root / ImageMagick / branches / ImageMagick-6.3.5 / magick / fx.c

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%                                 FFFFF  X   X                                %
%                                 F       X X                                 %
%                                 FFF      X                                  %
%                                 F       X X                                 %
%                                 F      X   X                                %
%                                                                             %
%                                                                             %
%                  ImageMagick Image Special Effects Methods                  %
%                                                                             %
%                               Software Design                               %
%                                 John Cristy                                 %
%                                 October 1996                                %
%                                                                             %
%                                                                             %
%  Copyright 1999-2007 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 "magick/studio.h"
#include "magick/annotate.h"
#include "magick/cache.h"
#include "magick/cache-view.h"
#include "magick/color.h"
#include "magick/color-private.h"
#include "magick/composite.h"
#include "magick/decorate.h"
#include "magick/draw.h"
#include "magick/effect.h"
#include "magick/enhance.h"
#include "magick/exception.h"
#include "magick/exception-private.h"
#include "magick/fx.h"
#include "magick/fx-private.h"
#include "magick/gem.h"
#include "magick/geometry.h"
#include "magick/list.h"
#include "magick/log.h"
#include "magick/image.h"
#include "magick/image-private.h"
#include "magick/memory_.h"
#include "magick/monitor.h"
#include "magick/option.h"
#include "magick/pixel-private.h"
#include "magick/property.h"
#include "magick/quantum.h"
#include "magick/random_.h"
#include "magick/resample.h"
#include "magick/resize.h"
#include "magick/shear.h"
#include "magick/splay-tree.h"
#include "magick/statistic.h"
#include "magick/string_.h"
#include "magick/transform.h"
#include "magick/utility.h"

/*
  Define declarations.
*/
#define LeftShiftOperator 0xf5
#define RightShiftOperator 0xf6
#define LessThanEqualOperator 0xf7
#define GreaterThanEqualOperator 0xf8
#define EqualOperator 0xf9
#define NotEqualOperator 0xfa
#define LogicalAndOperator 0xfb
#define LogicalOrOperator 0xfc

struct _FxInfo
{
  const Image
    *images;

  MagickBooleanType
    matte;

  char
    *expression;

  SplayTreeInfo
    *colors,
    *symbols;

  ExceptionInfo
    *exception;
};

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
+   A c q u i r e F x I n f o                                                 %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  AcquireFxInfo() allocates the FxInfo structure.
%
%  The format of the AcquireFxInfo method is:
%
%      FxInfo *AcquireFxInfo(Image *image,const char *expression)
%  A description of each parameter follows:
%
%    o image: The image.
%
%    o expression: The expression.
%
*/
MagickExport FxInfo *AcquireFxInfo(const Image *image,const char *expression)
{
  char
    fx_op[2];

  FxInfo
    *fx_info;

  fx_info=(FxInfo *) AcquireMagickMemory(sizeof(*fx_info));
  if (fx_info == (FxInfo *) NULL)
    ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
  (void) ResetMagickMemory(fx_info,0,sizeof(*fx_info));
  fx_info->exception=AcquireExceptionInfo();
  fx_info->images=image;
  fx_info->matte=image->matte;
  fx_info->colors=NewSplayTree(CompareSplayTreeString,RelinquishMagickMemory,
    RelinquishMagickMemory);
  fx_info->symbols=NewSplayTree(CompareSplayTreeString,RelinquishMagickMemory,
    RelinquishMagickMemory);
  if (*expression != '@')
    fx_info->expression=AcquireString(expression);
  else
    fx_info->expression=FileToString(expression+1,~0,fx_info->exception);
  (void) SubstituteString(&fx_info->expression," ","");
  fx_op[1]='\0';
  *fx_op=(char) LeftShiftOperator;
  (void) SubstituteString(&fx_info->expression,"<<",fx_op);
  *fx_op=(char) RightShiftOperator;
  (void) SubstituteString(&fx_info->expression,">>",fx_op);
  *fx_op=(char) LessThanEqualOperator;
  (void) SubstituteString(&fx_info->expression,"<=",fx_op);
  *fx_op=(char) GreaterThanEqualOperator;
  (void) SubstituteString(&fx_info->expression,">=",fx_op);
  *fx_op=(char) EqualOperator;
  (void) SubstituteString(&fx_info->expression,"==",fx_op);
  *fx_op=(char) NotEqualOperator;
  (void) SubstituteString(&fx_info->expression,"!=",fx_op);
  *fx_op=(char) LogicalAndOperator;
  (void) SubstituteString(&fx_info->expression,"&&",fx_op);
  *fx_op=(char) LogicalOrOperator;
  (void) SubstituteString(&fx_info->expression,"||",fx_op);
  return(fx_info);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     C h a r c o a l I m a g e                                               %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  CharcoalImage() creates a new image that is a copy of an existing one with
%  the edge highlighted.  It allocates the memory necessary for the new Image
%  structure and returns a pointer to the new image.
%
%  The format of the CharcoalImage method is:
%
%      Image *CharcoalImage(const Image *image,const double radius,
%        const double sigma,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: The image.
%
%    o radius: the radius of the pixel neighborhood.
%
%    o sigma: The standard deviation of the Gaussian, in pixels.
%
%    o exception: Return any errors or warnings in this structure.
%
*/
MagickExport Image *CharcoalImage(const Image *image,const double radius,
  const double sigma,ExceptionInfo *exception)
{
  Image
    *charcoal_image,
    *clone_image,
    *edge_image;

