C++ AppendImageToList函数代码示例

/*
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%   S p l i c e I m a g e I n t o L i s t                                     %
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%
%  SpliceImageIntoList() removes 'length' images from the list and replaces
%  them with the specified splice. Removed images are returned.
%
%  The format of the SpliceImageIntoList method is:
%
%      SpliceImageIntoList(Image **images,const unsigned long,
%        const Image *splice)
%
%  A description of each parameter follows:
%
%    o images: the image list.
%
%    o length: the length of the image list to remove.
%
%    o splice: Replace the removed image list with this list.
%
*/
MagickExport Image *SpliceImageIntoList(Image **images,
  const unsigned long length,const Image *splice)
{
  Image
    *image,
    *split;

  register unsigned long
    i;

  assert(images != (Image **) NULL);
  assert(splice != (Image *) NULL);
  assert(splice->signature == MagickSignature);
  if ((*images) == (Image *) NULL)
    return((Image *) NULL);
  assert((*images)->signature == MagickSignature);
  if ((*images)->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
      (*images)->filename);
  split=SplitImageList(*images);
  AppendImageToList(images,splice);
  image=(Image *) NULL;
  for (i=0; (i < length) && (split != (Image *) NULL); i++)
    AppendImageToList(&image,RemoveImageFromList(&split));
  AppendImageToList(images,split);
  return(image);
}

/*
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%     S e p a r a t e I m a g e s                                             %
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%
%  SeparateImages() returns a separate grayscale image for each channel
%  specified.
%
%  The format of the SeparateImages method is:
%
%      Image *SeparateImages(const Image *image,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o exception: return any errors or warnings in this structure.
%
*/
MagickExport Image *SeparateImages(const Image *image,ExceptionInfo *exception)
{
  Image
    *images,
    *separate_image;

  register ssize_t
    i;

  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  images=NewImageList();
  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
  {
    PixelChannel channel=GetPixelChannelChannel(image,i);
    PixelTrait traits=GetPixelChannelTraits(image,channel);
    if ((traits == UndefinedPixelTrait) ||
        ((traits & UpdatePixelTrait) == 0))
      continue;
    separate_image=SeparateImage(image,(ChannelType) (1 << channel),exception);
    if (separate_image != (Image *) NULL)
      AppendImageToList(&images,separate_image);
  }
  if (images == (Image *) NULL)
    images=SeparateImage(image,UndefinedChannel,exception);
  return(images);
}

Image *AutoResizeImage(const Image *image,const char *option,
  MagickOffsetType *count,ExceptionInfo *exception)
{
  #define MAX_SIZES 16

  char
    *q;

  const char
    *p;

  Image
    *resized,
    *images;

  register ssize_t
    i;

  size_t
    sizes[MAX_SIZES]={256,192,128,96,64,48,40,32,24,16};

  images=NULL;
  *count=0;
  i=0;
  p=option;
  while (*p != '\0' && i < MAX_SIZES)
  {
    size_t
      size;

    while ((isspace((int) ((unsigned char) *p)) != 0))
      p++;

    size=(size_t)strtol(p,&q,10);
    if ((p == q) || (size < 16) || (size > 256))
      return((Image *) NULL);

    p=q;
    sizes[i++]=size;

    while ((isspace((int) ((unsigned char) *p)) != 0) || (*p == ','))
      p++;
  }

  if (i==0)
    i=10;
  *count=i;
  for (i=0; i < *count; i++)
  {
    resized=ResizeImage(image,sizes[i],sizes[i],image->filter,exception);
    if (resized == (Image *) NULL)
      return(DestroyImageList(images));

    if (images == (Image *) NULL)
      images=resized;
    else
      AppendImageToList(&images,resized);
  }
  return(images);
}

