/* [<][>][^][v][top][bottom][index][help] */
DEFINITIONS
This source file includes following definitions.
- DecodeImage
- EncodeImage
- IsDIB
- ReadDIBImage
- RegisterDIBImage
- UnregisterDIBImage
- WriteDIBImage
/*
% Copyright (C) 2003 GraphicsMagick Group
% Copyright (C) 2002 ImageMagick Studio
%
% This program is covered by multiple licenses, which are described in
% Copyright.txt. You should have received a copy of Copyright.txt with this
% package; otherwise see http://www.graphicsmagick.org/www/Copyright.html.
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% DDDD IIIII BBBB %
% D D I B B %
% D D I BBBB %
% D D I B B %
% DDDD IIIII BBBB %
% %
% %
% Read/Write Windows DIB Image Format. %
% %
% %
% Software Design %
% John Cristy %
% July 1992 %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%
*/
/*
Include declarations.
*/
#include "magick/studio.h"
#include "magick/analyze.h"
#include "magick/blob.h"
#include "magick/colormap.h"
#include "magick/magick.h"
#include "magick/monitor.h"
#include "magick/pixel_cache.h"
#include "magick/render.h"
#include "magick/transform.h"
#include "magick/utility.h"
/*
Typedef declarations.
*/
typedef struct _DIBInfo
{
unsigned long
size;
long
width,
height;
unsigned short
planes,
bits_per_pixel;
unsigned long
compression,
image_size,
x_pixels,
y_pixels,
number_colors,
colors_important;
unsigned short
red_mask,
green_mask,
blue_mask,
alpha_mask;
long
colorspace;
PointInfo
red_primary,
green_primary,
blue_primary,
gamma_scale;
} DIBInfo;
/*
Forward declarations.
*/
static unsigned int
WriteDIBImage(const ImageInfo *,Image *);
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% D e c o d e I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Method DecodeImage unpacks the packed image pixels into runlength-encoded
% pixel packets.
%
% The format of the DecodeImage method is:
%
% unsigned int DecodeImage(Image *image,const unsigned long compression,
% unsigned char *pixels)
%
% A description of each parameter follows:
%
% o status: Method DecodeImage returns True if all the pixels are
% uncompressed without error, otherwise False.
%
% o image: The address of a structure of type Image.
%
% o compression: A value of 1 means the compressed pixels are runlength
% encoded for a 256-color bitmap. A value of 2 means a 16-color bitmap.
%
% o pixels: The address of a byte (8 bits) array of pixel data created by
% the decoding process.
%
%
*/
static unsigned int DecodeImage(Image *image,const unsigned long compression,
unsigned char *pixels)
{
long
byte,
count,
y;
register long
i,
x;
register unsigned char
*q;
unsigned char
*end;
assert(image != (Image *) NULL);
assert(pixels != (unsigned char *) NULL);
(void) memset(pixels,0,image->columns*image->rows);
byte=0;
x=0;
q=pixels;
end=pixels + (size_t) image->columns*image->rows;
for (y=0; y < (long) image->rows; )
{
if (q < pixels || q >= end)
break;
count=ReadBlobByte(image);
if (count == EOF)
break;
if (count != 0)
{
count=Min(count, end - q);
/*
Encoded mode.
*/
byte=ReadBlobByte(image);
for (i=0; i < count; i++)
{
if (compression == 1)
*q++=(unsigned char) byte;
else
*q++=(unsigned char)
((i & 0x01) ? (byte & 0x0f) : ((byte >> 4) & 0x0f));
x++;
}
}
else
{
/*
Escape mode.
*/
count=ReadBlobByte(image);
if (count == 0x01)
return(True);
switch ((int) count)
{
case 0x00:
{
/*
End of line.
*/
x=0;
y++;
q=pixels+y*image->columns;
break;
}
case 0x02:
{
/*
Delta mode.