  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  clone_image=CloneImage(image,0,0,MagickTrue,exception);
  if (clone_image == (Image *) NULL)
    return((Image *) NULL);
  (void) SetImageType(clone_image,GrayscaleType);
  edge_image=EdgeImage(clone_image,radius,exception);
  clone_image=DestroyImage(clone_image);
  if (edge_image == (Image *) NULL)
    return((Image *) NULL);
  charcoal_image=BlurImage(edge_image,radius,sigma,exception);
  edge_image=DestroyImage(edge_image);
  if (charcoal_image == (Image *) NULL)
    return((Image *) NULL);
  (void) NormalizeImage(charcoal_image);
  (void) NegateImage(charcoal_image,MagickFalse);
  (void) SetImageType(charcoal_image,GrayscaleType);
  return(charcoal_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     C o l o r i z e I m a g e                                               %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  ColorizeImage() blends the fill color with each pixel in the image.
%  A percentage blend is specified with opacity.  Control the application
%  of different color components by specifying a different percentage for
%  each component (e.g. 90/100/10 is 90% red, 100% green, and 10% blue).
%
%  The format of the ColorizeImage method is:
%
%      Image *ColorizeImage(const Image *image,const char *opacity,
%        const PixelPacket colorize,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: The image.
%
%    o opacity:  A character string indicating the level of opacity as a
%      percentage.
%
%    o colorize: A color value.
%
%    o exception: Return any errors or warnings in this structure.
%
*/
MagickExport Image *ColorizeImage(const Image *image,const char *opacity,
  const PixelPacket colorize,ExceptionInfo *exception)
{
#define ColorizeImageTag  "Colorize/Image"

  GeometryInfo
    geometry_info;

  Image
    *colorize_image;

  long
    y;

  MagickBooleanType
    status;

  MagickPixelPacket
    pixel;

  MagickStatusType
    flags;

  register const PixelPacket
    *p;

  register long
    x;

  register PixelPacket
    *q;

