forked from openkylin/imagemagick
290 lines
10 KiB
C
290 lines
10 KiB
C
/*
|
||
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
||
% %
|
||
% %
|
||
% %
|
||
% SSSSS TTTTT EEEEE GGGG AAA N N OOO %
|
||
% SS T E G A A NN N O O %
|
||
% SSS T EEE G GG AAAAA N N N O O %
|
||
% SS T E G G A A N NN O O %
|
||
% SSSSS T EEEEE GGG A A N N OOO %
|
||
% %
|
||
% %
|
||
% Write A Steganographic Image. %
|
||
% %
|
||
% Software Design %
|
||
% Cristy %
|
||
% July 1992 %
|
||
% %
|
||
% %
|
||
% Copyright 1999-2021 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 %
|
||
% %
|
||
% https://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/blob.h"
|
||
#include "magick/blob-private.h"
|
||
#include "magick/cache.h"
|
||
#include "magick/colormap.h"
|
||
#include "magick/constitute.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/magick.h"
|
||
#include "magick/memory_.h"
|
||
#include "magick/monitor.h"
|
||
#include "magick/monitor-private.h"
|
||
#include "magick/pixel-accessor.h"
|
||
#include "magick/quantum-private.h"
|
||
#include "magick/static.h"
|
||
#include "magick/string_.h"
|
||
#include "magick/module.h"
|
||
|
||
/*
|
||
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
||
% %
|
||
% %
|
||
% %
|
||
% R e a d S T E G A N O I m a g e %
|
||
% %
|
||
% %
|
||
% %
|
||
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
||
%
|
||
% ReadSTEGANOImage() reads a steganographic image hidden within another
|
||
% image type. It allocates the memory necessary for the new Image structure
|
||
% and returns a pointer to the new image.
|
||
%
|
||
% The format of the ReadSTEGANOImage method is:
|
||
%
|
||
% Image *ReadSTEGANOImage(const ImageInfo *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 Image *ReadSTEGANOImage(const ImageInfo *image_info,
|
||
ExceptionInfo *exception)
|
||
{
|
||
#define GetBit(alpha,i) (((size_t) (alpha) >> (size_t) (i)) & 0x01)
|
||
#define SetBit(indexes,i,set) SetPixelIndex(indexes,((set) != 0 ? \
|
||
(size_t) GetPixelIndex(indexes) | (one << (size_t) (i)) : (size_t) \
|
||
GetPixelIndex(indexes) & ~(one << (size_t) (i))))
|
||
|
||
Image
|
||
*image,
|
||
*watermark;
|
||
|
||
ImageInfo
|
||
*read_info;
|
||
|
||
int
|
||
c;
|
||
|
||
MagickBooleanType
|
||
status;
|
||
|
||
PixelPacket
|
||
pixel;
|
||
|
||
IndexPacket
|
||
*indexes;
|
||
|
||
PixelPacket
|
||
*q;
|
||
|
||
ssize_t
|
||
x;
|
||
|
||
size_t
|
||
depth,
|
||
one;
|
||
|
||
ssize_t
|
||
i,
|
||
j,
|
||
k,
|
||
y;
|
||
|
||
/*
|
||
Initialize Image structure.
|
||
*/
|
||
assert(image_info != (const ImageInfo *) NULL);
|
||
assert(image_info->signature == MagickCoreSignature);
|
||
if (image_info->debug != MagickFalse)
|
||
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
|
||
image_info->filename);
|
||
assert(exception != (ExceptionInfo *) NULL);
|
||
assert(exception->signature == MagickCoreSignature);
|
||
one=1;
|
||
image=AcquireImage(image_info);
|
||
if ((image->columns == 0) || (image->rows == 0))
|
||
ThrowReaderException(OptionError,"MustSpecifyImageSize");
|
||
read_info=CloneImageInfo(image_info);
|
||
SetImageInfoBlob(read_info,(void *) NULL,0);
|
||
*read_info->magick='\0';
|
||
watermark=ReadImage(read_info,exception);
|
||
read_info=DestroyImageInfo(read_info);
|
||
if (watermark == (Image *) NULL)
|
||
return(DestroyImageList(image));
|
||
watermark->depth=MAGICKCORE_QUANTUM_DEPTH;
|
||
if (AcquireImageColormap(image,MaxColormapSize) == MagickFalse)
|
||
ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
|
||
if (image_info->ping != MagickFalse)
|
||
{
|
||
(void) CloseBlob(image);
|
||
return(GetFirstImageInList(image));
|
||
}
|
||
status=SetImageExtent(image,image->columns,image->rows);
|
||
if (status == MagickFalse)
|
||
{
|
||
InheritException(exception,&image->exception);
|
||
return(DestroyImageList(image));
|
||
}
|
||
/*
|
||
Get hidden watermark from low-order bits of image.
