info->mode == BitmapMode) || (psd_info->mode == GrayscaleMode) ||
     (psd_info->mode == DuotoneMode))
   SetImageColorspace(layer_info->image,GRAYColorspace);
  /*
    Set up some hidden attributes for folks that need them.
  */
  (void) FormatLocaleString(message,MaxTextExtent,"%.20g",
    (double) layer_info->page.x);
  (void) SetImageArtifact(layer_info->image,"psd:layer.x",message);
  (void) FormatLocaleString(message,MaxTextExtent,"%.20g",
    (double) layer_info->page.y);
  (void) SetImageArtifact(layer_info->image,"psd:layer.y",message);
  (void) FormatLocaleString(message,MaxTextExtent,"%.20g",(double)
    layer_info->opacity);
  (void) SetImageArtifact(layer_info->image,"psd:layer.opacity",message);
  (void) SetImageProperty(layer_info->image,"label",(char *) layer_info->name);

  status=MagickTrue;
  for (j=0; j < (ssize_t) layer_info->channels; j++)
  {
    if (image->debug != MagickFalse)
      (void) LogMagickEvent(CoderEvent,GetMagickModule(),
        "    reading data for channel %.20g",(double) j);

    compression=(PSDCompressionType) ReadBlobShort(layer_info->image);
    layer_info->image->compression=ConvertPSDCompression(compression);
    if (layer_info->channel_info[j].type == -1)
      layer_info->image->matte=MagickTrue;

    status=ReadPSDChannel(layer_info->image,psd_info,layer_info,j,
      compression,exception);
    InheritException(exception,&layer_info->image->exception);

    if (status == MagickFalse)
      break;
  }

  if (status != MagickFalse)
    status=CorrectPSDOpacity(layer_info,exception);

  if ((status != MagickFalse) &&
      (layer_info->image->colorspace == CMYKColorspace))
    status=NegateImage(layer_info->image,MagickFalse);

  if (status != MagickFalse && layer_info->mask.image != (Image *) NULL)
    {
      status=CompositeImage(layer_info->image,CopyOpacityCompositeOp,
        layer_info->mask.image,0,0);
      layer_info->mask.image=DestroyImage(layer_info->mask.image);
    }

  return(status);
}

ModuleExport MagickBooleanType ReadPSDLayers(Image *image,
  const ImageInfo *image_info,const PSDInfo *psd_info,
  const MagickBooleanType skip_layers,ExceptionInfo *exception)
{
  char
    type[4];

  LayerInfo
    *layer_info;

  MagickSizeType
    size;

  MagickBooleanType
    status;

  register ssize_t
    i;

  ssize_t
    count,
    j,
    number_layers;

  size=GetPSDSize(psd_info,image);
  if (size == 0)
    {
      /*
        Skip layers & masks.
      */
      (void) ReadBlobLong(image);
      count=ReadBlob(image,4,(unsigned char *) type);
      ReversePSDString(image,type,4);
      status=MagickFalse;
      if ((count == 0) || (LocaleNCompare(type,"8BIM",4) != 0))
        return(MagickTrue);
      else
        {
          count=ReadBlob(image,4,(unsigned char *) type);
          ReversePSDString(image,type,4);
          if ((count != 0) && (LocaleNCompare(type,"Lr16",4) == 0))
            size=GetPSDSize(psd_info,image);
          else
            return(MagickTrue);
        }
    }
  status=MagickTrue;
  if (size != 0)
    {
      layer_info=(LayerInfo *) NULL;
      number_layers=(short) ReadBlobShort(image);

      if (number_layers < 0)
        {
          /*
            The first alpha channel in the merged result contains the
            transparency data for the merged result.
          */
          number_layers=MagickAbsoluteValue(number_layers);
          if (image->debug != MagickFalse)
            (void) LogMagickEvent(CoderEvent,GetMagickModule(),
              "  negative layer count corrected for");
          image->matte=MagickTrue;
        }

      /*
        We only need to know if the image has an alpha channel
      */
      if (skip_layers != MagickFalse)
        return(MagickTrue);

      if (image->debug != MagickFalse)
        (void) LogMagickEvent(CoderEvent,GetMagickModule(),
          "  image contains %.20g layers",(double) number_layers);

      if (number_layers == 0)
        ThrowBinaryException(CorruptImageError,"InvalidNumberOfLayers",
          image->filename);

      layer_info=(LayerInfo *) AcquireQuantumMemory((size_t) number_layers,
        sizeof(*layer_info));
      if (layer_info == (LayerInfo *) NULL)
        {
          if (image->debug != MagickFalse)
            (void) LogMagickEvent(CoderEvent,GetMagickModule(),
              "  allocation of LayerInfo failed");
          ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
            image->filename);
        }
      (void) ResetMagickMemory(layer_info,0,(size_t) number_layers*
        sizeof(*layer_info));

      for (i=0; i < number_layers; i++)
      {
        ssize_t
          x,
          y;

        if (image->debug != MagickFalse)
          (void) LogMagickEvent(CoderEvent,GetMagickModule(),
            "  reading layer #%.20g",(double) i+1);
        layer_info[i].page.y=(int) ReadBlobLong(image);
        layer_info[i].page.x=(int) ReadBlobLong(image);
        y=(int) ReadBlobLong(image);
        x=(int) ReadBlobLong(image);
        layer_info[i].page.width=(size_t) (x-layer_info[i].page.x);
        layer_info[i].page.height=(size_t) (y-layer_info[i].page.y);
        layer_info[i].channels=ReadBlobShort(image);
        if (layer_info[i].channels > MaxPSDChannels)
          {
            layer_info=DestroyLayerInfo(layer_info,number_layers);
            ThrowBinaryException(CorruptImageError,"MaximumChannelsExceeded",
              image->filename);
          }
        if (image->debug != MagickFalse)
          (void) LogMagickEvent(CoderEvent,GetMagickModule(),
            "    offset(%.20g,%.20g), size(%.20g,%.20g), channels=%.20g",
            (double) layer_info[i].page.x,(double) layer_info[i].page.y,
            (double) layer_info[i].page.height,(double)
            layer_info[i].page.width,(double) layer_info[i].channels);
        for (j=0; j < (ssize_t) layer_info[i].channels; j++)
        {
          layer_info[i].channel_info[j].type=(short) ReadBlobShort(image);
          layer_info[i].channel_info[j].size=(size_t) GetPSDSize(psd_info,
            image);
          if (image->debug != MagickFalse)
            (void) LogMagickEvent(CoderEvent,GetMagickModule(),
              "    channel[%.20g]: type=%.20g, size=%.20g",(double) j,
              (double) layer_info[i].channel_info[j].type,
              (double) layer_info[i].channel_info[j].size);
        }
        count=ReadBlob(image,4,(unsigned char *) type);
        ReversePSDString(image,type,4);
        if ((count == 0) || (LocaleNCompare(type,"8BIM",4) != 0))
          {
            if (image->debug != MagickFalse)
              (void) LogMagickEvent(CoderEvent,GetMagickModule(),
                "  layer type was %.4s instead of 8BIM", type);
            layer_info=DestroyLayerInfo(layer_info,number_layers);
            ThrowBinaryException(CorruptImageError,"ImproperImageHeader",
              image->filename);
          }
        (void) ReadBlob(image,4,(unsigned char *) layer_info[i].blendkey);
        ReversePSDString(image,layer_info[i].blendkey,4);
        layer_info[i].opacity=(Quantum) (QuantumRange-ScaleCharToQuantum(
          (unsigned char) ReadBlobByte(image)));
        layer_info[i].clipping=(unsigned char) ReadBlobByte(image);
        layer_info[i].flags=(unsigned char) ReadBlobByte(image);
        layer_info[i].visible=!(layer_info[i].flags & 0x02);
        if (image->debug != MagickFalse)
          (void) LogMagickEvent(CoderEvent,GetMagickModule(),
            "   blend=%.4s, opacity=%.20g, clipping=%s, flags=%d, visible=%s",
            layer_info[i].blendkey,(double) layer_info[i].opacity,
            layer_info[i].clipping ? "true" : "false",layer_info[i].flags,
            layer_info[i].visible ? "true" : "false");
        (void) ReadBlobByte(image);  /* filler */