  /*
    Allocate colorized image.
  */
  assert(image != (const Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  colorize_image=CloneImage(image,0,0,MagickTrue,exception);
  if (colorize_image == (Image *) NULL)
    return((Image *) NULL);
  if (SetImageStorageClass(colorize_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&colorize_image->exception);
      colorize_image=DestroyImage(colorize_image);
      return((Image *) NULL);
    }
  if (opacity == (const char *) NULL)
    return(colorize_image);
  /*
    Determine RGB values of the pen color.
  */
  flags=ParseGeometry(opacity,&geometry_info);
  pixel.red=geometry_info.rho;
  if ((flags & SigmaValue) != 0)
    pixel.green=geometry_info.sigma;
  else
    pixel.green=pixel.red;
  if ((flags & XiValue) != 0)
    pixel.blue=geometry_info.xi;
  else
    pixel.blue=pixel.red;
  if ((flags & PsiValue) != 0)
    pixel.opacity=geometry_info.psi;
  else
    pixel.opacity=(MagickRealType) OpaqueOpacity;
  /*
    Colorize DirectClass image.
  */
  for (y=0; y < (long) image->rows; y++)
  {
    p=AcquireImagePixels(image,0,y,image->columns,1,exception);
    q=GetImagePixels(colorize_image,0,y,colorize_image->columns,1);
    if ((p == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
      break;
    for (x=0; x < (long) image->columns; x++)
    {
      q->red=(Quantum) ((p->red*(100.0-pixel.red)+
        colorize.red*pixel.red)/100.0);
      q->green=(Quantum) ((p->green*(100.0-pixel.green)+
        colorize.green*pixel.green)/100.0);
      q->blue=(Quantum) ((p->blue*(100.0-pixel.blue)+
        colorize.blue*pixel.blue)/100.0);
      q->opacity=(Quantum) ((p->opacity*(100.0-pixel.opacity)+
        colorize.opacity*pixel.opacity)/100.0);
      p++;
      q++;
    }
    if (SyncImagePixels(colorize_image) == MagickFalse)
      break;
    if ((image->progress_monitor != (MagickProgressMonitor) NULL) &&
        (QuantumTick(y,image->rows) != MagickFalse))
      {
        status=image->progress_monitor(ColorizeImageTag,y,image->rows,
          image->client_data);
        if (status == MagickFalse)
          break;
      }
  }
  return(colorize_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     C o n v o l v e I m a g e                                               %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  ConvolveImage() applies a custom convolution kernel to the image.
%
%  The format of the ConvolveImage method is:
%
%      Image *ConvolveImage(const Image *image,const unsigned long order,
%        const double *kernel,ExceptionInfo *exception)
%      Image *ConvolveImageChannel(const Image *image,const ChannelType channel,
%        const unsigned long order,const double *kernel,
%        ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: The image.
%
%    o channel: The channel type.
%
%    o order: The number of columns and rows in the filter kernel.
%
%    o kernel: An array of double representing the convolution kernel.
%
%    o exception: Return any errors or warnings in this structure.
%
*/

MagickExport Image *ConvolveImage(const Image *image,const unsigned long order,
  const double *kernel,ExceptionInfo *exception)
{
  Image
    *convolve_image;

  convolve_image=ConvolveImageChannel(image,DefaultChannels,order,kernel,
    exception);
  return(convolve_image);
}

MagickExport Image *ConvolveImageChannel(const Image *image,
  const ChannelType channel,const unsigned long order,const double *kernel,
  ExceptionInfo *exception)
{
#define ConvolveImageTag  "Convolve/Image"

  Image
    *convolve_image;

  long
    j,
    u,
    v,
    y;

  MagickBooleanType
    status;

  MagickPixelPacket
    pixel;

  MagickRealType
    alpha,
    gamma;

  register const double
    *k;
  register const IndexPacket
    *indexes;

  register const PixelPacket
    *pixels;

  register IndexPacket
    *convolve_indexes;

  register long
    x;

  register PixelPacket
    *convolve_pixels;

  unsigned long
    width;

  /*
    Initialize convolve image attributes.
  */
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  width=order;
  if ((width % 2) == 0)
    ThrowImageException(OptionError,"KernelWidthMustBeAnOddNumber");
  convolve_image=CloneImage(image,0,0,MagickTrue,exception);
  if (convolve_image == (Image *) NULL)
    return((Image *) NULL);
  if (SetImageStorageClass(convolve_image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&convolve_image->exception);
      convolve_image=DestroyImage(convolve_image);
      return((Image *) NULL);
    }
  /*
    Convolve image.
  */
  if (image->debug != MagickFalse)
    {
      char
        format[MaxTextExtent],
        *message;