/**
 * Convert an array of Image *s to an ImageMagick scene sequence (i.e. a
 * doubly-linked list of Images).
 *
 * No Ruby usage (internal function)
 *
 * @param imagelist the imagelist
 * @return a pointer to the head of the scene sequence list
 * @see rm_imagelist_from_images
 */
static Image *
images_from_imagelist(VALUE imagelist)
{
    long x, len;
    Image *head = NULL;
    VALUE images, t;

    len = check_imagelist_length(imagelist);

    images = rb_iv_get(imagelist, "@images");
    for (x = 0; x < len; x++)
    {
        Image *image;

        t = rb_ary_entry(images, x);
        image = rm_check_destroyed(t);
        // avoid a loop in this linked imagelist, issue #202
        if (head == image || GetPreviousImageInList(image) != NULL)
        {
            image = rm_clone_image(image);
        }
        AppendImageToList(&head, image);
    }

    RB_GC_GUARD(images);
    RB_GC_GUARD(t);

    return head;
}

/*
    Extern:     images_from_imagelist
    Purpose:    Convert an array of Image *s to an ImageMagick scene
                sequence (i.e. a doubly-linked list of Images)
    Returns:    a pointer to the head of the scene sequence list
*/
static Image *
images_from_imagelist(VALUE imagelist)
{
    long x, len;
    Image *head = NULL;
    volatile VALUE images, t;

    len = imagelist_length(imagelist);
    if (len == 0)
    {
        rb_raise(rb_eArgError, "no images in this image list");
    }

    images = rb_iv_get(imagelist, "@images");
    for (x = 0; x < len; x++)
    {
        Image *image;

        t = rb_ary_entry(images, x);
        image = rm_check_destroyed(t);
        AppendImageToList(&head, image);
    }

    return head;
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%   I n s e r t I m a g e I n L i s t                                         %
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  InsertImageInList() inserts the second image or image list into the first
%  image list immediatally after the image pointed to.  The given image list
%  pointer is unchanged unless previously empty.
%
%  The format of the InsertImageInList method is:
%
%      InsertImageInList(Image **images,Image *image)
%
%  A description of each parameter follows:
%
%    o images: the image list to insert into.
%
%    o image: the image list to insert.
%
*/
MagickExport void InsertImageInList(Image **images,Image *image)
{
  Image
    *split;

  assert(images != (Image **) NULL);
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  if ((*images) == (Image *) NULL)
    return;
  assert((*images)->signature == MagickSignature);
  split=SplitImageList(*images);
  AppendImageToList(images,image);
  AppendImageToList(images,split);
}

/*
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%                                                                             %
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%   P i n g I m a g e s                                                       %
%                                                                             %
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%
%  PingImages() pings one or more images and returns them as an image list.
%
%  The format of the PingImage method is:
%
%      Image *PingImages(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.
%
*/
MagickExport Image *PingImages(const ImageInfo *image_info,
  ExceptionInfo *exception)
{
  char
    filename[MaxTextExtent];

  Image
    *image,
    *images;

  ImageInfo
    *read_info;

  /*
    Ping image list from a file.
  */
  assert(image_info != (ImageInfo *) NULL);
  assert(image_info->signature == MagickSignature);
  if (image_info->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
      image_info->filename);
  assert(exception != (ExceptionInfo *) NULL);
  (void) InterpretImageFilename(image_info,(Image *) NULL,image_info->filename,
    (int) image_info->scene,filename,exception);
  if (LocaleCompare(filename,image_info->filename) != 0)
    {
      ExceptionInfo
        *sans;

      ssize_t
        extent,
        scene;

