% July 1992 %
% %
% %
-% Copyright 1999-2014 ImageMagick Studio LLC, a non-profit organization %
+% Copyright 1999-2015 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 %
Include declarations.
*/
#include "MagickCore/studio.h"
-#include "MagickCore/property.h"
#include "MagickCore/animate.h"
+#include "MagickCore/artifact.h"
#include "MagickCore/blob.h"
#include "MagickCore/blob-private.h"
#include "MagickCore/cache.h"
#include "MagickCore/cache-private.h"
#include "MagickCore/cache-view.h"
+#include "MagickCore/channel.h"
#include "MagickCore/client.h"
#include "MagickCore/color.h"
#include "MagickCore/color-private.h"
#include "MagickCore/image-private.h"
#include "MagickCore/magic.h"
#include "MagickCore/magick.h"
+#include "MagickCore/matrix.h"
#include "MagickCore/memory_.h"
#include "MagickCore/module.h"
#include "MagickCore/monitor.h"
#include "MagickCore/monitor-private.h"
+#include "MagickCore/morphology-private.h"
#include "MagickCore/option.h"
#include "MagickCore/paint.h"
#include "MagickCore/pixel-accessor.h"
#include "MagickCore/profile.h"
+#include "MagickCore/property.h"
#include "MagickCore/quantize.h"
#include "MagickCore/quantum-private.h"
#include "MagickCore/random_.h"
% %
% %
% %
+% C a n n y E d g e I m a g e %
+% %
+% %
+% %
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%
+% CannyEdgeImage() uses a multi-stage algorithm to detect a wide range of
+% edges in images.
+%
+% The format of the CannyEdgeImage method is:
+%
+% Image *CannyEdgeImage(const Image *image,const double radius,
+% const double sigma,const double lower_percent,
+% const double upper_percent,ExceptionInfo *exception)
+%
+% A description of each parameter follows:
+%
+% o image: the image.
+%
+% o radius: the radius of the gaussian smoothing filter.
+%
+% o sigma: the sigma of the gaussian smoothing filter.
+%
+% o lower_precent: percentage of edge pixels in the lower threshold.
+%
+% o upper_percent: percentage of edge pixels in the upper threshold.
+%
+% o exception: return any errors or warnings in this structure.
+%
+*/
+
+typedef struct _CannyInfo
+{
+ double
+ magnitude,
+ intensity;
+
+ int
+ orientation;
+
+ ssize_t
+ x,
+ y;
+} CannyInfo;
+
+static inline MagickBooleanType IsAuthenticPixel(const Image *image,
+ const ssize_t x,const ssize_t y)
+{
+ if ((x < 0) || (x >= (ssize_t) image->columns))
+ return(MagickFalse);
+ if ((y < 0) || (y >= (ssize_t) image->rows))
+ return(MagickFalse);
+ return(MagickTrue);
+}
+
+static MagickBooleanType TraceEdges(Image *edge_image,CacheView *edge_view,
+ MatrixInfo *canny_cache,const ssize_t x,const ssize_t y,
+ const double lower_threshold,ExceptionInfo *exception)
+{
+ CannyInfo
+ edge,
+ pixel;
+
+ MagickBooleanType
+ status;
+
+ register Quantum
+ *q;
+
+ register ssize_t
+ i;
+
+ q=GetCacheViewAuthenticPixels(edge_view,x,y,1,1,exception);
+ if (q == (Quantum *) NULL)
+ return(MagickFalse);
+ *q=QuantumRange;
+ status=SyncCacheViewAuthenticPixels(edge_view,exception);
+ if (status == MagickFalse)
+ return(MagickFalse);;
+ if (GetMatrixElement(canny_cache,0,0,&edge) == MagickFalse)
+ return(MagickFalse);
+ edge.x=x;
+ edge.y=y;
+ if (SetMatrixElement(canny_cache,0,0,&edge) == MagickFalse)
+ return(MagickFalse);
+ for (i=1; i != 0; )
+ {
+ ssize_t
+ v;
+
+ i--;
+ status=GetMatrixElement(canny_cache,i,0,&edge);
+ if (status == MagickFalse)
+ return(MagickFalse);
+ for (v=(-1); v <= 1; v++)
+ {
+ ssize_t
+ u;
+
+ for (u=(-1); u <= 1; u++)
+ {
+ if ((u == 0) && (v == 0))
+ continue;
+ if (IsAuthenticPixel(edge_image,edge.x+u,edge.y+v) == MagickFalse)
+ continue;
+ /*
+ Not an edge if gradient value is below the lower threshold.