      (void) LogMagickEvent(TransformEvent,GetMagickModule(),
        "  ConvolveImage with %ldx%ld kernel:",width,width);
      message=AcquireString("");
      k=kernel;
      for (v=0; v < (long) width; v++)
      {
        *message='\0';
        (void) FormatMagickString(format,MaxTextExtent,"%ld: ",v);
        (void) ConcatenateString(&message,format);
        for (u=0; u < (long) width; u++)
        {
          (void) FormatMagickString(format,MaxTextExtent,"%+f ",*k++);
          (void) ConcatenateString(&message,format);
        }
        (void) LogMagickEvent(TransformEvent,GetMagickModule(),"%s",message);
      }
      message=DestroyString(message);
    }
  for (y=0; y < (long) convolve_image->rows; y++)
  {
    pixels=AcquireImagePixels(image,-((long) width/2L),y-(long) (width/2L),
      image->columns+width,width,exception);
    convolve_pixels=GetImagePixels(convolve_image,0,y,convolve_image->columns,
      1);
    if ((pixels == (const PixelPacket *) NULL) ||
        (convolve_pixels == (PixelPacket *) NULL))
      break;
    indexes=AcquireIndexes(image);
    convolve_indexes=GetIndexes(convolve_image);
    #pragma omp parallel for private(alpha, gamma, j, k, pixel, u, v)
    for (x=0; x < (long) convolve_image->columns; x++)
    {
      GetMagickPixelPacket(image,&pixel);
      gamma=0.0;
      k=kernel;
      j=0;
      for (v=0; v < (long) width; v++)
      {
        for (u=0; u < (long) width; u++)
        {
          alpha=1.0;
          if (((channel & OpacityChannel) != 0) &&
              (image->matte != MagickFalse))
            alpha=((MagickRealType) QuantumRange-pixels[x+u+j].opacity)/
              (MagickRealType) QuantumRange;
          if ((channel & RedChannel) != 0)
            pixel.red+=(*k)*alpha*pixels[x+u+j].red;
          if ((channel & GreenChannel) != 0)
            pixel.green+=(*k)*alpha*pixels[x+u+j].green;
          if ((channel & BlueChannel) != 0)
            pixel.blue+=(*k)*alpha*pixels[x+u+j].blue;
          if ((channel & OpacityChannel) != 0)
            pixel.opacity+=(*k)*pixels[x+u+j].opacity;
          if (((channel & IndexChannel) != 0) &&
              (image->colorspace == CMYKColorspace))
            pixel.index+=(*k)*alpha*indexes[x+u+j];
          gamma+=(*k)*alpha;
          k++;
        }
        j+=image->columns+width;
      }
      gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
      if ((channel & RedChannel) != 0)
        convolve_pixels[x].red=RoundToQuantum(gamma*pixel.red+image->bias);
      if ((channel & GreenChannel) != 0)
        convolve_pixels[x].green=RoundToQuantum(gamma*pixel.green+image->bias);
      if ((channel & BlueChannel) != 0)
        convolve_pixels[x].blue=RoundToQuantum(gamma*pixel.blue+image->bias);
      if ((channel & OpacityChannel) != 0)
        convolve_pixels[x].opacity=RoundToQuantum(pixel.opacity+image->bias);
      if (((channel & IndexChannel) != 0) &&
          (image->colorspace == CMYKColorspace))
        convolve_indexes[x]=RoundToQuantum(gamma*pixel.index+image->bias);
    }
    if (SyncImagePixels(convolve_image) == MagickFalse)
      break;
    if ((image->progress_monitor != (MagickProgressMonitor) NULL) &&
        (QuantumTick(y,image->rows) != MagickFalse))
      {
        status=image->progress_monitor(ConvolveImageTag,y,image->rows,
          image->client_data);
        if (status == MagickFalse)
          break;
      }
  }
  return(convolve_image);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
+   D e s t r o y F x I n f o                                                 %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  DestroyImageInfo() deallocates memory associated with an FxInfo structure.
%
%  The format of the DestroyImageInfo method is:
%
%      ImageInfo *DestroyImageInfo(ImageInfo *fx_info)
%
%  A description of each parameter follows:
%
%    o fx_info: The fx info.
%
*/
MagickExport FxInfo *DestroyFxInfo(FxInfo *fx_info)
{
  fx_info->exception=DestroyExceptionInfo(fx_info->exception);
  fx_info->expression=DestroyString(fx_info->expression);
  fx_info->symbols=DestroySplayTree(fx_info->symbols);
  fx_info->colors=DestroySplayTree(fx_info->colors);
  fx_info=(FxInfo *) RelinquishMagickMemory(fx_info);
  return(fx_info);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%     E v a l u a t e I m a g e                                               %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  EvaluateImage() applies a value to the image with an arithmetic, relational,
%  or logical operator to an image. Use these operations to lighten or darken
%  an image, to increase or decrease contrast in an image, or to produce the
%  "negative" of an image.
%
%  The format of the EvaluateImageChannel method is:
%
%      MagickBooleanType EvaluateImage(Image *image,
%        const MagickEvaluateOperator op,const double value,
%        ExceptionInfo *exception)
%      MagickBooleanType EvaluateImageChannel(Image *image,
%        const ChannelType channel,const MagickEvaluateOperator op,
%        const double value,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: The image.
%
%    o channel: The channel.
%
%    o op: A channel op.
%
%    o value: A value value.
%
%    o exception: Return any errors or warnings in this structure.
%
*/