*/
x+=ReadBlobByte(image);
y+=ReadBlobByte(image);
q=pixels+y*image->columns+x;
break;
}
default:
{
/*
Absolute mode.
*/
count=Min(count, end - q);
for (i=0; i < count; i++)
{
if (compression == 1)
*q++=ReadBlobByte(image);
else
{
if ((i & 0x01) == 0)
byte=ReadBlobByte(image);
*q++=(unsigned char)
((i & 0x01) ? (byte & 0x0f) : ((byte >> 4) & 0x0f));
}
x++;
}
/*
Read pad byte.
*/
if (compression == 1)
{
if (count & 0x01)
(void) ReadBlobByte(image);
}
else
if (((count & 0x03) == 1) || ((count & 0x03) == 2))
(void) ReadBlobByte(image);
break;
}
}
}
if (QuantumTick(y,image->rows))
if (!MagickMonitorFormatted(y,image->rows,&image->exception,
LoadImageText,image->filename,
image->columns,image->rows))
break;
}
(void) ReadBlobByte(image); /* end of line */
(void) ReadBlobByte(image);
return(True);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% E n c o d e I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Method EncodeImage compresses pixels using a runlength encoded format.
%
% The format of the EncodeImage method is:
%
% static unsigned int EncodeImage(Image *image,
% const unsigned long bytes_per_line,const unsigned char *pixels,
% unsigned char *compressed_pixels)
%
% A description of each parameter follows:
%
% o status: Method EncodeImage returns the number of bytes in the
% runlength encoded compress_pixels array.
%
% o image: A pointer to an Image structure.
%
% o bytes_per_line: The number of bytes in a scanline of compressed pixels
%
% o pixels: The address of a byte (8 bits) array of pixel data created by
% the compression process.
%
% o compressed_pixels: The address of a byte (8 bits) array of compressed
% pixel data.
%
%
*/
static size_t EncodeImage(Image *image,const unsigned long bytes_per_line,
const unsigned char *pixels,unsigned char *compressed_pixels)
{
long
y;
register const unsigned char
*p;
register long
i,
x;
register unsigned char
*q;
/*
Runlength encode pixels.
*/
assert(image != (Image *) NULL);
assert(pixels != (const unsigned char *) NULL);
assert(compressed_pixels != (unsigned char *) NULL);
p=pixels;
q=compressed_pixels;
i=0;
for (y=0; y < (long) image->rows; y++)
{
for (x=0; x < (long) bytes_per_line; x+=i)
{
/*
Determine runlength.
*/
for (i=1; ((x+i) < (long) bytes_per_line); i++)
if ((*(p+i) != *p) || (i == 255U))
break;
*q++=(unsigned char) i;
*q++=(*p);
p+=i;
}
/*
End of line.
*/
*q++=0x00;
*q++=0x00;
if (QuantumTick(y,image->rows))
if (!MagickMonitorFormatted(y,image->rows,&image->exception,
SaveImageText,image->filename,
image->columns,image->rows))
break;
}
/*
End of bitmap.
*/
*q++=0;
*q++=0x01;
return(q-compressed_pixels);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% I s D I B %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Method IsDIB returns True if the image format type, identified by the
% magick string, is DIB.
%
% The format of the IsDIB method is:
%
% unsigned int IsDIB(const unsigned char *magick,const size_t length)
%
% A description of each parameter follows:
%
% o status: Method IsDIB returns True if the image format type is DIB.
%
% o magick: This string is generally the first few bytes of an image file
% or blob.
%
% o length: Specifies the length of the magick string.
%
%
*/
static unsigned int IsDIB(const unsigned char *magick,const size_t length)
{
if (length < 2)
return(False);
if( (*magick == 40) && (*(magick+1)==0))
return(True);
return(False);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R e a d D I B I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Method ReadDIBImage reads a Microsoft Windows bitmap 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 ReadDIBImage method is:
%
% image=ReadDIBImage(image_info)
%
% A description of each parameter follows:
%
% o image: Method ReadDIBImage returns a pointer to the image after
% reading. A null image is returned if there is a memory shortage or
% if the image cannot be read.