+ */
+ q=GetCacheViewAuthenticPixels(edge_view,edge.x+u,edge.y+v,1,1,
+ exception);
+ if (q == (Quantum *) NULL)
+ return(MagickFalse);
+ status=GetMatrixElement(canny_cache,edge.x+u,edge.y+v,&pixel);
+ if (status == MagickFalse)
+ return(MagickFalse);
+ if ((GetPixelIntensity(edge_image,q) == 0.0) &&
+ (pixel.intensity >= lower_threshold))
+ {
+ *q=QuantumRange;
+ status=SyncCacheViewAuthenticPixels(edge_view,exception);
+ if (status == MagickFalse)
+ return(MagickFalse);
+ edge.x+=u;
+ edge.y+=v;
+ status=SetMatrixElement(canny_cache,i,0,&edge);
+ if (status == MagickFalse)
+ return(MagickFalse);
+ i++;
+ }
+ }
+ }
+ }
+ return(MagickTrue);
+}
+
+MagickExport Image *CannyEdgeImage(const Image *image,const double radius,
+ const double sigma,const double lower_percent,const double upper_percent,
+ ExceptionInfo *exception)
+{
+#define CannyEdgeImageTag "CannyEdge/Image"
+
+ CacheView
+ *edge_view;
+
+ CannyInfo
+ pixel;
+
+ char
+ geometry[MagickPathExtent];
+
+ double
+ lower_threshold,
+ max,
+ min,
+ upper_threshold;
+
+ Image
+ *edge_image;
+
+ KernelInfo
+ *kernel_info;
+
+ MagickBooleanType
+ status;
+
+ MagickOffsetType
+ progress;
+
+ MatrixInfo
+ *canny_cache;
+
+ ssize_t
+ y;
+
+ assert(image != (const Image *) NULL);
+ assert(image->signature == MagickCoreSignature);
+ if (image->debug != MagickFalse)
+ (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
+ assert(exception != (ExceptionInfo *) NULL);
+ assert(exception->signature == MagickCoreSignature);
+ /*
+ Filter out noise.
+ */
+ (void) FormatLocaleString(geometry,MagickPathExtent,
+ "blur:%.20gx%.20g;blur:%.20gx%.20g+90",radius,sigma,radius,sigma);
+ kernel_info=AcquireKernelInfo(geometry,exception);
+ if (kernel_info == (KernelInfo *) NULL)
+ ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
+ edge_image=MorphologyApply(image,ConvolveMorphology,1,kernel_info,
+ UndefinedCompositeOp,0.0,exception);
+ kernel_info=DestroyKernelInfo(kernel_info);
+ if (edge_image == (Image *) NULL)
+ return((Image *) NULL);
+ if (SetImageColorspace(edge_image,GRAYColorspace,exception) == MagickFalse)
+ {
+ edge_image=DestroyImage(edge_image);
+ return((Image *) NULL);
+ }
+ (void) SetImageAlphaChannel(edge_image,OffAlphaChannel,exception);
+ /*
+ Find the intensity gradient of the image.
+ */
+ canny_cache=AcquireMatrixInfo(edge_image->columns,edge_image->rows,
+ sizeof(CannyInfo),exception);
+ if (canny_cache == (MatrixInfo *) NULL)
+ {
+ edge_image=DestroyImage(edge_image);
+ return((Image *) NULL);
+ }
+ status=MagickTrue;
+ edge_view=AcquireVirtualCacheView(edge_image,exception);
+#if defined(MAGICKCORE_OPENMP_SUPPORT)
+ #pragma omp parallel for schedule(static,4) shared(status) \
+ magick_threads(edge_image,edge_image,edge_image->rows,1)
+#endif
+ for (y=0; y < (ssize_t) edge_image->rows; y++)
+ {
+ register const Quantum
+ *restrict p;
+
+ register ssize_t
+ x;
+
+ if (status == MagickFalse)
+ continue;
+ p=GetCacheViewVirtualPixels(edge_view,0,y,edge_image->columns+1,2,
+ exception);
+ if (p == (const Quantum *) NULL)
+ {
+ status=MagickFalse;
+ continue;
+ }
+ for (x=0; x < (ssize_t) edge_image->columns; x++)
+ {
+ CannyInfo
+ pixel;
+
+ double
+ dx,
+ dy;
+
+ register const Quantum
+ *restrict kernel_pixels;
+
+ ssize_t
+ v;
+
+ static double
+ Gx[2][2] =
+ {
+ { -1.0, +1.0 },
+ { -1.0, +1.0 }
+ },
+ Gy[2][2] =
+ {
+ { +1.0, +1.0 },
+ { -1.0, -1.0 }
+ };
+
+ (void) ResetMagickMemory(&pixel,0,sizeof(pixel));
+ dx=0.0;
+ dy=0.0;
+ kernel_pixels=p;
+ for (v=0; v < 2; v++)
+ {
+ ssize_t
+ u;
+
+ for (u=0; u < 2; u++)
+ {
+ double
+ intensity;
+
+ intensity=GetPixelIntensity(edge_image,kernel_pixels+u);
+ dx+=0.5*Gx[v][u]*intensity;
+ dy+=0.5*Gy[v][u]*intensity;
+ }
+ kernel_pixels+=edge_image->columns+1;
+ }
+ pixel.magnitude=hypot(dx,dy);
+ pixel.orientation=0;
+ if (fabs(dx) > MagickEpsilon)
+ {
+ double
+ slope;
+
+ slope=dy/dx;
+ if (slope < 0.0)
+ {
+ if (slope < -2.41421356237)
+ pixel.orientation=0;
+ else
+ if (slope < -0.414213562373)
+ pixel.orientation=1;
+ else
+ pixel.orientation=2;
+ }
+ else
+ {
+ if (slope > 2.41421356237)
+ pixel.orientation=0;
+ else
+ if (slope > 0.414213562373)
+ pixel.orientation=3;
+ else
+ pixel.orientation=2;
+ }
+ }
+ if (SetMatrixElement(canny_cache,x,y,&pixel) == MagickFalse)
+ continue;
+ p+=GetPixelChannels(edge_image);
+ }
+ }
+ edge_view=DestroyCacheView(edge_view);
+ /*
+ Non-maxima suppression, remove pixels that are not considered to be part
+ of an edge.