        size=ReadBlobLong(image);
        if (size != 0)
          {
            MagickSizeType
              combined_length,
              length;

            if (image->debug != MagickFalse)
              (void) LogMagickEvent(CoderEvent,GetMagickModule(),
                "    layer contains additional info");
            length=ReadBlobLong(image);
            combined_length=length+4;
            if (length != 0)
              {
                /*
                  Layer mask info.
                */
                layer_info[i].mask.page.y=(int) ReadBlobLong(image);
                layer_info[i].mask.page.x=(int) ReadBlobLong(image);
                layer_info[i].mask.page.height=(size_t) (ReadBlobLong(image)-
                  layer_info[i].mask.page.y);
                layer_info[i].mask.page.width=(size_t) (ReadBlobLong(image)-
                  layer_info[i].mask.page.x);
                layer_info[i].mask.background=(unsigned char) ReadBlobByte(
                  image);
                layer_info[i].mask.flags=(unsigned char) ReadBlobByte(image);
                if (!(layer_info[i].mask.flags & 0x01))
                  {
                    layer_info[i].mask.page.y=layer_info[i].mask.page.y-
                      layer_info[i].page.y;
                    layer_info[i].mask.page.x=layer_info[i].mask.page.x-
                      layer_info[i].page.x;
                  }
                if (image->debug != MagickFalse)
                  (void) LogMagickEvent(CoderEvent,GetMagickModule(),
                    "      layer mask: offset(%.20g,%.20g), size(%.20g,%.20g), length=%.20g",
                    (double) layer_info[i].mask.page.x,(double)
                    layer_info[i].mask.page.y,(double) layer_info[i].mask.page.width,
                    (double) layer_info[i].mask.page.height,(double)
                    ((MagickOffsetType) length)-18);
                /*
                  Skip over the rest of the layer mask information.
                */
                if (DiscardBlobBytes(image,(MagickSizeType) (length-18)) == MagickFalse)
                  {
                    layer_info=DestroyLayerInfo(layer_info,number_layers);
                    ThrowBinaryException(CorruptImageError,"UnexpectedEndOfFile",
                      image->filename);
                  }
              }
            length=ReadBlobLong(image);
            combined_length+=length+4;
            if (length != 0)
              {
                /*
                  Layer blending ranges info.
                */
                if (image->debug != MagickFalse)
                  (void) LogMagickEvent(CoderEvent,GetMagickModule(),
                    "      layer blending ranges: length=%.20g",(double)
                    ((MagickOffsetType) length));
                /*
                  We read it, but don't use it...
                */
                for (j=0; j < (ssize_t) (length); j+=8)
                {
                  size_t blend_source=ReadBlobLong(image);
                  size_t blend_dest=ReadBlobLong(image);
                  if (image->debug != MagickFalse)
                    (void) LogMagickEvent(CoderEvent,GetMagickModule(),
                      "        source(%x), dest(%x)",(unsigned int)
                      blend_source,(unsigned int) blend_dest);
                }
              }
            /*
              Layer name.
            */
            length=(size_t) ReadBlobByte(image);
            combined_length+=length+1;
            if (length > 0)
              (void) ReadBlob(image,(size_t) length++,layer_info[i].name);
            layer_info[i].name[length]='\0';
            if (image->debug != MagickFalse)
              (void) LogMagickEvent(CoderEvent,GetMagickModule(),
                "      layer name: %s",layer_info[i].name);
            /*
               Skip the rest of the variable data until we support it.
             */
             if (image->debug != MagickFalse)
               (void) LogMagickEvent(CoderEvent,GetMagickModule(),
                 "      unsupported data: length=%.20g",(double)
                 ((MagickOffsetType) (size-combined_length)));
             if (DiscardBlobBytes(image,(MagickSizeType) (size-combined_length)) == MagickFalse)
               {
                 layer_info=DestroyLayerInfo(layer_info,number_layers);
                 ThrowBinaryException(CorruptImageError,
                   "UnexpectedEndOfFile",image->filename);
               }
          }
      }

      for (i=0; i < number_layers; i++)
      {
        if ((layer_info[i].page.width == 0) ||
              (layer_info[i].page.height == 0))
          {
            if (image->debug != MagickFalse)
              (void) LogMagickEvent(CoderEvent,GetMagickModule(),
                "      layer data is empty");
            continue;
          }

        /*
          Allocate layered image.
        */
        layer_info[i].image=CloneImage(image,layer_info[i].page.width,
          layer_info[i].page.height,MagickFalse,exception);
        if (layer_info[i].image == (Image *) NULL)
          {
            layer_info=DestroyLayerInfo(layer_info,number_layers);
            if (image->debug != MagickFalse)
              (void) LogMagickEvent(CoderEvent,GetMagickModule(),
                "  allocation of image for layer %.20g failed",(double) i);
            ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
              image->filename);
          }
      }

      if (image_info->ping == MagickFalse)
        {
          for (i=0; i < number_layers; i++)
          {
            if (layer_info[i].image == (Image *) NULL)
              {
                for (j=0; j < layer_info[i].channels; j++)
                {
                  if (DiscardBlobBytes(image,(MagickSizeType)
                      layer_info[i].channel_info[j].size) == MagickFalse)
                    {
                      layer_info=DestroyLayerInfo(layer_info,number_layers);
                      ThrowBinaryException(CorruptImageError,
                        "UnexpectedEndOfFile",image->filename);
                    }
                }
                continue;
              }

            if (image->debug != MagickFalse)
              (void) LogMagickEvent(CoderEvent,GetMagickModule(),
                "  reading data for layer %.20g",(double) i);
            status=ReadPSDLayer(image,psd_info,&layer_info[i],exception);
            if (status == MagickFalse)
              break;

            status=SetImageProgress(image,LoadImagesTag,i,(MagickSizeType)
              number_layers);
            if (status == MagickFalse)
              break;
          }
        }

      if (status != MagickFalse)
      {
        for (i=0; i < number_layers; i++)
        {
          if (layer_info[i].image == (Image *) NULL)
          {
            for (j=i; j < number_layers - 1; j++)
              layer_info[j] = layer_info[j+1];
            number_layers--;
            i--;
          }
        }

        if (number_layers > 0)
          {
            for (i=0; i < number_layers; i++)
            {
              if (i > 0)
                layer_info[i].image->previous=layer_info[i-1].image;
              if (i < (number_layers-1))
                layer_info[i].image->next=layer_info[i+1].image;
              layer_info[i].image->page=layer_info[i].page;
            }
            image->next=layer_info[0].image;
            layer_info[0].image->previous=image;
          }
        layer_info=(LayerInfo *) RelinquishMagickMemory(layer_info);
      }
      else
        layer_info=DestroyLayerInfo(layer_info,number_layers);
    }

  return(status);
}

static MagickBooleanType ReadPSDMergedImage(const ImageInfo *image_info,Image* image,
  const PSDInfo* psd_info,ExceptionInfo *exception)
{
  MagickOffsetType
    *offsets;

