coders/mac.c

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%                                                                             %
%                            M   M   AAA    CCCC                              %
%                            MM MM  A   A  C                                  %
%                            M M M  AAAAA  C                                  %
%                            M   M  A   A  C                                  %
%                            M   M  A   A   CCCC                              %
%                                                                             %
%                                                                             %
%                         Read MacPaint Image Format                          %
%                                                                             %
%                              Software Design                                %
%                                   Cristy                                    %
%                                 July 1992                                   %
%                                                                             %
%                                                                             %
%  Copyright 1999-2014 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/colorspace.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 M A C I m a g e                                                   %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  ReadMACImage() reads an MacPaint 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 ReadMACImage method is:
%
%      Image *ReadMACImage(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 *ReadMACImage(const ImageInfo *image_info,ExceptionInfo *exception)
{
  Image
    *image;

  MagickBooleanType
    status;

  register Quantum
    *q;

  register ssize_t
    x;

  register unsigned char
    *p;

  size_t
    length;

  ssize_t
    offset,
    y;

  unsigned char
    count,
    bit,
    byte,
    *pixels;

  /*
    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,exception);
  status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
  if (status == MagickFalse)
    {
      image=DestroyImageList(image);
      return((Image *) NULL);
    }
  /*
    Read MAC X image.
  */
  length=ReadBlobLSBShort(image);
  if ((length & 0xff) != 0)
    ThrowReaderException(CorruptImageError,"CorruptImage");
  for (x=0; x < (ssize_t) 638; x++)
    if (ReadBlobByte(image) == EOF)
      ThrowReaderException(CorruptImageError,"CorruptImage");
  image->columns=576;
  image->rows=720;
  image->depth=1;
  if (AcquireImageColormap(image,2,exception) == MagickFalse)
    ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
  if (image_info->ping != MagickFalse)
    {
      (void) CloseBlob(image);
      return(GetFirstImageInList(image));
    }
  /*
    Convert MAC raster image to pixel packets.
  */
  length=(image->columns+7)/8;
  pixels=(unsigned char *) AcquireQuantumMemory(length+1,sizeof(*pixels));
  if (pixels == (unsigned char *) NULL) 
    ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
  p=pixels;
  offset=0;
  for (y=0; y < (ssize_t) image->rows; )
  {
    count=(unsigned char) ReadBlobByte(image);
    if (EOFBlob(image) != MagickFalse)
      break;
    if ((count <= 0) || (count >= 128))
      {
        byte=(unsigned char) (~ReadBlobByte(image));
        count=(~count)+2;
        while (count != 0)
        {
          *p++=byte;
          offset++;
          count--;
          if (offset >= (ssize_t) length)
            {
              q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
              if (q == (Quantum *) NULL)
                break;
              p=pixels;
              bit=0;
              byte=0;
              for (x=0; x < (ssize_t) image->columns; x++)
              {
                if (bit == 0)
                  byte=(*p++);
                SetPixelIndex(image,((byte & 0x80) != 0 ? 0x01 : 0x00),q);
                bit++;
                byte<<=1;
                if (bit == 8)
                  bit=0;
                q+=GetPixelChannels(image);
              }
              if (SyncAuthenticPixels(image,exception) == MagickFalse)
                break;
              offset=0;
              p=pixels;
              y++;
            }
        }
        continue;
      }
    count++;
    while (count != 0)
    {
      byte=(unsigned char) (~ReadBlobByte(image));
      *p++=byte;
      offset++;
      count--;
      if (offset >= (ssize_t) length)
        {
          q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
          if (q == (Quantum *) NULL)
            break;
          p=pixels;
          bit=0;
          byte=0;
          for (x=0; x < (ssize_t) image->columns; x++)
          {
            if (bit == 0)
              byte=(*p++);
            SetPixelIndex(image,((byte & 0x80) != 0 ? 0x01 : 0x00),q);
            bit++;
            byte<<=1;
            if (bit == 8)
              bit=0;
            q+=GetPixelChannels(image);
          }
          if (SyncAuthenticPixels(image,exception) == MagickFalse)
            break;
          offset=0;
          p=pixels;
          y++;
        }
    }
  }
  pixels=(unsigned char *) RelinquishMagickMemory(pixels);
  (void) SyncImage(image,exception);
  (void) CloseBlob(image);
  return(GetFirstImageInList(image));
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   R e g i s t e r M A C I m a g e                                           %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  RegisterMACImage() adds attributes for the MAC X 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 RegisterMACImage method is:
%
%      size_t RegisterMACImage(void)
%
*/
ModuleExport size_t RegisterMACImage(void)
{
  MagickInfo
    *entry;

  entry=SetMagickInfo("MAC");
  entry->decoder=(DecodeImageHandler *) ReadMACImage;
  entry->description=ConstantString("MAC Paint");
  entry->module=ConstantString("MAC");
  (void) RegisterMagickInfo(entry);
  return(MagickImageCoderSignature);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   U n r e g i s t e r M A C I m a g e                                       %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  UnregisterMACImage() removes format registrations made by the
%  MAC module from the list of supported formats.
%
%  The format of the UnregisterMACImage method is:
%
%      UnregisterMACImage(void)
%
*/
ModuleExport void UnregisterMACImage(void)
{
  (void) UnregisterMagickInfo("MAC");
}