+ */
+ progress=0;
+ (void) GetMatrixElement(canny_cache,0,0,&pixel);
+ max=pixel.intensity;
+ min=pixel.intensity;
+ edge_view=AcquireAuthenticCacheView(edge_image,exception);
+#if defined(MAGICKCORE_OPENMP_SUPPORT)
+ #pragma omp parallel for schedule(static,4) shared(status) \
+ magick_threads(edge_image,edge_image,edge_image->rows,1)
+#endif
+ for (y=0; y < (ssize_t) edge_image->rows; y++)
+ {
+ register Quantum
+ *restrict q;
+
+ register ssize_t
+ x;
+
+ if (status == MagickFalse)
+ continue;
+ q=GetCacheViewAuthenticPixels(edge_view,0,y,edge_image->columns,1,
+ exception);
+ if (q == (Quantum *) NULL)
+ {
+ status=MagickFalse;
+ continue;
+ }
+ for (x=0; x < (ssize_t) edge_image->columns; x++)
+ {
+ CannyInfo
+ alpha_pixel,
+ beta_pixel,
+ pixel;
+
+ (void) GetMatrixElement(canny_cache,x,y,&pixel);
+ switch (pixel.orientation)
+ {
+ case 0:
+ default:
+ {
+ /*
+ 0 degrees, north and south.
+ */
+ (void) GetMatrixElement(canny_cache,x,y-1,&alpha_pixel);
+ (void) GetMatrixElement(canny_cache,x,y+1,&beta_pixel);
+ break;
+ }
+ case 1:
+ {
+ /*
+ 45 degrees, northwest and southeast.
+ */
+ (void) GetMatrixElement(canny_cache,x-1,y-1,&alpha_pixel);
+ (void) GetMatrixElement(canny_cache,x+1,y+1,&beta_pixel);
+ break;
+ }
+ case 2:
+ {
+ /*
+ 90 degrees, east and west.
+ */
+ (void) GetMatrixElement(canny_cache,x-1,y,&alpha_pixel);
+ (void) GetMatrixElement(canny_cache,x+1,y,&beta_pixel);
+ break;
+ }
+ case 3:
+ {
+ /*
+ 135 degrees, northeast and southwest.
+ */
+ (void) GetMatrixElement(canny_cache,x+1,y-1,&beta_pixel);
+ (void) GetMatrixElement(canny_cache,x-1,y+1,&alpha_pixel);
+ break;
+ }
+ }
+ pixel.intensity=pixel.magnitude;
+ if ((pixel.magnitude < alpha_pixel.magnitude) ||
+ (pixel.magnitude < beta_pixel.magnitude))
+ pixel.intensity=0;
+ (void) SetMatrixElement(canny_cache,x,y,&pixel);
+#if defined(MAGICKCORE_OPENMP_SUPPORT)
+ #pragma omp critical (MagickCore_CannyEdgeImage)
+#endif
+ {
+ if (pixel.intensity < min)
+ min=pixel.intensity;
+ if (pixel.intensity > max)
+ max=pixel.intensity;
+ }
+ *q=0;
+ q+=GetPixelChannels(edge_image);
+ }
+ if (SyncCacheViewAuthenticPixels(edge_view,exception) == MagickFalse)
+ status=MagickFalse;
+ }
+ edge_view=DestroyCacheView(edge_view);
+ /*
+ Estimate hysteresis threshold.
+ */
+ lower_threshold=lower_percent*(max-min)+min;
+ upper_threshold=upper_percent*(max-min)+min;
+ /*
+ Hysteresis threshold.
+ */
+ edge_view=AcquireAuthenticCacheView(edge_image,exception);
+ for (y=0; y < (ssize_t) edge_image->rows; y++)
+ {
+ register ssize_t
+ x;
+
+ if (status == MagickFalse)
+ continue;
+ for (x=0; x < (ssize_t) edge_image->columns; x++)
+ {
+ CannyInfo
+ pixel;
+
+ register const Quantum
+ *restrict p;
+
+ /*
+ Edge if pixel gradient higher than upper threshold.
+ */
+ p=GetCacheViewVirtualPixels(edge_view,x,y,1,1,exception);
+ if (p == (const Quantum *) NULL)
+ continue;
+ status=GetMatrixElement(canny_cache,x,y,&pixel);
+ if (status == MagickFalse)
+ continue;
+ if ((GetPixelIntensity(edge_image,p) == 0.0) &&
+ (pixel.intensity >= upper_threshold))
+ status=TraceEdges(edge_image,edge_view,canny_cache,x,y,lower_threshold,
+ exception);
+ }
+ if (image->progress_monitor != (MagickProgressMonitor) NULL)
+ {
+ MagickBooleanType
+ proceed;
+
+#if defined(MAGICKCORE_OPENMP_SUPPORT)
+ #pragma omp critical (MagickCore_CannyEdgeImage)
+#endif
+ proceed=SetImageProgress(image,CannyEdgeImageTag,progress++,
+ image->rows);
+ if (proceed == MagickFalse)
+ status=MagickFalse;
+ }
+ }
+ edge_view=DestroyCacheView(edge_view);
+ /*
+ Free resources.