  MagickBooleanType
    status;

  PSDCompressionType
    compression;

  register ssize_t
    i;

  compression=(PSDCompressionType) ReadBlobMSBShort(image);
  image->compression=ConvertPSDCompression(compression);

  if (compression != Raw && compression != RLE)
    {
      (void) ThrowMagickException(exception,GetMagickModule(),
        TypeWarning,"CompressionNotSupported","'%.20g'",(double) compression);
      return(MagickFalse);
    }

  offsets=(MagickOffsetType *) NULL;
  if (compression == RLE)
  {
    offsets=ReadPSDRLEOffsets(image,psd_info,image->rows*psd_info->channels);
    if (offsets == (MagickOffsetType *) NULL)
      ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
        image->filename);
  }

  status=MagickTrue;
  for (i=0; i < (ssize_t) psd_info->channels; i++)
  {
    if (compression == RLE)
      status=ReadPSDChannelRLE(image,psd_info,i,offsets+(i*image->rows),
        exception);
    else
      status=ReadPSDChannelRaw(image,psd_info->channels,i,exception);

    if (status != MagickFalse)
      status=SetImageProgress(image,LoadImagesTag,i,psd_info->channels);

    if (status == MagickFalse)
      break;
  }

  if ((status != MagickFalse) && (image->colorspace == CMYKColorspace))
    status=NegateImage(image,MagickFalse);

  if (status != MagickFalse)
    status=CorrectPSDAlphaBlend(image_info,image,exception);

  if (offsets != (MagickOffsetType *) NULL)
    offsets=(MagickOffsetType *) RelinquishMagickMemory(offsets);

  return(status);
}

static Image *ReadPSDImage(const ImageInfo *image_info,ExceptionInfo *exception)
{
  Image
    *image;

  MagickBooleanType
    has_merged_image,
    skip_layers;

  MagickOffsetType
    offset;

  MagickSizeType
    length;

  MagickBooleanType
    status;

  PSDInfo
    psd_info;

  register ssize_t
    i;

  ssize_t
    count;

  unsigned char
    *data;

  /*
    Open image file.
  */
  assert(image_info != (const ImageInfo *) NULL);
  assert(image_info->signature == MagickSignature);
  if (image_info->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
      image_info->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);

  image=AcquireImage(image_info);
  status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
  if (status == MagickFalse)
    {
      image=DestroyImageList(image);
      return((Image *) NULL);
    }
  /*
    Read image header.
  */
  image->endian=MSBEndian;
  count=ReadBlob(image,4,(unsigned char *) psd_info.signature);
  psd_info.version=ReadBlobMSBShort(image);
  if ((count == 0) || (LocaleNCompare(psd_info.signature,"8BPS",4) != 0) ||
      ((psd_info.version != 1) && (psd_info.version != 2)))
    ThrowReaderException(CorruptImageError,"ImproperImageHeader");
  (void) ReadBlob(image,6,psd_info.reserved);
  psd_info.channels=ReadBlobMSBShort(image);
  if (psd_info.channels > MaxPSDChannels)
    ThrowReaderException(CorruptImageError,"MaximumChannelsExceeded");
  psd_info.rows=ReadBlobMSBLong(image);
  psd_info.columns=ReadBlobMSBLong(image);
  if ((psd_info.version == 1) && ((psd_info.rows > 30000) ||
      (psd_info.columns > 30000)))
    ThrowReaderException(CorruptImageError,"ImproperImageHeader");
  psd_info.depth=ReadBlobMSBShort(image);
  if ((psd_info.depth != 1) && (psd_info.depth != 8) && (psd_info.depth != 16))
    ThrowReaderException(CorruptImageError,"ImproperImageHeader");
  psd_info.mode=ReadBlobMSBShort(image);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(CoderEvent,GetMagickModule(),
      "  Image is %.20g x %.20g with channels=%.20g, depth=%.20g, mode=%s",
      (double) psd_info.columns,(double) psd_info.rows,(double)
      psd_info.channels,(double) psd_info.depth,ModeToString((PSDImageType)
      psd_info.mode));
  /*
    Initialize image.
  */
  image->depth=psd_info.depth;
  image->columns=psd_info.columns;
  image->rows=psd_info.rows;
  status=SetImageExtent(image,image->columns,image->rows);
  if (status == MagickFalse)
    {
      InheritException(exception,&image->exception);
      return(DestroyImageList(image));
    }
  if (SetImageBackgroundColor(image) == MagickFalse)
    {
      InheritException(exception,&image->exception);
      image=DestroyImageList(image);
      return((Image *) NULL);
    }
  if (psd_info.mode == LabMode)
    SetImageColorspace(image,LabColorspace);
  if (psd_info.mode == CMYKMode)
  {
    SetImageColorspace(image,CMYKColorspace);
    image->matte=psd_info.channels > 4 ? MagickTrue : MagickFalse;
  }
  else if ((psd_info.mode == BitmapMode) || (psd_info.mode == GrayscaleMode) ||
      (psd_info.mode == DuotoneMode))
    {
      status=AcquireImageColormap(image,psd_info.depth != 16 ? 256 : 65536);
      if (status == MagickFalse)
        ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
      if (image->debug != MagickFalse)
        (void) LogMagickEvent(CoderEvent,GetMagickModule(),
          "  Image colormap allocated");
      SetImageColorspace(image,GRAYColorspace);
      image->matte=psd_info.channels > 1 ? MagickTrue : MagickFalse;
    }
  else
    image->matte=psd_info.channels > 3 ? MagickTrue : MagickFalse;
  /*
    Read PSD raster colormap only present for indexed and duotone images.
  */
  length=ReadBlobMSBLong(image);
  if (length != 0)
    {
      if (image->debug != MagickFalse)
        (void) LogMagickEvent(CoderEvent,GetMagickModule(),
          "  reading colormap");
      if (psd_info.mode == DuotoneMode)
        {
          /*
            Duotone image data;  the format of this data is undocumented.
          */
          data=(unsigned char *) AcquireQuantumMemory((size_t) length,
            sizeof(*data));
          if (data == (unsigned char *) NULL)
            ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
          (void) ReadBlob(image,(size_t) length,data);
          data=(unsigned char *) RelinquishMagickMemory(data);
        }
      else
        {
          size_t
            number_colors;