static inline double MagickMax(const double x,const double y)
{
  if (x > y)
    return(x);
  return(y);
}

static inline double MagickMin(const double x,const double y)
{
  if (x < y)
    return(x);
  return(y);
}

static inline Quantum ApplyEvaluateOperator(Quantum pixel,
  const MagickEvaluateOperator op,const MagickRealType value)
{
  double
    result;

  result=0.0;
  switch(op)
  {
    case UndefinedEvaluateOperator:
      break;
    case AddEvaluateOperator:
    {
      result=pixel+value;
      break;
    }
    case AndEvaluateOperator:
    {
      result=(MagickRealType) ((unsigned long) pixel & (unsigned long)
        (value+0.5));
      break;
    }
    case DivideEvaluateOperator:
    {
      result=pixel/(value == 0.0 ? 1.0 : value);
      break;
    }
    case LeftShiftEvaluateOperator:
    {
      result=(MagickRealType) ((unsigned long) pixel << (unsigned long)
        (value+0.5));
      break;
    }
    case MaxEvaluateOperator:
    {
      result=MagickMax((double) pixel,value);
      break;
    }
    case MinEvaluateOperator:
    {
      result=MagickMin((double) pixel,value);
      break;
    }
    case MultiplyEvaluateOperator:
    {
      result=pixel*value;
      break;
    }
    case OrEvaluateOperator:
    {
      result=(MagickRealType) ((unsigned long) pixel | (unsigned long)
        (value+0.5));
      break;
    }
    case RightShiftEvaluateOperator:
    {
      result=(MagickRealType) ((unsigned long) pixel >> (unsigned long)
        (value+0.5));
      break;
    }
    case SetEvaluateOperator:
    {
      result=value;
      break;
    }
    case SubtractEvaluateOperator:
    {
      result=pixel-value;
      break;
    }
    case XorEvaluateOperator:
    {
      result=(MagickRealType) ((unsigned long) pixel ^ (unsigned long)
        (value+0.5));
      break;
    }
  }
  return(RoundToQuantum(result));
}

MagickExport MagickBooleanType EvaluateImage(Image *image,
  const MagickEvaluateOperator op,const double value,ExceptionInfo *exception)
{
  MagickBooleanType
    status;

  status=EvaluateImageChannel(image,AllChannels,op,value,exception);
  return(status);
}

MagickExport MagickBooleanType EvaluateImageChannel(Image *image,
  const ChannelType channel,const MagickEvaluateOperator op,const double value,
  ExceptionInfo *exception)
{
#define EvaluateImageTag  "Constant/Image "

  IndexPacket
    *indexes;

  long
    y;

  MagickBooleanType
    status;

  register long
    x;

  register PixelPacket
    *q;