+ */
+ canny_cache=DestroyMatrixInfo(canny_cache);
+ return(edge_image);
+}
+\f
+/*
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %
+% %
+% %
% G e t I m a g e F e a t u r e s %
% %
% %
%
*/
-static inline ssize_t MagickAbsoluteValue(const ssize_t x)
-{
- if (x < 0)
- return(-x);
- return(x);
-}
-
static inline double MagickLog10(const double x)
{
-#define Log10Epsilon (1.0e-15)
+#define Log10Epsilon (1.0e-11)
if (fabs(x) < Log10Epsilon)
- return(log10(fabs(Log10Epsilon)));
+ return(log10(Log10Epsilon));
return(log10(fabs(x)));
}
number_grays;
assert(image != (Image *) NULL);
- assert(image->signature == MagickSignature);
+ assert(image->signature == MagickCoreSignature);
if (image->debug != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
if ((image->columns < (distance+1)) || (image->rows < (distance+1)))
if (image->colorspace == CMYKColorspace)
grays[ScaleQuantumToMap(GetPixelBlack(image,p))].black=
ScaleQuantumToMap(GetPixelBlack(image,p));
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
grays[ScaleQuantumToMap(GetPixelAlpha(image,p))].alpha=
ScaleQuantumToMap(GetPixelAlpha(image,p));
p+=GetPixelChannels(image);
if (image->colorspace == CMYKColorspace)
if (grays[i].black != ~0U)
grays[gray.black++].black=grays[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
if (grays[i].alpha != ~0U)
grays[gray.alpha++].alpha=grays[i].alpha;
}
if (image->colorspace == CMYKColorspace)
if (gray.black > number_grays)
number_grays=gray.black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
if (gray.alpha > number_grays)
number_grays=gray.alpha;
cooccurrence=(ChannelStatistics **) AcquireQuantumMemory(number_grays,
cooccurrence[u][v].direction[i].black++;
cooccurrence[v][u].direction[i].black++;
}
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
{
u=0;
v=0;
cooccurrence[x][y].direction[i].blue*=normalize;
if (image->colorspace == CMYKColorspace)
cooccurrence[x][y].direction[i].black*=normalize;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
cooccurrence[x][y].direction[i].alpha*=normalize;
}
}
channel_features[BlackPixelChannel].angular_second_moment[i]+=
cooccurrence[x][y].direction[i].black*
cooccurrence[x][y].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].angular_second_moment[i]+=
cooccurrence[x][y].direction[i].alpha*
cooccurrence[x][y].direction[i].alpha;
sum[y].direction[i].blue+=cooccurrence[x][y].direction[i].blue;
if (image->colorspace == CMYKColorspace)
sum[y].direction[i].black+=cooccurrence[x][y].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
sum[y].direction[i].alpha+=cooccurrence[x][y].direction[i].alpha;
correlation.direction[i].red+=x*y*cooccurrence[x][y].direction[i].red;
correlation.direction[i].green+=x*y*
if (image->colorspace == CMYKColorspace)
correlation.direction[i].black+=x*y*
cooccurrence[x][y].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
correlation.direction[i].alpha+=x*y*
cooccurrence[x][y].direction[i].alpha;
/*
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].inverse_difference_moment[i]+=
cooccurrence[x][y].direction[i].black/((y-x)*(y-x)+1);
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].inverse_difference_moment[i]+=
cooccurrence[x][y].direction[i].alpha/((y-x)*(y-x)+1);
/*
if (image->colorspace == CMYKColorspace)
density_xy[y+x+2].direction[i].black+=
cooccurrence[x][y].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
density_xy[y+x+2].direction[i].alpha+=
cooccurrence[x][y].direction[i].alpha;
/*
channel_features[BlackPixelChannel].entropy[i]-=
cooccurrence[x][y].direction[i].black*
MagickLog10(cooccurrence[x][y].direction[i].black);
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].entropy[i]-=
cooccurrence[x][y].direction[i].alpha*
MagickLog10(cooccurrence[x][y].direction[i].alpha);
density_x[x].direction[i].red+=cooccurrence[x][y].direction[i].red;
density_x[x].direction[i].green+=cooccurrence[x][y].direction[i].green;
density_x[x].direction[i].blue+=cooccurrence[x][y].direction[i].blue;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
density_x[x].direction[i].alpha+=
cooccurrence[x][y].direction[i].alpha;
if (image->colorspace == CMYKColorspace)
if (image->colorspace == CMYKColorspace)
density_y[y].direction[i].black+=
cooccurrence[x][y].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
density_y[y].direction[i].alpha+=
cooccurrence[x][y].direction[i].alpha;
}
mean.direction[i].black+=y*sum[y].direction[i].black;
sum_squares.direction[i].black+=y*y*sum[y].direction[i].black;
}
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
{
mean.direction[i].alpha+=y*sum[y].direction[i].alpha;
sum_squares.direction[i].alpha+=y*y*sum[y].direction[i].alpha;
(mean.direction[i].black*mean.direction[i].black))*sqrt(
sum_squares.direction[i].black-(mean.direction[i].black*
mean.direction[i].black)));
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].correlation[i]=
(correlation.direction[i].alpha-mean.direction[i].alpha*
mean.direction[i].alpha)/(sqrt(sum_squares.direction[i].alpha-
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].sum_average[i]+=