          /*
            Read PSD raster colormap.
          */
          number_colors=length/3;
          if (number_colors > 65536)
            ThrowReaderException(CorruptImageError,"ImproperImageHeader");
          if (AcquireImageColormap(image,number_colors) == MagickFalse)
            ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
          for (i=0; i < (ssize_t) image->colors; i++)
            image->colormap[i].red=ScaleCharToQuantum((unsigned char)
              ReadBlobByte(image));
          for (i=0; i < (ssize_t) image->colors; i++)
            image->colormap[i].green=ScaleCharToQuantum((unsigned char)
              ReadBlobByte(image));
          for (i=0; i < (ssize_t) image->colors; i++)
            image->colormap[i].blue=ScaleCharToQuantum((unsigned char)
              ReadBlobByte(image));
          image->matte=MagickFalse;
        }
    }
  has_merged_image=MagickTrue;
  length=ReadBlobMSBLong(image);
  if (length != 0)
    {
      unsigned char
        *blocks;

      /*
        Image resources block.
      */
      if (image->debug != MagickFalse)
        (void) LogMagickEvent(CoderEvent,GetMagickModule(),
          "  reading image resource blocks - %.20g bytes",(double)
          ((MagickOffsetType) length));
      blocks=(unsigned char *) AcquireQuantumMemory((size_t) length,
        sizeof(*blocks));
      if (blocks == (unsigned char *) NULL)
        ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
      count=ReadBlob(image,(size_t) length,blocks);
      if ((count != (ssize_t) length) ||
          (LocaleNCompare((char *) blocks,"8BIM",4) != 0))
        {
          blocks=(unsigned char *) RelinquishMagickMemory(blocks);
          ThrowReaderException(CorruptImageError,"ImproperImageHeader");
        }
      ParseImageResourceBlocks(image,blocks,(size_t) length,&has_merged_image);
      blocks=(unsigned char *) RelinquishMagickMemory(blocks);
    }
  /*
    Layer and mask block.
  */
  length=GetPSDSize(&psd_info,image);
  if (length == 8)
    {
      length=ReadBlobMSBLong(image);
      length=ReadBlobMSBLong(image);
    }
  offset=TellBlob(image);
  skip_layers=MagickFalse;
  if ((image_info->number_scenes == 1) && (image_info->scene == 0) &&
      (has_merged_image != MagickFalse))
    {
      if (image->debug != MagickFalse)
        (void) LogMagickEvent(CoderEvent,GetMagickModule(),
          "  read composite only");
      skip_layers=MagickTrue;
    }
  if (length == 0)
    {
      if (image->debug != MagickFalse)
        (void) LogMagickEvent(CoderEvent,GetMagickModule(),
          "  image has no layers");
    }
  else
    {
      if (ReadPSDLayers(image,image_info,&psd_info,skip_layers,exception) !=
          MagickTrue)
        {
          (void) CloseBlob(image);
          image=DestroyImageList(image);
          return((Image *) NULL);
        }
      /*
         Skip the rest of the layer and mask information.
      */
      SeekBlob(image,offset+length,SEEK_SET);
    }
  /*
    If we are only "pinging" the image, then we're done - so return.
  */
  if (image_info->ping != MagickFalse)
    {
      (void) CloseBlob(image);
      return(GetFirstImageInList(image));
    }
  /*
    Read the precombined layer, present for PSD < 4 compatibility.
  */
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(CoderEvent,GetMagickModule(),
      "  reading the precombined layer");
  if (has_merged_image != MagickFalse || GetImageListLength(image) == 1)
    has_merged_image=(MagickBooleanType) ReadPSDMergedImage(image_info,image,
      &psd_info,exception);
  if ((has_merged_image == MagickFalse) && (GetImageListLength(image) == 1) &&
      (length != 0))
    {
      SeekBlob(image,offset,SEEK_SET);
      status=ReadPSDLayers(image,image_info,&psd_info,MagickFalse,exception);
      if (status != MagickTrue)
        {
          (void) CloseBlob(image);
          image=DestroyImageList(image);
          return((Image *) NULL);
        }
    }
  if ((has_merged_image == MagickFalse) && (GetImageListLength(image) > 1))
    {
      Image
        *merged;

      SetImageAlphaChannel(image,TransparentAlphaChannel);
      image->background_color.opacity=TransparentOpacity;
      merged=MergeImageLayers(image,FlattenLayer,exception);
      ReplaceImageInList(&image,merged);
    }
  (void) CloseBlob(image);
  return(GetFirstImageInList(image));
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   R e g i s t e r P S D I m a g e                                           %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  RegisterPSDImage() adds properties for the PSD image format to
%  the list of supported formats.  The properties include the image format
%  tag, a method to read and/or write the format, whether the format
%  supports the saving of more than one frame to the same file or blob,
%  whether the format supports native in-memory I/O, and a brief
%  description of the format.
%
%  The format of the RegisterPSDImage method is:
%
%      size_t RegisterPSDImage(void)
%
*/
ModuleExport size_t RegisterPSDImage(void)
{
  MagickInfo
    *entry;

  entry=SetMagickInfo("PSB");
  entry->decoder=(DecodeImageHandler *) ReadPSDImage;
  entry->encoder=(EncodeImageHandler *) WritePSDImage;
  entry->magick=(IsImageFormatHandler *) IsPSD;
  entry->seekable_stream=MagickTrue;
  entry->description=ConstantString("Adobe Large Document Format");
  entry->module=ConstantString("PSD");
  (void) RegisterMagickInfo(entry);
  entry=SetMagickInfo("PSD");
  entry->decoder=(DecodeImageHandler *) ReadPSDImage;
  entry->encoder=(EncodeImageHandler *) WritePSDImage;
  entry->magick=(IsImageFormatHandler *) IsPSD;
  entry->seekable_stream=MagickTrue;
  entry->description=ConstantString("Adobe Photoshop bitmap");
  entry->module=ConstantString("PSD");
  (void) RegisterMagickInfo(entry);
  return(MagickImageCoderSignature);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   U n r e g i s t e r P S D I m a g e                                       %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  UnregisterPSDImage() removes format registrations made by the
%  PSD module from the list of supported formats.
%
%  The format of the UnregisterPSDImage method is:
%
%      UnregisterPSDImage(void)
%
*/
ModuleExport void UnregisterPSDImage(void)
{
  (void) UnregisterMagickInfo("PSB");
  (void) UnregisterMagickInfo("PSD");
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   W r i t e P S D I m a g e                                                 %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  WritePSDImage() writes an image in the Adobe Photoshop encoded image format.
%
%  The format of the WritePSDImage method is:
%
%      MagickBooleanType WritePSDImage(const ImageInfo *image_info,Image *image)
%
%  A description of each parameter follows.
%
%    o image_info: the image info.
%
%    o image:  The image.
%
*/

static inline ssize_t SetPSDOffset(const PSDInfo *psd_info,Image *image,
  const size_t offset)
{
  if (psd_info->version == 1)
    return(WriteBlobMSBShort(image,(unsigned short) offset));
  return(WriteBlobMSBLong(image,(unsigned short) offset));
}

static inline ssize_t SetPSDSize(const PSDInfo *psd_info,Image *image,
  const MagickSizeType size)
{
  if (psd_info->version == 1)
    return(WriteBlobMSBLong(image,(unsigned int) size));
  return(WriteBlobMSBLongLong(image,size));
}

static size_t PSDPackbitsEncodeImage(Image *image,const size_t length,
  const unsigned char *pixels,unsigned char *compact_pixels)
{
  int
    count;

  register ssize_t
    i,
    j;

  register unsigned char
    *q;

  unsigned char
    *packbits;