|
||
*/
|
||
c=0;
|
||
i=0;
|
||
j=0;
|
||
i=(ssize_t) (watermark->depth-1);
|
||
depth=watermark->depth;
|
||
for (k=image->offset; (i >= 0) && (j < (ssize_t) depth); i--)
|
||
{
|
||
for (y=0; (y < (ssize_t) image->rows) && (j < (ssize_t) depth); y++)
|
||
{
|
||
x=0;
|
||
for ( ; (x < (ssize_t) image->columns) && (j < (ssize_t) depth); x++)
|
||
{
|
||
if ((k/(ssize_t) watermark->columns) >= (ssize_t) watermark->rows)
|
||
break;
|
||
(void) GetOneVirtualPixel(watermark,k % (ssize_t) watermark->columns,
|
||
k/(ssize_t) watermark->columns,&pixel,exception);
|
||
q=GetAuthenticPixels(image,x,y,1,1,exception);
|
||
if (q == (PixelPacket *) NULL)
|
||
break;
|
||
indexes=GetAuthenticIndexQueue(image);
|
||
switch (c)
|
||
{
|
||
case 0:
|
||
{
|
||
SetBit(indexes,i,GetBit(pixel.red,j));
|
||
break;
|
||
}
|
||
case 1:
|
||
{
|
||
SetBit(indexes,i,GetBit(pixel.green,j));
|
||
break;
|
||
}
|
||
case 2:
|
||
{
|
||
SetBit(indexes,i,GetBit(pixel.blue,j));
|
||
break;
|
||
}
|
||
}
|
||
if (SyncAuthenticPixels(image,exception) == MagickFalse)
|
||
break;
|
||
c++;
|
||
if (c == 3)
|
||
c=0;
|
||
k++;
|
||
if (k == (ssize_t) (watermark->columns*watermark->columns))
|
||
k=0;
|
||
if (k == image->offset)
|
||
j++;
|
||
}
|
||
}
|
||
status=SetImageProgress(image,LoadImagesTag,(MagickOffsetType) i,depth);
|
||
if (status == MagickFalse)
|
||
break;
|
||
}
|
||
watermark=DestroyImage(watermark);
|
||
(void) SyncImage(image);
|
||
return(GetFirstImageInList(image));
|
||
}
|
||
|
||
/*
|
||
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
||
% %
|
||
% %
|
||
% %
|
||
% R e g i s t e r S T E G A N O I m a g e %
|
||
% %
|
||
% %
|
||
% %
|
||
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
||
%
|
||
% RegisterSTEGANOImage() adds attributes for the STEGANO 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 RegisterSTEGANOImage method is:
|
||
%
|
||
% size_t RegisterSTEGANOImage(void)
|
||
%
|
||
*/
|
||
ModuleExport size_t RegisterSTEGANOImage(void)
|
||
{
|
||
MagickInfo
|
||
*entry;
|
||
|
||
entry=SetMagickInfo("STEGANO");
|
||
entry->decoder=(DecodeImageHandler *) ReadSTEGANOImage;
|
||
entry->format_type=ImplicitFormatType;
|
||
entry->description=ConstantString("Steganographic image");
|
||
entry->magick_module=ConstantString("STEGANO");
|
||
(void) RegisterMagickInfo(entry);
|
||
return(MagickImageCoderSignature);
|
||
}
|
||
|
||
/*
|
||
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
||
% %
|
||
% %
|
||
% %
|
||
% U n r e g i s t e r S T E G A N O I m a g e %
|
||
% %
|
||
% %
|
||
% %
|
||
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
||
%
|
||
% UnregisterSTEGANOImage() removes format registrations made by the
|
||
% STEGANO module from the list of supported formats.
|
||
%
|
||
% The format of the UnregisterSTEGANOImage method is:
|
||
%
|
||
% UnregisterSTEGANOImage(void)
|
||
%
|
||
*/
|
||
ModuleExport void UnregisterSTEGANOImage(void)
|
||
{
|
||
(void) UnregisterMagickInfo("STEGANO");
|
||
}
|