      /*
        Images of the form image-%d.png[1-5].
      */
      read_info=CloneImageInfo(image_info);
      sans=AcquireExceptionInfo();
      (void) SetImageInfo(read_info,0,sans);
      sans=DestroyExceptionInfo(sans);
      (void) CopyMagickString(filename,read_info->filename,MaxTextExtent);
      images=NewImageList();
      extent=(ssize_t) (read_info->scene+read_info->number_scenes);
      for (scene=(ssize_t) read_info->scene; scene < (ssize_t) extent; scene++)
      {
        (void) InterpretImageFilename(image_info,(Image *) NULL,filename,(int)
          scene,read_info->filename,exception);
        image=PingImage(read_info,exception);
        if (image == (Image *) NULL)
          continue;
        AppendImageToList(&images,image);
      }
      read_info=DestroyImageInfo(read_info);
      return(images);
    }
  return(PingImage(image_info,exception));
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     S e p a r a t e I m a g e s                                             %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  SeparateImages() returns a separate grayscale image for each channel
%  specified.
%
%  The format of the SeparateImages method is:
%
%      MagickBooleanType SeparateImages(const Image *image,
%        const ChannelType channel,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the image.
%
%    o channel: Identify which channels to extract: RedChannel, GreenChannel,
%      BlueChannel, OpacityChannel, CyanChannel, MagentaChannel,
%      YellowChannel, or BlackChannel.
%
%    o exception: return any errors or warnings in this structure.
%
*/
MagickExport Image *SeparateImages(const Image *image,const ChannelType channel,
  ExceptionInfo *exception)
{
  Image
    *images,
    *separate_image;

  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  images=NewImageList();
  if ((channel & RedChannel) != 0)
    {
      separate_image=CloneImage(image,0,0,MagickTrue,exception);
      (void) SeparateImageChannel(separate_image,RedChannel);
      AppendImageToList(&images,separate_image);
    }
  if ((channel & GreenChannel) != 0)
    {
      separate_image=CloneImage(image,0,0,MagickTrue,exception);
      (void) SeparateImageChannel(separate_image,GreenChannel);
      AppendImageToList(&images,separate_image);
    }
  if ((channel & BlueChannel) != 0)
    {
      separate_image=CloneImage(image,0,0,MagickTrue,exception);
      (void) SeparateImageChannel(separate_image,BlueChannel);
      AppendImageToList(&images,separate_image);
    }
  if (((channel & BlackChannel) != 0) && (image->colorspace == CMYKColorspace))
    {
      separate_image=CloneImage(image,0,0,MagickTrue,exception);
      (void) SeparateImageChannel(separate_image,BlackChannel);
      AppendImageToList(&images,separate_image);
    }
  if ((channel & AlphaChannel) != 0)
    {
      separate_image=CloneImage(image,0,0,MagickTrue,exception);
      (void) SeparateImageChannel(separate_image,TrueAlphaChannel);
      AppendImageToList(&images,separate_image);
    }
  return(images);
}

/**
 * Clone a list of images, handle errors.
 *
 * No Ruby usage (internal function)
 *
 * @param images the images
 * @return a new array of images
 */
static Image *
clone_imagelist(Image *images)
{
    Image *new_imagelist = NULL, *image, *clone;
    ExceptionInfo *exception;

    exception = AcquireExceptionInfo();

    image = GetFirstImageInList(images);
    while (image)
    {
        clone = CloneImage(image, 0, 0, MagickTrue, exception);
        rm_check_exception(exception, new_imagelist, DestroyOnError);
        AppendImageToList(&new_imagelist, clone);
        image = GetNextImageInList(image);
    }

    (void) DestroyExceptionInfo(exception);
    return new_imagelist;
}

/*
    Extern:     images_from_imagelist
    Purpose:    Convert an array of Image *s to an ImageMagick scene
                sequence (i.e. a doubly-linked list of Images)
    Returns:    a pointer to the head of the scene sequence list
*/
static Image *
images_from_imagelist(VALUE imagelist)
{
    long x, len;
    Image *head = NULL;
    volatile VALUE images, t;

    len = check_imagelist_length(imagelist);

    images = rb_iv_get(imagelist, "@images");
    for (x = 0; x < len; x++)
    {
        Image *image;

        t = rb_ary_entry(images, x);
        image = rm_check_destroyed(t);
        AppendImageToList(&head, image);
    }

    return head;
}

static int load_images(LogoPrivateData *pd)
{
    Image         *timg;
    Image         *nimg;

    pd->images = GetFirstImageInList(pd->magick.image);
    nimg = NewImageList();

    while (pd->images != (Image *)NULL) {
        if (pd->flip) {
            timg = FlipImage(pd->images, 
                             &pd->magick.exception_info);
            if (timg == NULL) {
                CatchException(&pd->magick.exception_info);
                return TC_ERROR;
            }
            AppendImageToList(&nimg, timg);
        }

        pd->images = GetNextImageInList(pd->images);
        pd->nr_of_images++;
    }

    // check for memleaks;
    //DestroyImageList(image);
    if (pd->flip) {
        /* DANGEROUS!!! */
        pd->magick.image = nimg;
    }