  /*
    Compress pixels with Packbits encoding.
  */
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(pixels != (unsigned char *) NULL);
  packbits=(unsigned char *) AcquireQuantumMemory(128UL,sizeof(*packbits));
  if (packbits == (unsigned char *) NULL)
    ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
      image->filename);
  q=compact_pixels;
  for (i=(ssize_t) length; i != 0; )
  {
    switch (i)
    {
      case 1:
      {
        i--;
        *q++=(unsigned char) 0;
        *q++=(*pixels);
        break;
      }
      case 2:
      {
        i-=2;
        *q++=(unsigned char) 1;
        *q++=(*pixels);
        *q++=pixels[1];
        break;
      }
      case 3:
      {
        i-=3;
        if ((*pixels == *(pixels+1)) && (*(pixels+1) == *(pixels+2)))
          {
            *q++=(unsigned char) ((256-3)+1);
            *q++=(*pixels);
            break;
          }
        *q++=(unsigned char) 2;
        *q++=(*pixels);
        *q++=pixels[1];
        *q++=pixels[2];
        break;
      }
      default:
      {
        if ((*pixels == *(pixels+1)) && (*(pixels+1) == *(pixels+2)))
          {
            /*
              Packed run.
            */
            count=3;
            while (((ssize_t) count < i) && (*pixels == *(pixels+count)))
            {
              count++;
              if (count >= 127)
                break;
            }
            i-=count;
            *q++=(unsigned char) ((256-count)+1);
            *q++=(*pixels);
            pixels+=count;
            break;
          }
        /*
          Literal run.
        */
        count=0;
        while ((*(pixels+count) != *(pixels+count+1)) ||
               (*(pixels+count+1) != *(pixels+count+2)))
        {
          packbits[count+1]=pixels[count];
          count++;
          if (((ssize_t) count >= (i-3)) || (count >= 127))
            break;
        }
        i-=count;
        *packbits=(unsigned char) (count-1);
        for (j=0; j <= (ssize_t) count; j++)
          *q++=packbits[j];
        pixels+=count;
        break;
      }
    }
  }
  *q++=(unsigned char) 128;  /* EOD marker */
  packbits=(unsigned char *) RelinquishMagickMemory(packbits);
  return((size_t) (q-compact_pixels));
}

static void WritePackbitsLength(const PSDInfo *psd_info,
  const ImageInfo *image_info,Image *image,Image *next_image,
  unsigned char *compact_pixels,const QuantumType quantum_type)
{
  QuantumInfo
    *quantum_info;

  register const PixelPacket
    *p;

  size_t
    length,
    packet_size;

  ssize_t
    y;

  unsigned char
    *pixels;

  if (next_image->depth > 8)
    next_image->depth=16;
  packet_size=next_image->depth > 8UL ? 2UL : 1UL;
  (void) packet_size;
  quantum_info=AcquireQuantumInfo(image_info,image);
  pixels=GetQuantumPixels(quantum_info);
  for (y=0; y < (ssize_t) next_image->rows; y++)
  {
    p=GetVirtualPixels(next_image,0,y,next_image->columns,1,&image->exception);
    if (p == (const PixelPacket *) NULL)
      break;
    length=ExportQuantumPixels(next_image,(CacheView *) NULL,quantum_info,
      quantum_type,pixels,&image->exception);
    length=PSDPackbitsEncodeImage(image,length,pixels,compact_pixels);
    (void) SetPSDOffset(psd_info,image,length);
  }
  quantum_info=DestroyQuantumInfo(quantum_info);
}

static void WriteOneChannel(const PSDInfo *psd_info,const ImageInfo *image_info,
  Image *image,Image *next_image,unsigned char *compact_pixels,
  const QuantumType quantum_type,const MagickBooleanType compression_flag)
{
  int
    y;

  MagickBooleanType
    monochrome;

  QuantumInfo
    *quantum_info;

  register const PixelPacket
    *p;

  register ssize_t
    i;

  size_t
    length,
    packet_size;

  unsigned char
    *pixels;

  (void) psd_info;
  if ((compression_flag != MagickFalse) &&
      (next_image->compression != RLECompression))
    (void) WriteBlobMSBShort(image,0);
  if (next_image->depth > 8)
    next_image->depth=16;
  monochrome=IsMonochromeImage(image,&image->exception) && (image->depth == 1)
    ? MagickTrue : MagickFalse;
  packet_size=next_image->depth > 8UL ? 2UL : 1UL;
  (void) packet_size;
  quantum_info=AcquireQuantumInfo(image_info,image);
  pixels=GetQuantumPixels(quantum_info);
  for (y=0; y < (ssize_t) next_image->rows; y++)
  {
    p=GetVirtualPixels(next_image,0,y,next_image->columns,1,&image->exception);
    if (p == (const PixelPacket *) NULL)
      break;
    length=ExportQuantumPixels(next_image,(CacheView *) NULL,quantum_info,
      quantum_type,pixels,&image->exception);
    if (monochrome != MagickFalse)
      for (i=0; i < (ssize_t) length; i++)
        pixels[i]=(~pixels[i]);
    if (next_image->compression != RLECompression)
      (void) WriteBlob(image,length,pixels);
    else
      {
        length=PSDPackbitsEncodeImage(image,length,pixels,compact_pixels);
        (void) WriteBlob(image,length,compact_pixels);
      }
  }
  quantum_info=DestroyQuantumInfo(quantum_info);
}

static MagickBooleanType WriteImageChannels(const PSDInfo *psd_info,
  const ImageInfo *image_info,Image *image,Image *next_image,
  const MagickBooleanType separate)
{
  size_t
    channels,
    packet_size;

  unsigned char
    *compact_pixels;