%
% o image_info: Specifies a pointer to a ImageInfo structure.
%
% o exception: return any errors or warnings in this structure.
%
%
*/
static Image *ReadDIBImage(const ImageInfo *image_info,ExceptionInfo *exception)
{
DIBInfo
dib_info;
Image
*image;
IndexPacket
index;
long
bit,
y;
register IndexPacket
*indexes;
register long
x;
register PixelPacket
*q;
register long
i;
register unsigned char
*p;
size_t
length;
unsigned char
*pixels;
unsigned int
status;
unsigned long
bytes_per_line;
/*
Open image file.
*/
assert(image_info != (const ImageInfo *) NULL);
assert(image_info->signature == MagickSignature);
assert(exception != (ExceptionInfo *) NULL);
assert(exception->signature == MagickSignature);
image=AllocateImage(image_info);
status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
if (status == False)
ThrowReaderException(FileOpenError,UnableToOpenFile,image);
/*
Determine if this is a DIB file.
*/
(void) memset(&dib_info,0,sizeof(DIBInfo));
dib_info.size=ReadBlobLSBLong(image);
if (dib_info.size!=40)
ThrowReaderException(CorruptImageError,ImproperImageHeader,image);
/*
Microsoft Windows 3.X DIB image file.
*/
/*
BMP v3 defines width and hight as signed LONG (32 bit) values. If
height is a positive number, then the image is a "bottom-up"
bitmap with origin in the lower-left corner. If height is a
negative number, then the image is a "top-down" bitmap with the
origin in the upper-left corner. The meaning of negative values
is not defined for width.
*/
dib_info.width=(magick_int32_t) ReadBlobLSBLong(image);
dib_info.height=(magick_int32_t) ReadBlobLSBLong(image);
dib_info.planes=ReadBlobLSBShort(image);
dib_info.bits_per_pixel=ReadBlobLSBShort(image);
dib_info.compression=ReadBlobLSBLong(image);
dib_info.image_size=ReadBlobLSBLong(image);
dib_info.x_pixels=ReadBlobLSBLong(image);
dib_info.y_pixels=ReadBlobLSBLong(image);
dib_info.number_colors=ReadBlobLSBLong(image);
dib_info.colors_important=ReadBlobLSBLong(image);
if ((dib_info.compression == 3) && ((dib_info.bits_per_pixel == 16) ||
(dib_info.bits_per_pixel == 32)))
{
dib_info.red_mask=ReadBlobLSBShort(image);
dib_info.green_mask=ReadBlobLSBShort(image);
dib_info.blue_mask=ReadBlobLSBShort(image);
}
if (dib_info.width <= 0)
ThrowReaderException(CorruptImageWarning,NegativeOrZeroImageSize,image);
if (dib_info.height == 0)
ThrowReaderException(CorruptImageWarning,NegativeOrZeroImageSize,image);
image->matte=dib_info.bits_per_pixel == 32;
image->columns=AbsoluteValue(dib_info.width);
image->rows=AbsoluteValue(dib_info.height);
image->depth=8;
if ((dib_info.number_colors != 0) || (dib_info.bits_per_pixel < 16))
{
image->storage_class=PseudoClass;
image->colors=dib_info.number_colors;
if (image->colors == 0)
image->colors=1L << dib_info.bits_per_pixel;
}
if(image_info->size)
{
int
flags;
RectangleInfo
geometry;
flags=GetGeometry(image_info->size,&geometry.x,&geometry.y,
&geometry.width,&geometry.height);
if ((flags & WidthValue) && (geometry.width != 0)
&& (geometry.width < image->columns))
image->columns=geometry.width;
if ((flags & HeightValue) && (geometry.height != 0)
&& (geometry.height < image->rows))
image->rows=geometry.height;
}
if (image->storage_class == PseudoClass)
{
unsigned char
*dib_colormap;
unsigned int
packet_size;
/*
Read DIB raster colormap.