    /* for running through image sequence */
    /* DANGEROUS!!! */
    pd->images = pd->magick.image;

    return TC_OK;
}

MagickExport Image *ForwardFourierTransformImage(const Image *image,
  const MagickBooleanType modulus,ExceptionInfo *exception)
{
  Image
    *fourier_image;

  fourier_image=NewImageList();
#if !defined(MAGICKCORE_FFTW_DELEGATE)
  (void) modulus;
  (void) ThrowMagickException(exception,GetMagickModule(),
    MissingDelegateWarning,"DelegateLibrarySupportNotBuiltIn","`%s' (FFTW)",
    image->filename);
#else
  {
    Image
      *magnitude_image;

    size_t
      extent,
      width;

    width=image->columns;
    if ((image->columns != image->rows) || ((image->columns % 2) != 0) ||
        ((image->rows % 2) != 0))
      {
        extent=image->columns < image->rows ? image->rows : image->columns;
        width=(extent & 0x01) == 1 ? extent+1UL : extent;
      }
    magnitude_image=CloneImage(image,width,width,MagickFalse,exception);
    if (magnitude_image != (Image *) NULL)
      {
        Image
          *phase_image;

        magnitude_image->storage_class=DirectClass;
        magnitude_image->depth=32UL;
        phase_image=CloneImage(image,width,width,MagickFalse,exception);
        if (phase_image == (Image *) NULL)
          magnitude_image=DestroyImage(magnitude_image);
        else
          {
            MagickBooleanType
              is_gray,
              status;

            phase_image->storage_class=DirectClass;
            phase_image->depth=32UL;
            AppendImageToList(&fourier_image,magnitude_image);
            AppendImageToList(&fourier_image,phase_image);
            status=MagickTrue;
            is_gray=IsGrayImage(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
            #pragma omp parallel sections
#endif
            {
#if defined(MAGICKCORE_OPENMP_SUPPORT)
              #pragma omp section
#endif
              {
                MagickBooleanType
                  thread_status;

                if (is_gray != MagickFalse)
                  thread_status=ForwardFourierTransformChannel(image,
                    GrayChannels,modulus,fourier_image,exception);
                else
                  thread_status=ForwardFourierTransformChannel(image,
                    RedChannel,modulus,fourier_image,exception);
                if (thread_status == MagickFalse)
                  status=thread_status;
              }
#if defined(MAGICKCORE_OPENMP_SUPPORT)
              #pragma omp section
#endif
              {
                MagickBooleanType
                  thread_status;

                thread_status=MagickTrue;
                if (is_gray == MagickFalse)
                  thread_status=ForwardFourierTransformChannel(image,
                    GreenChannel,modulus,fourier_image,exception);
                if (thread_status == MagickFalse)
                  status=thread_status;
              }
#if defined(MAGICKCORE_OPENMP_SUPPORT)
              #pragma omp section
#endif
              {
                MagickBooleanType
                  thread_status;

                thread_status=MagickTrue;
                if (is_gray == MagickFalse)
                  thread_status=ForwardFourierTransformChannel(image,
                    BlueChannel,modulus,fourier_image,exception);
                if (thread_status == MagickFalse)
                  status=thread_status;
              }
#if defined(MAGICKCORE_OPENMP_SUPPORT)
//.........这里部分代码省略.........