x*density_xy[x].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].sum_average[i]+=
x*density_xy[x].direction[i].alpha;
/*
channel_features[BlackPixelChannel].sum_entropy[i]-=
density_xy[x].direction[i].black*
MagickLog10(density_xy[x].direction[i].black);
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].sum_entropy[i]-=
density_xy[x].direction[i].alpha*
MagickLog10(density_xy[x].direction[i].alpha);
(x-channel_features[BlackPixelChannel].sum_entropy[i])*
(x-channel_features[BlackPixelChannel].sum_entropy[i])*
density_xy[x].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].sum_variance[i]+=
(x-channel_features[AlphaPixelChannel].sum_entropy[i])*
(x-channel_features[AlphaPixelChannel].sum_entropy[i])*
if (image->colorspace == CMYKColorspace)
variance.direction[i].black+=(y-mean.direction[i].black+1)*
(y-mean.direction[i].black+1)*cooccurrence[x][y].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
variance.direction[i].alpha+=(y-mean.direction[i].alpha+1)*
(y-mean.direction[i].alpha+1)*
cooccurrence[x][y].direction[i].alpha;
if (image->colorspace == CMYKColorspace)
density_xy[MagickAbsoluteValue(y-x)].direction[i].black+=
cooccurrence[x][y].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
density_xy[MagickAbsoluteValue(y-x)].direction[i].alpha+=
cooccurrence[x][y].direction[i].alpha;
/*
if (image->colorspace == CMYKColorspace)
entropy_xy.direction[i].black-=cooccurrence[x][y].direction[i].black*
MagickLog10(cooccurrence[x][y].direction[i].black);
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
entropy_xy.direction[i].alpha-=
cooccurrence[x][y].direction[i].alpha*MagickLog10(
cooccurrence[x][y].direction[i].alpha);
entropy_xy1.direction[i].black-=(
cooccurrence[x][y].direction[i].black*MagickLog10(
density_x[x].direction[i].black*density_y[y].direction[i].black));
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
entropy_xy1.direction[i].alpha-=(
cooccurrence[x][y].direction[i].alpha*MagickLog10(
density_x[x].direction[i].alpha*density_y[y].direction[i].alpha));
entropy_xy2.direction[i].black-=(density_x[x].direction[i].black*
density_y[y].direction[i].black*MagickLog10(
density_x[x].direction[i].black*density_y[y].direction[i].black));
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
entropy_xy2.direction[i].alpha-=(density_x[x].direction[i].alpha*
density_y[y].direction[i].alpha*MagickLog10(
density_x[x].direction[i].alpha*density_y[y].direction[i].alpha));
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].variance_sum_of_squares[i]=
variance.direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].variance_sum_of_squares[i]=
variance.direction[i].alpha;
}
variance.direction[i].blue+=density_xy[x].direction[i].blue;
if (image->colorspace == CMYKColorspace)
variance.direction[i].black+=density_xy[x].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
variance.direction[i].alpha+=density_xy[x].direction[i].alpha;
sum_squares.direction[i].red+=density_xy[x].direction[i].red*
density_xy[x].direction[i].red;
if (image->colorspace == CMYKColorspace)
sum_squares.direction[i].black+=density_xy[x].direction[i].black*
density_xy[x].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
sum_squares.direction[i].alpha+=density_xy[x].direction[i].alpha*
density_xy[x].direction[i].alpha;
/*
channel_features[BlackPixelChannel].difference_entropy[i]-=
density_xy[x].direction[i].black*
MagickLog10(density_xy[x].direction[i].black);
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].difference_entropy[i]-=
density_xy[x].direction[i].alpha*
MagickLog10(density_xy[x].direction[i].alpha);
if (image->colorspace == CMYKColorspace)
entropy_x.direction[i].black-=(density_x[x].direction[i].black*
MagickLog10(density_x[x].direction[i].black));
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
entropy_x.direction[i].alpha-=(density_x[x].direction[i].alpha*
MagickLog10(density_x[x].direction[i].alpha));
entropy_y.direction[i].red-=(density_y[x].direction[i].red*
if (image->colorspace == CMYKColorspace)
entropy_y.direction[i].black-=(density_y[x].direction[i].black*
MagickLog10(density_y[x].direction[i].black));
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
entropy_y.direction[i].alpha-=(density_y[x].direction[i].alpha*
MagickLog10(density_y[x].direction[i].alpha));
}
(((double) number_grays*number_grays*sum_squares.direction[i].black)-
(variance.direction[i].black*variance.direction[i].black))/
((double) number_grays*number_grays*number_grays*number_grays);
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].difference_variance[i]=
(((double) number_grays*number_grays*sum_squares.direction[i].alpha)-
(variance.direction[i].alpha*variance.direction[i].alpha))/
(entropy_xy.direction[i].black-entropy_xy1.direction[i].black)/
(entropy_x.direction[i].black > entropy_y.direction[i].black ?
entropy_x.direction[i].black : entropy_y.direction[i].black);
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].measure_of_correlation_1[i]=
(entropy_xy.direction[i].alpha-entropy_xy1.direction[i].alpha)/
(entropy_x.direction[i].alpha > entropy_y.direction[i].alpha ?
