| /* |
| %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
| % % |
| % % |
| % % |
| % 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 1999-2016 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 "MagickCore/studio.h" |
| #include "MagickCore/blob.h" |
| #include "MagickCore/blob-private.h" |
| #include "MagickCore/cache.h" |
| #include "MagickCore/colormap.h" |
| #include "MagickCore/constitute.h" |
| #include "MagickCore/exception.h" |
| #include "MagickCore/exception-private.h" |
| #include "MagickCore/image.h" |
| #include "MagickCore/image-private.h" |
| #include "MagickCore/list.h" |
| #include "MagickCore/magick.h" |
| #include "MagickCore/memory_.h" |
| #include "MagickCore/monitor.h" |
| #include "MagickCore/monitor-private.h" |
| #include "MagickCore/pixel-accessor.h" |
| #include "MagickCore/quantum-private.h" |
| #include "MagickCore/static.h" |
| #include "MagickCore/string_.h" |
| #include "MagickCore/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(i,set) SetPixelIndex(image,(Quantum) ((set) != 0 ? \ |
| (size_t) GetPixelIndex(image,q) | (one << (size_t) (i)) : \ |
| (size_t) GetPixelIndex(image,q) & ~(one << (size_t) (i))),q) |
| |
| Image |
| *image, |
| *watermark; |
| |
| ImageInfo |
| *read_info; |
| |
| int |
| c; |
| |
| MagickBooleanType |
| status; |
| |
| PixelInfo |
| pixel; |
| |
| register Quantum |
| *q; |
| |
| register 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,exception); |
| 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((Image *) NULL); |
| watermark->depth=MAGICKCORE_QUANTUM_DEPTH; |
| if (AcquireImageColormap(image,MaxColormapSize,exception) == MagickFalse) |
| ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed"); |
| if (image_info->ping != MagickFalse) |
| { |
| (void) CloseBlob(image); |
| return(GetFirstImageInList(image)); |
| } |
| status=SetImageExtent(image,image->columns,image->rows,exception); |
| if (status == MagickFalse) |
| return(DestroyImageList(image)); |
| for (y=0; y < (ssize_t) image->rows; y++) |
| { |
| q=QueueAuthenticPixels(image,0,y,image->columns,1,exception); |
| if (q == (Quantum *) NULL) |
| break; |
| for (x=0; x < (ssize_t) image->columns; x++) |
| { |
| SetPixelIndex(image,0,q); |
| q+=GetPixelChannels(image); |
| } |
| if (SyncAuthenticPixels(image,exception) == MagickFalse) |
| break; |
| } |
| /* |
| 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) GetOneVirtualPixelInfo(watermark,UndefinedVirtualPixelMethod, |
| k % (ssize_t) watermark->columns,k/(ssize_t) watermark->columns, |
| &pixel,exception); |
| q=GetAuthenticPixels(image,x,y,1,1,exception); |
| if (q == (Quantum *) NULL) |
| break; |
| switch (c) |
| { |
| case 0: |
| { |
| SetBit(i,GetBit(pixel.red,j)); |
| break; |
| } |
| case 1: |
| { |
| SetBit(i,GetBit(pixel.green,j)); |
| break; |
| } |
| case 2: |
| { |
| SetBit(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,exception); |
| 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=AcquireMagickInfo("STEGANO","STEGANO","Steganographic image"); |
| entry->decoder=(DecodeImageHandler *) ReadSTEGANOImage; |
| entry->format_type=ImplicitFormatType; |
| (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"); |
| } |