*/
if (!AllocateImageColormap(image,image->colors))
ThrowReaderException(ResourceLimitError,MemoryAllocationFailed,image);
dib_colormap=MagickAllocateArray(unsigned char *,image->colors,4);
if (dib_colormap == (unsigned char *) NULL)
ThrowReaderException(ResourceLimitError,MemoryAllocationFailed,image);
packet_size=4;
(void) ReadBlob(image,packet_size*image->colors,(char *) dib_colormap);
p=dib_colormap;
for (i=0; i < (long) image->colors; i++)
{
image->colormap[i].blue=ScaleCharToQuantum(*p++);
image->colormap[i].green=ScaleCharToQuantum(*p++);
image->colormap[i].red=ScaleCharToQuantum(*p++);
if (packet_size == 4)
p++;
}
MagickFreeMemory(dib_colormap);
}
/*
Read image data.
*/
if (dib_info.compression == 2)
dib_info.bits_per_pixel<<=1;
bytes_per_line=4*((image->columns*dib_info.bits_per_pixel+31)/32);
length=bytes_per_line*image->rows;
pixels=MagickAllocateArray(unsigned char *,
image->rows,
Max(bytes_per_line,image->columns+1));
if (pixels == (unsigned char *) NULL)
ThrowReaderException(ResourceLimitError,MemoryAllocationFailed,image);
if ((dib_info.compression == 0) || (dib_info.compression == 3))
(void) ReadBlob(image,length,(char *) pixels);
else
{
/*
Convert run-length encoded raster pixels.
DecodeImage expects that pixels array is rows*columns bytes.
*/
status=DecodeImage(image,dib_info.compression,pixels);
if (status == False)
ThrowReaderException(CorruptImageError,UnableToRunlengthDecodeImage,
image);
}
/*
Initialize image structure.
*/
image->units=PixelsPerCentimeterResolution;
image->x_resolution=dib_info.x_pixels/100.0;
image->y_resolution=dib_info.y_pixels/100.0;
/*
Convert DIB raster image to pixel packets.
*/
switch (dib_info.bits_per_pixel)
{
case 1:
{
/*
Convert bitmap scanline.
*/
for (y=(long) image->rows-1; y >= 0; y--)
{
p=pixels+(image->rows-y-1)*bytes_per_line;
q=SetImagePixels(image,0,y,image->columns,1);
if (q == (PixelPacket *) NULL)
break;
indexes=AccessMutableIndexes(image);
for (x=0; x < ((long) image->columns-7); x+=8)
{
for (bit=0; bit < 8; bit++)
{
index=((*p) & (0x80 >> bit) ? 0x01 : 0x00);
indexes[x+bit]=index;
*q++=image->colormap[index];
}
p++;
}
if ((image->columns % 8) != 0)
{
for (bit=0; bit < (long) (image->columns % 8); bit++)
{
index=((*p) & (0x80 >> bit) ? 0x01 : 0x00);
indexes[x+bit]=index;
*q++=image->colormap[index];
}
p++;
}
if (!SyncImagePixels(image))
break;
if (image->previous == (Image *) NULL)
if (QuantumTick(y,image->rows))
{
status=MagickMonitorFormatted(image->rows-y-1,image->rows,
exception,LoadImageText,
image->filename,
image->columns,image->rows);
if (status == False)
break;
}
}
break;
}
case 4:
{
/*
Convert PseudoColor scanline.