  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  if (SetImageStorageClass(image,DirectClass) == MagickFalse)
    {
      InheritException(exception,&image->exception);
      return(MagickFalse);
    }
  for (y=0; y < (long) image->rows; y++)
  {
    q=GetImagePixels(image,0,y,image->columns,1);
    if (q == (PixelPacket *) NULL)
      break;
    indexes=GetIndexes(image);
    for (x=0; x < (long) image->columns; x++)
    {
      if ((channel & RedChannel) != 0)
        q->red=ApplyEvaluateOperator(q->red,op,value);
      if ((channel & GreenChannel) != 0)
        q->green=ApplyEvaluateOperator(q->green,op,value);
      if ((channel & BlueChannel) != 0)
        q->blue=ApplyEvaluateOperator(q->blue,op,value);
      if ((channel & OpacityChannel) != 0)
        {
          if (image->matte == MagickFalse)
            q->opacity=ApplyEvaluateOperator(q->opacity,op,value);
          else
            q->opacity=(Quantum) QuantumRange-ApplyEvaluateOperator(
              (Quantum) QuantumRange-q->opacity,op,value);
        }
      if (((channel & IndexChannel) != 0) && (indexes != (IndexPacket *) NULL))
        indexes[x]=(IndexPacket) ApplyEvaluateOperator(indexes[x],op,value);
      q++;
    }
    if (SyncImagePixels(image) == MagickFalse)
      break;
    if ((image->progress_monitor != (MagickProgressMonitor) NULL) &&
        (QuantumTick(y,image->rows) != MagickFalse))
      {
        status=image->progress_monitor(EvaluateImageTag,y,image->rows,
          image->client_data);
        if (status == MagickFalse)
          break;
      }
  }
  return(y == (long) image->rows ? MagickTrue : MagickFalse);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
+     F x E v a l u a t e C h a n n e l E x p r e s s i o n                   %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  FxEvaluateChannelExpression() evaluates an expression and returns the
%  results.
%
%  The format of the FxEvaluateExpression method is:
%
%      MagickRealType FxEvaluateChannelExpression(FxInfo *fx_info,
%        const ChannelType channel,const long x,const long y,
%        MagickRealType *alpha,Exceptioninfo *exception)
%      MagickRealType FxEvaluateExpression(FxInfo *fx_info,
%        MagickRealType *alpha,Exceptioninfo *exception)
%
%  A description of each parameter follows:
%
%    o fx_info: The fx info.
%
%    o channel: The channel.
%
%    o x,y: the pixel position.
%
%    o alpha: the result.
%
%    o exception: Return any errors or warnings in this structure.
%
*/

static MagickRealType
  FxEvaluateSubexpression(FxInfo *,const ChannelType,const long,const long,
    const char *,MagickRealType *,ExceptionInfo *);

static inline MagickRealType FxMax(FxInfo *fx_info,const ChannelType channel,
  const long x,const long y,const char *expression,ExceptionInfo *exception)
{
  MagickRealType
    alpha,
    beta;

  alpha=FxEvaluateSubexpression(fx_info,channel,x,y,expression,&beta,exception);
  return((MagickRealType) MagickMax((double) alpha,(double) beta));
}

static inline MagickRealType FxMin(FxInfo *fx_info,ChannelType channel,
  const long x,const long y,const char *expression,ExceptionInfo *exception)
{
  MagickRealType
    alpha,
    beta;

  alpha=FxEvaluateSubexpression(fx_info,channel,x,y,expression,&beta,exception);
  return((MagickRealType) MagickMin((double) alpha,(double) beta));
}

static inline const char *FxSubexpression(const char *expression,
  ExceptionInfo *exception)
{
  const char
    *subexpression;

  register long
    level;

  level=0;
  subexpression=expression;
  while ((*subexpression != '\0') &&
         ((level != 1) || (strchr(")",(int) *subexpression) == (char *) NULL)))
  {
    if (strchr("(",(int) *subexpression) != (char *) NULL)
      level++;
    else
      if (strchr(")",(int) *subexpression) != (char *) NULL)
        level--;
    subexpression++;
  }
  if (*subexpression == '\0')
    (void) ThrowMagickException(exception,GetMagickModule(),OptionError,
      "UnbalancedParenthesis","`%s'",expression);
  return(subexpression);
}

static MagickRealType FxGetSymbol(FxInfo *fx_info,const ChannelType channel,
  const long x,const long y,const char *expression,ExceptionInfo *exception)
{
  char
    *q,
    subexpression[MaxTextExtent],
    symbol[MaxTextExtent];

  const char
    *p,
    *value;

  Image
    *image;

  MagickPixelPacket
    pixel;

  MagickRealType
    alpha,
    beta;

  PointInfo
    point;

  register long
    i;

  ResampleFilter
    *resample_filter;

  unsigned long
    level;

  p=expression;
  i=GetImageIndexInList(fx_info->images);
  level=0;
  point.x=(double) x;
  point.y=(double) y;
  if (isalpha((int) *(p+1)) == 0)
    {
      if (strchr("suv",(int) *p) != (char *) NULL)
        {
          switch (*p)
          {
            case 's':
            default:
            {
              i=GetImageIndexInList(fx_info->images);
              break;
            }
            case 'u': i=0; break;
            case 'v': i=1; break;
          }
          p++;