entropy_x.direction[i].alpha : entropy_y.direction[i].alpha);
channel_features[RedPixelChannel].measure_of_correlation_2[i]=
- (sqrt(fabs(1.0-exp(-2.0*(entropy_xy2.direction[i].red-
+ (sqrt(fabs(1.0-exp(-2.0*(double) (entropy_xy2.direction[i].red-
entropy_xy.direction[i].red)))));
channel_features[GreenPixelChannel].measure_of_correlation_2[i]=
- (sqrt(fabs(1.0-exp(-2.0*(entropy_xy2.direction[i].green-
+ (sqrt(fabs(1.0-exp(-2.0*(double) (entropy_xy2.direction[i].green-
entropy_xy.direction[i].green)))));
channel_features[BluePixelChannel].measure_of_correlation_2[i]=
- (sqrt(fabs(1.0-exp(-2.0*(entropy_xy2.direction[i].blue-
+ (sqrt(fabs(1.0-exp(-2.0*(double) (entropy_xy2.direction[i].blue-
entropy_xy.direction[i].blue)))));
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].measure_of_correlation_2[i]=
- (sqrt(fabs(1.0-exp(-2.0*(entropy_xy2.direction[i].black-
+ (sqrt(fabs(1.0-exp(-2.0*(double) (entropy_xy2.direction[i].black-
entropy_xy.direction[i].black)))));
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].measure_of_correlation_2[i]=
- (sqrt(fabs(1.0-exp(-2.0*(entropy_xy2.direction[i].alpha-
+ (sqrt(fabs(1.0-exp(-2.0*(double) (entropy_xy2.direction[i].alpha-
entropy_xy.direction[i].alpha)))));
}
/*
pixel.direction[i].blue+=cooccurrence[x][y].direction[i].blue;
if (image->colorspace == CMYKColorspace)
pixel.direction[i].black+=cooccurrence[x][y].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
pixel.direction[i].alpha+=
cooccurrence[x][y].direction[i].alpha;
}
Q[z][y].direction[i].black+=cooccurrence[z][x].direction[i].black*
cooccurrence[y][x].direction[i].black/
density_x[z].direction[i].black/density_y[x].direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
Q[z][y].direction[i].alpha+=
cooccurrence[z][x].direction[i].alpha*
cooccurrence[y][x].direction[i].alpha/
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].contrast[i]+=z*z*
pixel.direction[i].black;
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].contrast[i]+=z*z*
pixel.direction[i].alpha;
}
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].maximum_correlation_coefficient[i]=
sqrt((double) -1.0);
- if (image->alpha_trait == BlendPixelTrait)
+ if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].maximum_correlation_coefficient[i]=
sqrt((double) -1.0);
}
cooccurrence=(ChannelStatistics **) RelinquishMagickMemory(cooccurrence);
return(channel_features);
}
+\f
+/*
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %
+% %
+% %
+% H o u g h L i n e I m a g e %
+% %
+% %
+% %
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%
+% Use HoughLineImage() in conjunction with any binary edge extracted image (we
+% recommand Canny) to identify lines in the image. The algorithm accumulates
+% counts for every white pixel for every possible orientation (for angles from
+% 0 to 179 in 1 degree increments) and distance from the center of the image to
+% the corner (in 1 px increments) and stores the counts in an accumulator matrix
+% of angle vs distance. The size of the accumulator is 180x(diagonal/2). Next
+% it searches this space for peaks in counts and converts the locations of the
+% peaks to slope and intercept in the normal x,y input image space. Use the
+% slope/intercepts to find the endpoints clipped to the bounds of the image. The
+% lines are then drawn. The counts are a measure of the length of the lines
+%
+% The format of the HoughLineImage method is:
+%
+% Image *HoughLineImage(const Image *image,const size_t width,
+% const size_t height,const size_t threshold,ExceptionInfo *exception)
+%
+% A description of each parameter follows:
+%
+% o image: the image.
+%
+% o width, height: find line pairs as local maxima in this neighborhood.
+%
+% o threshold: the line count threshold.
+%
+% o exception: return any errors or warnings in this structure.
+%
+*/
+
+static inline double MagickRound(double x)
+{
+ /*
+ Round the fraction to nearest integer.
+ */
+ if ((x-floor(x)) < (ceil(x)-x))
+ return(floor(x));
+ return(ceil(x));
+}
+
+MagickExport Image *HoughLineImage(const Image *image,const size_t width,
+ const size_t height,const size_t threshold,ExceptionInfo *exception)
+{
+#define HoughLineImageTag "HoughLine/Image"
+
+ CacheView
+ *image_view;
+
+ char
+ message[MagickPathExtent],
+ path[MagickPathExtent];
+
+ const char
+ *artifact;
+
+ double
+ hough_height;
+
+ Image
+ *lines_image = NULL;
+
+ ImageInfo
+ *image_info;
+
+ int
+ file;
+
+ MagickBooleanType
+ status;
+
+ MagickOffsetType
+ progress;
+
+ MatrixInfo
+ *accumulator;
+
+ PointInfo
+ center;
+
+ register ssize_t
+ y;
+
+ size_t
+ accumulator_height,
+ accumulator_width,
+ line_count;
+
+ /*
+ Create the accumulator.
+ */
+ assert(image != (const Image *) NULL);
+ assert(image->signature == MagickCoreSignature);
+ if (image->debug != MagickFalse)
+ (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
+ assert(exception != (ExceptionInfo *) NULL);
+ assert(exception->signature == MagickCoreSignature);
+ accumulator_width=180;
+ hough_height=((sqrt(2.0)*(double) (image->rows > image->columns ?
+ image->rows : image->columns))/2.0);
+ accumulator_height=(size_t) (2.0*hough_height);
+ accumulator=AcquireMatrixInfo(accumulator_width,accumulator_height,
+ sizeof(double),exception);
+ if (accumulator == (MatrixInfo *) NULL)
+ ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
+ if (NullMatrix(accumulator) == MagickFalse)
+ {
+ accumulator=DestroyMatrixInfo(accumulator);
+ ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
+ }
+ /*
+ Populate the accumulator.