*/
for (y=(long) image->rows-1; y >= 0; y--)
{
p=pixels+(image->rows-y-1)*bytes_per_line;
q=SetImagePixels(image,0,y,image->columns,1);
if (q == (PixelPacket *) NULL)
break;
indexes=AccessMutableIndexes(image);
for (x=0; x < ((long) image->columns-1); x+=2)
{
index=(IndexPacket) ((*p >> 4) & 0xf);
VerifyColormapIndex(image,index);
indexes[x]=index;
*q++=image->colormap[index];
index=(IndexPacket) (*p & 0xf);
VerifyColormapIndex(image,index);
indexes[x+1]=index;
*q++=image->colormap[index];
p++;
}
if ((image->columns % 2) != 0)
{
index=(IndexPacket) ((*p >> 4) & 0xf);
VerifyColormapIndex(image,index);
indexes[x]=index;
*q++=image->colormap[index];
p++;
}
if (!SyncImagePixels(image))
break;
if (image->previous == (Image *) NULL)
if (QuantumTick(y,image->rows))
{
status=MagickMonitorFormatted(image->rows-y-1,image->rows,
exception,LoadImageText,
image->filename,
image->columns,image->rows);
if (status == False)
break;
}
}
break;
}
case 8:
{
/*
Convert PseudoColor scanline.
*/
if ((dib_info.compression == 1) || (dib_info.compression == 2))
bytes_per_line=image->columns;
for (y=(long) image->rows-1; y >= 0; y--)
{
p=pixels+(image->rows-y-1)*bytes_per_line;
q=SetImagePixels(image,0,y,image->columns,1);
if (q == (PixelPacket *) NULL)
break;
indexes=AccessMutableIndexes(image);
for (x=0; x < (long) image->columns; x++)
{
index=(IndexPacket) (*p);
VerifyColormapIndex(image,index);
indexes[x]=index;
*q=image->colormap[index];
p++;
q++;
}
if (!SyncImagePixels(image))
break;
if (image->previous == (Image *) NULL)
if (QuantumTick(y,image->rows))
{
status=MagickMonitorFormatted(image->rows-y-1,image->rows,
exception,LoadImageText,
image->filename,
image->columns,image->rows);
if (status == False)
break;
}
}
break;
}
case 16:
{
unsigned short
word;
/*
Convert PseudoColor scanline.
*/
image->storage_class=DirectClass;
if (dib_info.compression == 1)
bytes_per_line=2*image->columns;
for (y=(long) image->rows-1; y >= 0; y--)
{
p=pixels+(image->rows-y-1)*bytes_per_line;
q=SetImagePixels(image,0,y,image->columns,1);
if (q == (PixelPacket *) NULL)
break;
for (x=0; x < (long) image->columns; x++)
{
word=(*p++);
word|=(*p++ << 8);
if (dib_info.red_mask == 0)
{
q->red=ScaleCharToQuantum(ScaleColor5to8((word >> 10) & 0x1f));
q->green=ScaleCharToQuantum(ScaleColor5to8((word >> 5) & 0x1f));
q->blue=ScaleCharToQuantum(ScaleColor5to8(word & 0x1f));
}
else
{
q->red=ScaleCharToQuantum(ScaleColor5to8((word >> 11) & 0x1f));
q->green=ScaleCharToQuantum(ScaleColor6to8((word >> 5) & 0x3f));
q->blue=ScaleCharToQuantum(ScaleColor5to8(word & 0x1f));
}
q++;
}
if (!SyncImagePixels(image))
break;
if (image->previous == (Image *) NULL)
if (QuantumTick(y,image->rows))
{
status=MagickMonitorFormatted(image->rows-y-1,image->rows,
exception,LoadImageText,
image->filename,
image->columns,image->rows);
if (status == False)
break;
}
}
break;
}
case 24:
case 32:
{
/*
Convert DirectColor scanline.