  /*
    Write uncompressed pixels as separate planes.
  */
  channels=1;
  packet_size=next_image->depth > 8UL ? 2UL : 1UL;
  compact_pixels=(unsigned char *) NULL;
  if (next_image->compression == RLECompression)
    {
      compact_pixels=(unsigned char *) AcquireQuantumMemory(2*channels*
        next_image->columns,packet_size*sizeof(*compact_pixels));
      if (compact_pixels == (unsigned char *) NULL)
        ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
    }
  if (IsGrayImage(next_image,&next_image->exception) != MagickFalse)
    {
      if (next_image->compression == RLECompression)
        {
          /*
            Packbits compression.
          */
          (void) WriteBlobMSBShort(image,1);
          WritePackbitsLength(psd_info,image_info,image,next_image,
            compact_pixels,GrayQuantum);
          if (next_image->matte != MagickFalse)
            WritePackbitsLength(psd_info,image_info,image,next_image,
              compact_pixels,AlphaQuantum);
        }
      WriteOneChannel(psd_info,image_info,image,next_image,compact_pixels,
        GrayQuantum,MagickTrue);
      if (next_image->matte != MagickFalse)
        WriteOneChannel(psd_info,image_info,image,next_image,compact_pixels,
          AlphaQuantum,separate);
      (void) SetImageProgress(image,SaveImagesTag,0,1);
    }
  else
    if (next_image->storage_class == PseudoClass)
      {
        if (next_image->compression == RLECompression)
          {
            /*
              Packbits compression.
            */
            (void) WriteBlobMSBShort(image,1);
            WritePackbitsLength(psd_info,image_info,image,next_image,
              compact_pixels,IndexQuantum);
            if (next_image->matte != MagickFalse)
              WritePackbitsLength(psd_info,image_info,image,next_image,
                compact_pixels,AlphaQuantum);
          }
        WriteOneChannel(psd_info,image_info,image,next_image,compact_pixels,
          IndexQuantum,MagickTrue);
        if (next_image->matte != MagickFalse)
          WriteOneChannel(psd_info,image_info,image,next_image,compact_pixels,
            AlphaQuantum,separate);
        (void) SetImageProgress(image,SaveImagesTag,0,1);
      }
    else
      {
        if (next_image->colorspace == CMYKColorspace)
          (void) NegateImage(next_image,MagickFalse);
        if (next_image->compression == RLECompression)
          {
            /*
              Packbits compression.
            */
            (void) WriteBlobMSBShort(image,1);
            WritePackbitsLength(psd_info,image_info,image,next_image,
              compact_pixels,RedQuantum);
            WritePackbitsLength(psd_info,image_info,image,next_image,
              compact_pixels,GreenQuantum);
            WritePackbitsLength(psd_info,image_info,image,next_image,
              compact_pixels,BlueQuantum);
            if (next_image->colorspace == CMYKColorspace)
              WritePackbitsLength(psd_info,image_info,image,next_image,
                compact_pixels,BlackQuantum);
            if (next_image->matte != MagickFalse)
              WritePackbitsLength(psd_info,image_info,image,next_image,
                compact_pixels,AlphaQuantum);
          }
        (void) SetImageProgress(image,SaveImagesTag,0,6);
        WriteOneChannel(psd_info,image_info,image,next_image,compact_pixels,
          RedQuantum,MagickTrue);
        (void) SetImageProgress(image,SaveImagesTag,1,6);
        WriteOneChannel(psd_info,image_info,image,next_image,compact_pixels,
          GreenQuantum,separate);
        (void) SetImageProgress(image,SaveImagesTag,2,6);
        WriteOneChannel(psd_info,image_info,image,next_image,compact_pixels,
          BlueQuantum,separate);
        (void) SetImageProgress(image,SaveImagesTag,3,6);
        if (next_image->colorspace == CMYKColorspace)
          WriteOneChannel(psd_info,image_info,image,next_image,compact_pixels,
            BlackQuantum,separate);
        (void) SetImageProgress(image,SaveImagesTag,4,6);
        if (next_image->matte != MagickFalse)
          WriteOneChannel(psd_info,image_info,image,next_image,compact_pixels,
            AlphaQuantum,separate);
        (void) SetImageProgress(image,SaveImagesTag,5,6);
        if (next_image->colorspace == CMYKColorspace)
          (void) NegateImage(next_image,MagickFalse);
      }
  if (next_image->compression == RLECompression)
    compact_pixels=(unsigned char *) RelinquishMagickMemory(compact_pixels);
  return(MagickTrue);
}

static void WritePascalString(Image* inImage,const char *inString,int inPad)
{
  size_t
    length;

  register ssize_t
    i;

  /*
    Max length is 255.
  */
  length=(strlen(inString) > 255UL ) ? 255UL : strlen(inString);
  if (length ==  0)
    (void) WriteBlobByte(inImage,0);
  else
    {
      (void) WriteBlobByte(inImage,(unsigned char) length);
      (void) WriteBlob(inImage, length, (const unsigned char *) inString);
    }
  length++;
  if ((length % inPad) == 0)
    return;
  for (i=0; i < (ssize_t) (inPad-(length % inPad)); i++)
    (void) WriteBlobByte(inImage,0);
}

static void WriteResolutionResourceBlock(Image *image)
{
  double
    x_resolution,
    y_resolution;

  unsigned short
    units;

  if (image->units == PixelsPerCentimeterResolution)
    {
      x_resolution=2.54*65536.0*image->x_resolution+0.5;
      y_resolution=2.54*65536.0*image->y_resolution+0.5;
      units=2;
    }
  else
    {
      x_resolution=65536.0*image->x_resolution+0.5;
      y_resolution=65536.0*image->y_resolution+0.5;
      units=1;
    }
  (void) WriteBlob(image,4,(const unsigned char *) "8BIM");
  (void) WriteBlobMSBShort(image,0x03ED);
  (void) WriteBlobMSBShort(image,0);
  (void) WriteBlobMSBLong(image,16); /* resource size */
  (void) WriteBlobMSBLong(image,(unsigned int) (x_resolution+0.5));
  (void) WriteBlobMSBShort(image,units); /* horizontal resolution unit */
  (void) WriteBlobMSBShort(image,units); /* width unit */
  (void) WriteBlobMSBLong(image,(unsigned int) (y_resolution+0.5));
  (void) WriteBlobMSBShort(image,units); /* vertical resolution unit */
  (void) WriteBlobMSBShort(image,units); /* height unit */
}

static void RemoveICCProfileFromResourceBlock(StringInfo *bim_profile)
{
  register const unsigned char
    *p;

  size_t
    length;

  unsigned char
    *datum;

  unsigned int
    count,
    long_sans;

  unsigned short
    id,
    short_sans;

  length=GetStringInfoLength(bim_profile);
  if (length < 16)
    return;
  datum=GetStringInfoDatum(bim_profile);
  for (p=datum; (p >= datum) && (p < (datum+length-16)); )
  {
    register unsigned char
      *q;

    q=(unsigned char *) p;
    if (LocaleNCompare((const char *) p,"8BIM",4) != 0)
      break;
    p=PushLongPixel(MSBEndian,p,&long_sans);
    p=PushShortPixel(MSBEndian,p,&id);
    p=PushShortPixel(MSBEndian,p,&short_sans);
    p=PushLongPixel(MSBEndian,p,&count);
    if (id == 0x0000040f)
      {
        (void) CopyMagickMemory(q,q+PSDQuantum(count)+12,length-
          (PSDQuantum(count)+12)-(q-datum));
        SetStringInfoLength(bim_profile,length-(PSDQuantum(count)+12));
        break;
      }
    p+=count;
    if ((count & 0x01) != 0)
      p++;
  }
}

static void RemoveResolutionFromResourceBlock(StringInfo *bim_profile)
{
  register const unsigned char
    *p;

  size_t
    length;

  unsigned char
    *datum;

  unsigned int
    count,
    long_sans;

  unsigned short
    id,
    short_sans;

  length=GetStringInfoLength(bim_profile);
  if (length < 16)
    return;
  datum=GetStringInfoDatum(bim_profile);
  for (p=datum; (p >= datum) && (p < (datum+length-16)); )
  {
    register unsigned char
      *q;

    q=(unsigned char *) p;
    if (LocaleNCompare((const char *) p,"8BIM",4) != 0)
      break;
    p=PushLongPixel(MSBEndian,p,&long_sans);
    p=PushShortPixel(MSBEndian,p,&id);
    p=PushShortPixel(MSBEndian,p,&short_sans);
    p=PushLongPixel(MSBEndian,p,&count);
    if ((id == 0x000003ed) && (PSDQuantum(count) < (ssize_t) (length-12)))
      {
        (void) CopyMagickMemory(q,q+PSDQuantum(count)+12,length-
          (PSDQuantum(count)+12)-(q-datum));
        SetStringInfoLength(bim_profile,length-(PSDQuantum(count)+12));
        break;
      }
    p+=count;
    if ((count & 0x01) != 0)
      p++;
  }
}

static MagickBooleanType WritePSDImage(const ImageInfo *image_info,Image *image)
{
  const char
    *property;

  const StringInfo
    *icc_profile;