//.........这里部分代码省略.........

    offset=SeekBlob(image,(MagickOffsetType) jnx_level_info[i].offset,SEEK_SET);
    if (offset != (MagickOffsetType) jnx_level_info[i].offset)
      continue;
    for (j=0; j < (ssize_t) jnx_level_info[i].count; j++)
    {
      Image
        *tile_image;

      ImageInfo
        *read_info;

      int
        tile_offset;

      MagickOffsetType
        restore_offset;

      PointInfo
        northeast,
        southwest;

      ssize_t
        count;

      unsigned char
        *blob;

      unsigned int
        tile_length;

      northeast.x=180.0*((int) ReadBlobLSBLong(image))/0x7fffffff;
      northeast.y=180.0*((int) ReadBlobLSBLong(image))/0x7fffffff;
      southwest.x=180.0*((int) ReadBlobLSBLong(image))/0x7fffffff;
      southwest.y=180.0*((int) ReadBlobLSBLong(image))/0x7fffffff;
      (void) ReadBlobLSBShort(image); /* width */
      (void) ReadBlobLSBShort(image); /* height */
      tile_length=ReadBlobLSBLong(image);
      tile_offset=(int) ReadBlobLSBLong(image);
      if (tile_offset == -1)
        continue;
      restore_offset=TellBlob(image);
      if (restore_offset < 0)
        continue;
      offset=SeekBlob(image,(MagickOffsetType) tile_offset,SEEK_SET);
      if (offset != (MagickOffsetType) tile_offset)
        continue;
      /*
        Read a tile.
      */
      blob=(unsigned char *) AcquireQuantumMemory((size_t) tile_length+2,
        sizeof(*blob));
      if (blob == (unsigned char *) NULL)
        {
          if (images != (Image *) NULL)
            images=DestroyImageList(images);
          ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
        }
      blob[0]=0xFF;
      blob[1]=0xD8;
      count=ReadBlob(image,tile_length,blob+2);
      if (count != (ssize_t) tile_length)
        {
          if (images != (Image *) NULL)
            images=DestroyImageList(images);
          blob=(unsigned char *) RelinquishMagickMemory(blob);
          ThrowReaderException(CorruptImageError,"UnexpectedEndOfFile");
        }
      read_info=CloneImageInfo(image_info);
      (void) CopyMagickString(read_info->magick,"JPEG",MagickPathExtent);
      tile_image=BlobToImage(read_info,blob,tile_length+2,exception);
      read_info=DestroyImageInfo(read_info);
      blob=(unsigned char *) RelinquishMagickMemory(blob);
      offset=SeekBlob(image,restore_offset,SEEK_SET);
      if (tile_image == (Image *) NULL)
        continue;
      (void) CopyMagickString(tile_image->magick,image->magick,MagickPathExtent);
      (void) FormatImageProperty(tile_image,"jnx:northeast","%.20g,%.20g",
        northeast.x,northeast.y);
      (void) FormatImageProperty(tile_image,"jnx:southwest","%.20g,%.20g",
        southwest.x,southwest.y);
      AppendImageToList(&images,tile_image);
    }
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

        proceed=SetImageProgress(image,LoadImageTag,(MagickOffsetType) i,
          (MagickSizeType) jnx_info.levels);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  (void) CloseBlob(image);
  image=DestroyImage(image);
  if (images == (Image *) NULL)
    return((Image *) NULL);
  return(GetFirstImageInList(images));
}

//.........这里部分代码省略.........
    difference_image=CompareImageChannels(image,reconstruct_image,channels,
      metric,&distortion,exception);
  else
    if (similarity_image == (Image *) NULL)
      ThrowCompareException(OptionError,"ImageWidthsOrHeightsDiffer",
        image->filename)
    else
      {
        Image
          *composite_image;