*/
for (y=(long) image->rows-1; y >= 0; y--)
{
p=pixels+(image->rows-y-1)*bytes_per_line;
q=SetImagePixels(image,0,y,image->columns,1);
if (q == (PixelPacket *) NULL)
break;
for (x=0; x < (long) image->columns; x++)
{
q->blue=ScaleCharToQuantum(*p++);
q->green=ScaleCharToQuantum(*p++);
q->red=ScaleCharToQuantum(*p++);
if (image->matte)
q->opacity=ScaleCharToQuantum(*p++);
q++;
}
if (!SyncImagePixels(image))
break;
if (image->previous == (Image *) NULL)
if (QuantumTick(y,image->rows))
{
status=MagickMonitorFormatted(image->rows-y-1,image->rows,
exception,LoadImageText,
image->filename,
image->columns,image->rows);
if (status == False)
break;
}
}
break;
}
default:
ThrowReaderException(CorruptImageError,ImproperImageHeader,image)
}
MagickFreeMemory(pixels);
if (EOFBlob(image))
ThrowException(exception,CorruptImageError,UnexpectedEndOfFile,
image->filename);
if (dib_info.height < 0)
{
Image
*flipped_image;
/*
Correct image orientation.
*/
flipped_image=FlipImage(image,exception);
if (flipped_image == (Image *) NULL)
{
DestroyImageList(image);
return((Image *) NULL);
}
DestroyBlobInfo(flipped_image->blob);
flipped_image->blob=ReferenceBlob(image->blob);
DestroyImage(image);
image=flipped_image;
}
CloseBlob(image);
return(image);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R e g i s t e r D I B I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Method RegisterDIBImage adds attributes for the DIB image format to
% the list of supported formats. The attributes 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 RegisterDIBImage method is:
%
% RegisterDIBImage(void)
%
*/
ModuleExport void RegisterDIBImage(void)
{
MagickInfo
*entry;
entry=SetMagickInfo("DIB");
entry->decoder=(DecoderHandler) ReadDIBImage;
entry->encoder=(EncoderHandler) WriteDIBImage;
entry->magick=(MagickHandler) IsDIB;
entry->adjoin=False;
entry->stealth=True;
entry->description="Microsoft Windows 3.X Packed Device-Independent Bitmap";
entry->module="DIB";
(void) RegisterMagickInfo(entry);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% U n r e g i s t e r D I B I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Method UnregisterDIBImage removes format registrations made by the
% DIB module from the list of supported formats.
%
% The format of the UnregisterDIBImage method is:
%
% UnregisterDIBImage(void)
%
*/
ModuleExport void UnregisterDIBImage(void)
{
(void) UnregisterMagickInfo("DIB");
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% W r i t e D I B I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Method WriteDIBImage writes an image in Microsoft Windows bitmap encoded
% image format.
%
% The format of the WriteDIBImage method is:
%
% unsigned int WriteDIBImage(const ImageInfo *image_info,Image *image)
%
% A description of each parameter follows.
%
% o status: Method WriteDIBImage return True if the image is written.
% False is returned is there is a memory shortage or if the image file
% fails to write.
%
% o image_info: Specifies a pointer to a ImageInfo structure.
%
% o image: A pointer to an Image structure.
%
%
*/
static unsigned int WriteDIBImage(const ImageInfo *image_info,Image *image)
{
DIBInfo
dib_info;
long
y;
register const PixelPacket
*p;
register const IndexPacket
*indexes;
register long
i,
x;
register unsigned char
*q;
unsigned char
*dib_data,
*pixels;
unsigned int
status;
unsigned long
bytes_per_line;
ImageCharacteristics
characteristics;
/*
Open output image file.
*/
assert(image_info != (const ImageInfo *) NULL);
assert(image_info->signature == MagickSignature);
assert(image != (Image *) NULL);
assert(image->signature == MagickSignature);
status=OpenBlob(image_info,image,WriteBinaryBlobMode,&image->exception);
if (status == False)
ThrowWriterException(FileOpenError,UnableToOpenFile,image);
/*
Ensure that image is in an RGB space.
*/
(void) TransformColorspace(image,RGBColorspace);
/*
Analyze image to be written.