  Image
    *base_image,
    *next_image;

  MagickBooleanType
    status;

  PSDInfo
    psd_info;

  register ssize_t
    i;

  size_t
    channel_size,
    channelLength,
    layer_count,
    layer_info_size,
    length,
    num_channels,
    packet_size,
    rounded_layer_info_size;

  StringInfo
    *bim_profile;

  /*
    Open image file.
  */
  assert(image_info != (const ImageInfo *) NULL);
  assert(image_info->signature == MagickSignature);
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  status=OpenBlob(image_info,image,WriteBinaryBlobMode,&image->exception);
  if (status == MagickFalse)
    return(status);
  packet_size=(size_t) (image->depth > 8 ? 6 : 3);
  if (image->matte != MagickFalse)
    packet_size+=image->depth > 8 ? 2 : 1;
  psd_info.version=1;
  if ((LocaleCompare(image_info->magick,"PSB") == 0) ||
      (image->columns > 30000) || (image->rows > 30000))
    psd_info.version=2;
  (void) WriteBlob(image,4,(const unsigned char *) "8BPS");
  (void) WriteBlobMSBShort(image,psd_info.version);  /* version */
  for (i=1; i <= 6; i++)
    (void) WriteBlobByte(image, 0);  /* 6 bytes of reserved */
  if (SetImageGray(image,&image->exception) != MagickFalse)
    num_channels=(image->matte != MagickFalse ? 2UL : 1UL);
  else
    if ((image_info->type != TrueColorType) && (image_info->type !=
         TrueColorMatteType) && (image->storage_class == PseudoClass))
      num_channels=(image->matte != MagickFalse ? 2UL : 1UL);
    else
      {
        if (image->storage_class == PseudoClass)
          (void) SetImageStorageClass(image,DirectClass);
        if (image->colorspace != CMYKColorspace)
          num_channels=(image->matte != MagickFalse ? 4UL : 3UL);
        else
          num_channels=(image->matte != MagickFalse ? 5UL : 4UL);
      }
  (void) WriteBlobMSBShort(image,(unsigned short) num_channels);
  (void) WriteBlobMSBLong(image,(unsigned int) image->rows);
  (void) WriteBlobMSBLong(image,(unsigned int) image->columns);
  if (IsGrayImage(image,&image->exception) != MagickFalse)
    {
      MagickBooleanType
        monochrome;

      /*
        Write depth & mode.
      */
      monochrome=IsMonochromeImage(image,&image->exception) &&
        (image->depth == 1) ? MagickTrue : MagickFalse;
      (void) WriteBlobMSBShort(image,(unsigned short)
        (monochrome != MagickFalse ? 1 : image->depth > 8 ? 16 : 8));
      (void) WriteBlobMSBShort(image,(unsigned short)
        (monochrome != MagickFalse ? BitmapMode : GrayscaleMode));
    }
  else
    {
      (void) WriteBlobMSBShort(image,(unsigned short) (image->storage_class ==
        PseudoClass ? 8 : image->depth > 8 ? 16 : 8));
      if (((image_info->colorspace != UndefinedColorspace) ||
           (image->colorspace != CMYKColorspace)) &&
          (image_info->colorspace != CMYKColorspace))
        {
          (void) TransformImageColorspace(image,sRGBColorspace);
          (void) WriteBlobMSBShort(image,(unsigned short)
            (image->storage_class == PseudoClass ? IndexedMode : RGBMode));
        }
      else
        {
          if (image->colorspace != CMYKColorspace)
            (void) TransformImageColorspace(image,CMYKColorspace);
          (void) WriteBlobMSBShort(image,CMYKMode);
        }
    }
  if ((IsGrayImage(image,&image->exception) != MagickFalse) ||
      (image->storage_class == DirectClass) || (image->colors > 256))
    (void) WriteBlobMSBLong(image,0);
  else
    {
      /*
        Write PSD raster colormap.
      */
      (void) WriteBlobMSBLong(image,768);
      for (i=0; i < (ssize_t) image->colors; i++)
        (void) WriteBlobByte(image,ScaleQuantumToChar(image->colormap[i].red));
      for ( ; i < 256; i++)
        (void) WriteBlobByte(image,0);
      for (i=0; i < (ssize_t) image->colors; i++)
        (void) WriteBlobByte(image,ScaleQuantumToChar(
          image->colormap[i].green));
      for ( ; i < 256; i++)
        (void) WriteBlobByte(image,0);
      for (i=0; i < (ssize_t) image->colors; i++)
        (void) WriteBlobByte(image,ScaleQuantumToChar(image->colormap[i].blue));
      for ( ; i < 256; i++)
        (void) WriteBlobByte(image,0);
    }
  /*
    Image resource block.
  */
  length=28; /* 0x03EB */
  bim_profile=(StringInfo *) GetImageProfile(image,"8bim");
  icc_profile=GetImageProfile(image,"icc");
  if (bim_profile != (StringInfo *) NULL)
    {
      bim_profile=CloneStringInfo(bim_profile);
      if (icc_profile != (StringInfo *) NULL)
        RemoveICCProfileFromResourceBlock(bim_profile);
      RemoveResolutionFromResourceBlock(bim_profile);
      length+=PSDQuantum(GetStringInfoLength(bim_profile));
    }
  if (icc_profile != (const StringInfo *) NULL)
    length+=PSDQuantum(GetStringInfoLength(icc_profile))+12;
  (void) WriteBlobMSBLong(image,(unsigned int) length);
  WriteResolutionResourceBlock(image);
  if (bim_profile != (StringInfo *) NULL)
    {
      (void) WriteBlob(image,GetStringInfoLength(bim_profile),
        GetStringInfoDatum(bim_profile));
      bim_profile=DestroyStringInfo(bim_profile);
    }
  if (icc_profile != (StringInfo *) NULL)
    {
      (void) WriteBlob(image,4,(const unsigned char *) "8BIM");
      (void) WriteBlobMSBShort(image,0x0000040F);
      (void) WriteBlobMSBShort(image,0);
      (void) WriteBlobMSBLong(image,(unsigned int) GetStringInfoLength(
        icc_profile));
      (void) WriteBlob(image,GetStringInfoLength(icc_profile),
        GetStringInfoDatum(icc_profile));
      if ((MagickOffsetType) GetStringInfoLength(icc_profile) !=
          PSDQuantum(GetStringInfoLength(icc_profile)))
        (void) WriteBlobByte(image,0);
    }
  layer_count=0;
  layer_info_size=2;
  base_image=GetNextImageInList(image);
  if ((image->matte != MagickFalse) && (base_image == (Image *) NULL))
    base_image=image;
  next_image=base_image;
  while ( next_image != NULL )
  {
    packet_size=next_image->depth > 8 ? 2UL : 1UL;
    if (IsGrayImage(next_image,&image->exception) != MagickFalse)
      num_channels=next_image->matte != MagickFalse ? 2UL : 1UL;
    else
      if (next_image->storage_class == PseudoClass)
        num_channels=next_image->matte != MagickFalse ? 2UL : 1UL;
      else
        if (next_image->colorspace != CMYKColorspace)
          num_channels=next_image->matte != MagickFalse ? 4UL : 3UL;
        else
          num_channels=next_image->matte != MagickFalse ? 5UL : 4UL;
    channelLength=(size_t) (next_image->columns*next_image->rows*packet_size+2);
    layer_info_size+=(size_t) (4*4+2+num_channels*6+(psd_info.version == 1 ? 8 :
      16)+4*1+4+num_channels*channelLength);
    property=(const char *) GetImageProperty(next_image,"label");
    if (property == (const char *) NULL)
      layer_info_size+=16;
    else
      {
        size_t
          length;