        /*
          Determine if reconstructed image is a subimage of the image.
        */
        composite_image=CloneImage(image,0,0,MagickTrue,exception);
        if (composite_image == (Image *) NULL)
          difference_image=CompareImageChannels(image,reconstruct_image,
            channels,metric,&distortion,exception);
        else
          {
            (void) CompositeImage(composite_image,CopyCompositeOp,
              reconstruct_image,offset.x,offset.y);
            difference_image=CompareImageChannels(image,composite_image,
              channels,metric,&distortion,exception);
            if (difference_image != (Image *) NULL)
              {
                difference_image->page.x=offset.x;
                difference_image->page.y=offset.y;
              }
            composite_image=DestroyImage(composite_image);
          }
        if (difference_image != (Image *) NULL)
          {
            AppendImageToList(&difference_image,similarity_image);
            similarity_image=(Image *) NULL;
          }
      }
  if (difference_image == (Image *) NULL)
    status=0;
  else
    {
      if (image_info->verbose != MagickFalse)
        (void) IsImagesEqual(image,reconstruct_image);
      if (*difference_image->magick == '\0')
        (void) CopyMagickString(difference_image->magick,image->magick,
          MaxTextExtent);
      if (image_info->verbose == MagickFalse)
        {
          switch (metric)
          {
            case FuzzErrorMetric:
            case MeanAbsoluteErrorMetric:
            case MeanSquaredErrorMetric:
            case RootMeanSquaredErrorMetric:
            case PeakAbsoluteErrorMetric:
            {
              (void) FormatLocaleFile(stderr,"%g (%g)",QuantumRange*distortion,
                (double) distortion);
              if ((reconstruct_image->columns != image->columns) ||
                  (reconstruct_image->rows != image->rows))
                (void) FormatLocaleFile(stderr," @ %.20g,%.20g",(double)
                  difference_image->page.x,(double) difference_image->page.y);
              (void) FormatLocaleFile(stderr,"\n");
              break;
            }
            case AbsoluteErrorMetric:

//.........这里部分代码省略.........

    RGBTRIPLE
      *p;

    ssize_t
      y;

    assert(image_info != (const ImageInfo *) NULL);
    i=0;
    device.cb = sizeof(device);
    image=(Image *) NULL;
    while(EnumDisplayDevices(NULL,i,&device,0) && ++i)
    {
      if ((device.StateFlags & DISPLAY_DEVICE_ACTIVE) != DISPLAY_DEVICE_ACTIVE)
        continue;

      hDC=CreateDC(device.DeviceName,device.DeviceName,NULL,NULL);
      if (hDC == (HDC) NULL)
        ThrowReaderException(CoderError,"UnableToCreateDC");

      screen=AcquireImage(image_info);
      screen->columns=(size_t) GetDeviceCaps(hDC,HORZRES);
      screen->rows=(size_t) GetDeviceCaps(hDC,VERTRES);
      screen->storage_class=DirectClass;
      status=SetImageExtent(screen,screen->columns,screen->rows);
      if (status == MagickFalse)
        {
          InheritException(exception,&image->exception);
          return(DestroyImageList(image));
        }
      if (image == (Image *) NULL)
        image=screen;
      else
        AppendImageToList(&image,screen);

      bitmapDC=CreateCompatibleDC(hDC);
      if (bitmapDC == (HDC) NULL)
        {
          DeleteDC(hDC);
          ThrowReaderException(CoderError,"UnableToCreateDC");
        }
      (void) ResetMagickMemory(&bmi,0,sizeof(BITMAPINFO));
      bmi.bmiHeader.biSize=sizeof(BITMAPINFOHEADER);
      bmi.bmiHeader.biWidth=(LONG) screen->columns;
      bmi.bmiHeader.biHeight=(-1)*(LONG) screen->rows;
      bmi.bmiHeader.biPlanes=1;
      bmi.bmiHeader.biBitCount=24;
      bmi.bmiHeader.biCompression=BI_RGB;
      bitmap=CreateDIBSection(hDC,&bmi,DIB_RGB_COLORS,(void **) &p,NULL,0);
      if (bitmap == (HBITMAP) NULL)
        {
          DeleteDC(hDC);
          DeleteDC(bitmapDC);
          ThrowReaderException(CoderError,"UnableToCreateBitmap");
        }
      bitmapOld=(HBITMAP) SelectObject(bitmapDC,bitmap);
      if (bitmapOld == (HBITMAP) NULL)
        {
          DeleteDC(hDC);
          DeleteDC(bitmapDC);
          DeleteObject(bitmap);
          ThrowReaderException(CoderError,"UnableToCreateBitmap");
        }
      BitBlt(bitmapDC,0,0,(int) screen->columns,(int) screen->rows,hDC,0,0,
        SRCCOPY);
      (void) SelectObject(bitmapDC,bitmapOld);