*/
if (!GetImageCharacteristics(image,&characteristics,
(OptimizeType == image_info->type),
&image->exception))
{
CloseBlob(image);
return MagickFail;
}
/*
Initialize DIB raster file header.
*/
if (image->storage_class == DirectClass)
{
/*
Full color DIB raster.
*/
dib_info.number_colors=0;
dib_info.bits_per_pixel=image->matte ? 32 : 24;
}
else
{
/*
Colormapped DIB raster.
*/
dib_info.bits_per_pixel=8;
if (characteristics.monochrome)
dib_info.bits_per_pixel=1;
dib_info.number_colors=1 << dib_info.bits_per_pixel;
}
bytes_per_line=4*((image->columns*dib_info.bits_per_pixel+31)/32);
dib_info.size=40;
dib_info.width=(long) image->columns;
dib_info.height=(long) image->rows;
dib_info.planes=1;
dib_info.compression=0;
dib_info.image_size=bytes_per_line*image->rows;
dib_info.x_pixels=75*39;
dib_info.y_pixels=75*39;
if (image->units == PixelsPerInchResolution)
{
dib_info.x_pixels=(unsigned long) (100.0*image->x_resolution/2.54);
dib_info.y_pixels=(unsigned long) (100.0*image->y_resolution/2.54);
}
if (image->units == PixelsPerCentimeterResolution)
{
dib_info.x_pixels=(unsigned long) (100.0*image->x_resolution);
dib_info.y_pixels=(unsigned long) (100.0*image->y_resolution);
}
dib_info.colors_important=dib_info.number_colors;
/*
Convert MIFF to DIB raster pixels.
*/
pixels=MagickAllocateMemory(unsigned char *,dib_info.image_size);
if (pixels == (unsigned char *) NULL)
ThrowWriterException(ResourceLimitError,MemoryAllocationFailed,image);
switch (dib_info.bits_per_pixel)
{
case 1:
{
register unsigned char
bit,
byte;
/*
Convert PseudoClass image to a DIB monochrome image.
*/
for (y=0; y < (long) image->rows; y++)
{
p=AcquireImagePixels(image,0,y,image->columns,1,&image->exception);
if (p == (const PixelPacket *) NULL)
break;
indexes=AccessImmutableIndexes(image);
q=pixels+(image->rows-y-1)*bytes_per_line;
bit=0;
byte=0;
for (x=0; x < (long) image->columns; x++)
{
byte<<=1;
byte|=indexes[x] ? 0x01 : 0x00;
bit++;
if (bit == 8)
{
*q++=byte;
bit=0;
byte=0;
}
p++;
}
if (bit != 0)
*q++=byte << (8-bit);
/* initialize padding bytes */
for (x=(long) (image->columns+7)/8; x < (long) bytes_per_line; x++)
*q++=0x00;
if (image->previous == (Image *) NULL)
if (QuantumTick(y,image->rows))
if (!MagickMonitorFormatted(y,image->rows,&image->exception,
SaveImageText,image->filename,
image->columns,image->rows))
break;
}
break;
}
case 8:
{
/*
Convert PseudoClass packet to DIB pixel.
*/
for (y=0; y < (long) image->rows; y++)
{
p=AcquireImagePixels(image,0,y,image->columns,1,&image->exception);
if (p == (const PixelPacket *) NULL)
break;
indexes=AccessImmutableIndexes(image);
q=pixels+(image->rows-y-1)*bytes_per_line;
for (x=0; x < (long) image->columns; x++)
{
*q++=indexes[x];
p++;
}
/* initialize padding bytes */
for (; x < (long) bytes_per_line; x++)
*q++=0x00;
if (image->previous == (Image *) NULL)
if (QuantumTick(y,image->rows))
if (!MagickMonitorFormatted(y,image->rows,&image->exception,
SaveImageText,image->filename,
image->columns,image->rows))
break;
}
break;
}
case 24:
case 32:
{
/*
Convert DirectClass packet to DIB RGB pixel.