+ */
+ status=MagickTrue;
+ progress=0;
+ center.x=(double) image->columns/2.0;
+ center.y=(double) image->rows/2.0;
+ image_view=AcquireVirtualCacheView(image,exception);
+ for (y=0; y < (ssize_t) image->rows; y++)
+ {
+ register const Quantum
+ *restrict p;
+
+ register ssize_t
+ x;
+
+ if (status == MagickFalse)
+ continue;
+ p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
+ if (p == (Quantum *) NULL)
+ {
+ status=MagickFalse;
+ continue;
+ }
+ for (x=0; x < (ssize_t) image->columns; x++)
+ {
+ if (GetPixelIntensity(image,p) > (QuantumRange/2.0))
+ {
+ register ssize_t
+ i;
+
+ for (i=0; i < 180; i++)
+ {
+ double
+ count,
+ radius;
+
+ radius=(((double) x-center.x)*cos(DegreesToRadians((double) i)))+
+ (((double) y-center.y)*sin(DegreesToRadians((double) i)));
+ (void) GetMatrixElement(accumulator,i,(ssize_t)
+ MagickRound(radius+hough_height),&count);
+ count++;
+ (void) SetMatrixElement(accumulator,i,(ssize_t)
+ MagickRound(radius+hough_height),&count);
+ }
+ }
+ p+=GetPixelChannels(image);
+ }
+ if (image->progress_monitor != (MagickProgressMonitor) NULL)
+ {
+ MagickBooleanType
+ proceed;
+
+#if defined(MAGICKCORE_OPENMP_SUPPORT)
+ #pragma omp critical (MagickCore_CannyEdgeImage)
+#endif
+ proceed=SetImageProgress(image,CannyEdgeImageTag,progress++,
+ image->rows);
+ if (proceed == MagickFalse)
+ status=MagickFalse;
+ }
+ }
+ image_view=DestroyCacheView(image_view);
+ if (status == MagickFalse)
+ {
+ accumulator=DestroyMatrixInfo(accumulator);
+ return((Image *) NULL);
+ }
+ /*
+ Generate line segments from accumulator.
+ */
+ file=AcquireUniqueFileResource(path);
+ if (file == -1)
+ {
+ accumulator=DestroyMatrixInfo(accumulator);
+ return((Image *) NULL);
+ }
+ (void) FormatLocaleString(message,MagickPathExtent,
+ "# Hough line transform: %.20gx%.20g%+.20g\n",(double) width,
+ (double) height,(double) threshold);
+ if (write(file,message,strlen(message)) != (ssize_t) strlen(message))
+ status=MagickFalse;
+ (void) FormatLocaleString(message,MagickPathExtent,"viewbox 0 0 %.20g %.20g\n",
+ (double) image->columns,(double) image->rows);
+ if (write(file,message,strlen(message)) != (ssize_t) strlen(message))
+ status=MagickFalse;
+ line_count=image->columns > image->rows ? image->columns/4 : image->rows/4;
+ if (threshold != 0)
+ line_count=threshold;
+ for (y=0; y < (ssize_t) accumulator_height; y++)
+ {
+ register ssize_t
+ x;
+
+ for (x=0; x < (ssize_t) accumulator_width; x++)
+ {
+ double
+ count;
+
+ (void) GetMatrixElement(accumulator,x,y,&count);
+ if (count >= (double) line_count)
+ {
+ double
+ maxima;
+
+ SegmentInfo
+ line;
+
+ ssize_t
+ v;
+
+ /*
+ Is point a local maxima?
+ */
+ maxima=count;
+ for (v=(-((ssize_t) height/2)); v <= (((ssize_t) height/2)); v++)
+ {
+ ssize_t
+ u;
+
+ for (u=(-((ssize_t) width/2)); u <= (((ssize_t) width/2)); u++)
+ {
+ if ((u != 0) || (v !=0))
+ {
+ (void) GetMatrixElement(accumulator,x+u,y+v,&count);
+ if (count > maxima)
+ {
+ maxima=count;
+ break;
+ }
+ }
+ }
+ if (u < (ssize_t) (width/2))
+ break;
+ }
+ (void) GetMatrixElement(accumulator,x,y,&count);
+ if (maxima > count)
+ continue;
+ if ((x >= 45) && (x <= 135))
+ {
+ /*
+ y = (r-x cos(t))/sin(t)
+ */
+ line.x1=0.0;
+ line.y1=((double) (y-(accumulator_height/2.0))-((line.x1-
+ (image->columns/2.0))*cos(DegreesToRadians((double) x))))/
+ sin(DegreesToRadians((double) x))+(image->rows/2.0);
+ line.x2=(double) image->columns;
+ line.y2=((double) (y-(accumulator_height/2.0))-((line.x2-
+ (image->columns/2.0))*cos(DegreesToRadians((double) x))))/
+ sin(DegreesToRadians((double) x))+(image->rows/2.0);
+ }
+ else
+ {
+ /*
+ x = (r-y cos(t))/sin(t)
+ */
+ line.y1=0.0;
+ line.x1=((double) (y-(accumulator_height/2.0))-((line.y1-
+ (image->rows/2.0))*sin(DegreesToRadians((double) x))))/
+ cos(DegreesToRadians((double) x))+(image->columns/2.0);
+ line.y2=(double) image->rows;
+ line.x2=((double) (y-(accumulator_height/2.0))-((line.y2-
+ (image->rows/2.0))*sin(DegreesToRadians((double) x))))/
+ cos(DegreesToRadians((double) x))+(image->columns/2.0);
+ }
+ (void) FormatLocaleString(message,MagickPathExtent,
+ "line %g,%g %g,%g # %g\n",line.x1,line.y1,line.x2,line.y2,maxima);
+ if (write(file,message,strlen(message)) != (ssize_t) strlen(message))
+ status=MagickFalse;
+ }
+ }
+ }
+ (void) close(file);
+ /*
+ Render lines to image canvas.