        length=strlen(property);
        layer_info_size+=8+length+(4-(length % 4));
      }
    layer_count++;
    next_image=GetNextImageInList(next_image);
  }
  if (layer_count == 0)
    (void) SetPSDSize(&psd_info,image,0);
  else
    {
      CompressionType
        compression;

      (void) SetPSDSize(&psd_info,image,layer_info_size+
        (psd_info.version == 1 ? 8 : 16));
      if ((layer_info_size/2) != ((layer_info_size+1)/2))
        rounded_layer_info_size=layer_info_size+1;
      else
        rounded_layer_info_size=layer_info_size;
      (void) SetPSDSize(&psd_info,image,rounded_layer_info_size);
      if (image->matte != MagickFalse)
        (void) WriteBlobMSBShort(image,-(unsigned short) layer_count);
      else
        (void) WriteBlobMSBShort(image,(unsigned short) layer_count);
      layer_count=1;
      compression=base_image->compression;
      for (next_image=base_image; next_image != NULL; )
      {
        next_image->compression=NoCompression;
        (void) WriteBlobMSBLong(image,(unsigned int) next_image->page.y);
        (void) WriteBlobMSBLong(image,(unsigned int) next_image->page.x);
        (void) WriteBlobMSBLong(image,(unsigned int) (next_image->page.y+
          next_image->rows));
        (void) WriteBlobMSBLong(image,(unsigned int) (next_image->page.x+
          next_image->columns));
        packet_size=next_image->depth > 8 ? 2UL : 1UL;
        channel_size=(unsigned int) ((packet_size*next_image->rows*
          next_image->columns)+2);
        if ((IsGrayImage(next_image,&image->exception) != MagickFalse) ||
            (next_image->storage_class == PseudoClass))
          {
             (void) WriteBlobMSBShort(image,(unsigned short)
               (next_image->matte != MagickFalse ? 2 : 1));
             (void) WriteBlobMSBShort(image,0);
             (void) SetPSDSize(&psd_info,image,channel_size);
             if (next_image->matte != MagickFalse)
               {
                 (void) WriteBlobMSBShort(image,(unsigned short) -1);
                 (void) SetPSDSize(&psd_info,image,channel_size);
               }
           }
          else
            if (next_image->colorspace != CMYKColorspace)
              {
                (void) WriteBlobMSBShort(image,(unsigned short)
                  (next_image->matte != MagickFalse ? 4 : 3));
               (void) WriteBlobMSBShort(image,0);
               (void) SetPSDSize(&psd_info,image,channel_size);
               (void) WriteBlobMSBShort(image,1);
               (void) SetPSDSize(&psd_info,image,channel_size);
               (void) WriteBlobMSBShort(image,2);
               (void) SetPSDSize(&psd_info,image,channel_size);
               if (next_image->matte!= MagickFalse )
                 {
                   (void) WriteBlobMSBShort(image,(unsigned short) -1);
                   (void) SetPSDSize(&psd_info,image,channel_size);
                 }
             }
           else
             {
               (void) WriteBlobMSBShort(image,(unsigned short)
                 (next_image->matte ? 5 : 4));
               (void) WriteBlobMSBShort(image,0);
               (void) SetPSDSize(&psd_info,image,channel_size);
               (void) WriteBlobMSBShort(image,1);
               (void) SetPSDSize(&psd_info,image,channel_size);
               (void) WriteBlobMSBShort(image,2);
               (void) SetPSDSize(&psd_info,image,channel_size);
               (void) WriteBlobMSBShort(image,3);
               (void) SetPSDSize(&psd_info,image,channel_size);
               if (next_image->matte)
                 {
                   (void) WriteBlobMSBShort(image,(unsigned short) -1);
                   (void) SetPSDSize(&psd_info,image,channel_size);
                 }
             }
        (void) WriteBlob(image,4,(const unsigned char *) "8BIM");
        (void) WriteBlob(image,4,(const unsigned char *)
          CompositeOperatorToPSDBlendMode(next_image->compose));
        (void) WriteBlobByte(image,255); /* layer opacity */
        (void) WriteBlobByte(image,0);
        (void) WriteBlobByte(image,next_image->compose==NoCompositeOp ?
          1 << 0x02 : 1); /* layer properties - visible, etc. */
        (void) WriteBlobByte(image,0);
        property=(const char *) GetImageProperty(next_image,"label");
        if (property == (const char *) NULL)
          {
            char
              layer_name[MaxTextExtent];

            (void) WriteBlobMSBLong(image,16);
            (void) WriteBlobMSBLong(image,0);
            (void) WriteBlobMSBLong(image,0);
            (void) FormatLocaleString(layer_name,MaxTextExtent,"L%04ld",(long)
              layer_count++);
            WritePascalString(image,layer_name,4);
          }
        else
          {
            size_t
              length;

            length=strlen(property);
            (void) WriteBlobMSBLong(image,(unsigned int) (length+(4-
              (length % 4))+8));
            (void) WriteBlobMSBLong(image,0);
            (void) WriteBlobMSBLong(image,0);
            WritePascalString(image,property,4);
          }
        next_image=GetNextImageInList(next_image);
      }
      /*
        Now the image data!
      */
      next_image=base_image;
      while (next_image != NULL)
      {
        status=WriteImageChannels(&psd_info,image_info,image,next_image,
          MagickTrue);
        next_image=GetNextImageInList(next_image);
      }
      (void) WriteBlobMSBLong(image,0);  /* user mask data */
      base_image->compression=compression;
    }
  /*
    Write composite image.
  */
  if (status != MagickFalse)
    status=WriteImageChannels(&psd_info,image_info,image,image,MagickFalse);
  (void) CloseBlob(image);
  return(status);
}