*/
for (y=0; y < (long) image->rows; y++)
{
p=AcquireImagePixels(image,0,y,image->columns,1,&image->exception);
if (p == (const PixelPacket *) NULL)
break;
q=pixels+(image->rows-y-1)*bytes_per_line;
for (x=0; x < (long) image->columns; x++)
{
*q++=ScaleQuantumToChar(p->blue);
*q++=ScaleQuantumToChar(p->green);
*q++=ScaleQuantumToChar(p->red);
if (image->matte)
*q++=ScaleQuantumToChar(p->opacity);
p++;
}
/* initialize padding bytes */
if (dib_info.bits_per_pixel == 24)
{
/* initialize padding bytes */
for (x=3*image->columns; x < (long) bytes_per_line; x++)
*q++=0x00;
}
if (image->previous == (Image *) NULL)
if (QuantumTick(y,image->rows))
if (!MagickMonitorFormatted(y,image->rows,&image->exception,
SaveImageText,image->filename,
image->columns,image->rows))
break;
}
break;
}
}
if (dib_info.bits_per_pixel == 8)
if (image_info->compression != NoCompression)
{
size_t
length;
/*
Convert run-length encoded raster pixels.
*/
length=2*(bytes_per_line+2)*(image->rows+2)+2;
dib_data=MagickAllocateMemory(unsigned char *,length);
if (pixels == (unsigned char *) NULL)
{
MagickFreeMemory(pixels);
ThrowWriterException(ResourceLimitError,MemoryAllocationFailed,
image)
}
dib_info.image_size=EncodeImage(image,bytes_per_line,pixels,dib_data);
MagickFreeMemory(pixels);
pixels=dib_data;
dib_info.compression=1;
}
/*
Write DIB header.
*/
(void) WriteBlobLSBLong(image,dib_info.size);
(void) WriteBlobLSBLong(image,dib_info.width);
(void) WriteBlobLSBLong(image,dib_info.height);
(void) WriteBlobLSBShort(image,dib_info.planes);
(void) WriteBlobLSBShort(image,dib_info.bits_per_pixel);
(void) WriteBlobLSBLong(image,dib_info.compression);
(void) WriteBlobLSBLong(image,dib_info.image_size);
(void) WriteBlobLSBLong(image,dib_info.x_pixels);
(void) WriteBlobLSBLong(image,dib_info.y_pixels);
(void) WriteBlobLSBLong(image,dib_info.number_colors);
(void) WriteBlobLSBLong(image,dib_info.colors_important);
if (image->storage_class == PseudoClass)
{
unsigned char
*dib_colormap;
/*
Dump colormap to file.
*/
dib_colormap=MagickAllocateArray(unsigned char *,
(1 << dib_info.bits_per_pixel),4);
if (dib_colormap == (unsigned char *) NULL)
ThrowWriterException(ResourceLimitError,MemoryAllocationFailed,image);
q=dib_colormap;
for (i=0; i < (long) Min(image->colors,dib_info.number_colors); i++)
{
*q++=ScaleQuantumToChar(image->colormap[i].blue);
*q++=ScaleQuantumToChar(image->colormap[i].green);
*q++=ScaleQuantumToChar(image->colormap[i].red);
*q++=(Quantum) 0x0;
}
for ( ; i < (1L << dib_info.bits_per_pixel); i++)
{
*q++=(Quantum) 0x0;
*q++=(Quantum) 0x0;
*q++=(Quantum) 0x0;
*q++=(Quantum) 0x0;
}
(void) WriteBlob(image,4*(1 << dib_info.bits_per_pixel),
(char *) dib_colormap);
MagickFreeMemory(dib_colormap);
}
(void) WriteBlob(image,dib_info.image_size,(char *) pixels);
MagickFreeMemory(pixels);
CloseBlob(image);
return(True);
}