+ */
+ image_info=AcquireImageInfo();
+ image_info->background_color=image->background_color;
+ (void) FormatLocaleString(image_info->filename,MagickPathExtent,"mvg:%s",path);
+ artifact=GetImageArtifact(image,"background");
+ if (artifact != (const char *) NULL)
+ (void) SetImageOption(image_info,"background",artifact);
+ artifact=GetImageArtifact(image,"fill");
+ if (artifact != (const char *) NULL)
+ (void) SetImageOption(image_info,"fill",artifact);
+ artifact=GetImageArtifact(image,"stroke");
+ if (artifact != (const char *) NULL)
+ (void) SetImageOption(image_info,"stroke",artifact);
+ artifact=GetImageArtifact(image,"strokewidth");
+ if (artifact != (const char *) NULL)
+ (void) SetImageOption(image_info,"strokewidth",artifact);
+ lines_image=ReadImage(image_info,exception);
+ artifact=GetImageArtifact(image,"hough-lines:accumulator");
+ if ((lines_image != (Image *) NULL) &&
+ (IsStringTrue(artifact) != MagickFalse))
+ {
+ Image
+ *accumulator_image;
+
+ accumulator_image=MatrixToImage(accumulator,exception);
+ if (accumulator_image != (Image *) NULL)
+ AppendImageToList(&lines_image,accumulator_image);
+ }
+ /*
+ Free resources.
+ */
+ accumulator=DestroyMatrixInfo(accumulator);
+ image_info=DestroyImageInfo(image_info);
+ (void) RelinquishUniqueFileResource(path);
+ return(GetFirstImageInList(lines_image));
+}
+\f
+/*
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %
+% %
+% %
+% M e a n S h i f t I m a g e %
+% %
+% %
+% %
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%
+% MeanShiftImage() delineate arbitrarily shaped clusters in the image. For
+% each pixel, it visits all the pixels in the neighborhood specified by
+% the window centered at the pixel and excludes those that are outside the
+% radius=(window-1)/2 surrounding the pixel. From those pixels, it finds those
+% that are within the specified color distance from the current mean, and
+% computes a new x,y centroid from those coordinates and a new mean. This new
+% x,y centroid is used as the center for a new window. This process iterates
+% until it converges and the final mean is replaces the (original window
+% center) pixel value. It repeats this process for the next pixel, etc.,
+% until it processes all pixels in the image. Results are typically better with
+% colorspaces other than sRGB. We recommend YIQ, YUV or YCbCr.
+%
+% The format of the MeanShiftImage method is:
+%
+% Image *MeanShiftImage(const Image *image,const size_t width,
+% const size_t height,const double color_distance,
+% ExceptionInfo *exception)
+%
+% A description of each parameter follows:
+%
+% o image: the image.
+%
+% o width, height: find pixels in this neighborhood.
+%
+% o color_distance: the color distance.
+%
+% o exception: return any errors or warnings in this structure.
+%
+*/
+MagickExport Image *MeanShiftImage(const Image *image,const size_t width,
+ const size_t height,const double color_distance,ExceptionInfo *exception)
+{
+#define MaxMeanShiftIterations 100
+#define MeanShiftImageTag "MeanShift/Image"
+
+ CacheView
+ *image_view,
+ *mean_view,
+ *pixel_view;
+
+ Image
+ *mean_image;
+
+ MagickBooleanType
+ status;
+
+ MagickOffsetType
+ progress;
+
+ ssize_t
+ y;
+
+ assert(image != (const Image *) NULL);
+ assert(image->signature == MagickCoreSignature);
+ if (image->debug != MagickFalse)
+ (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
+ assert(exception != (ExceptionInfo *) NULL);
+ assert(exception->signature == MagickCoreSignature);
+ mean_image=CloneImage(image,image->columns,image->rows,MagickTrue,exception);
+ if (mean_image == (Image *) NULL)
+ return((Image *) NULL);
+ if (SetImageStorageClass(mean_image,DirectClass,exception) == MagickFalse)
+ {
+ mean_image=DestroyImage(mean_image);
+ return((Image *) NULL);
+ }
+ status=MagickTrue;
+ progress=0;
+ image_view=AcquireVirtualCacheView(image,exception);
+ pixel_view=AcquireVirtualCacheView(image,exception);
+ mean_view=AcquireAuthenticCacheView(mean_image,exception);
+#if defined(MAGICKCORE_OPENMP_SUPPORT)
+ #pragma omp parallel for schedule(static,4) shared(status,progress) \
+ magick_threads(mean_image,mean_image,mean_image->rows,1)
+#endif
+ for (y=0; y < (ssize_t) mean_image->rows; y++)
+ {
+ register const Quantum
+ *restrict p;
+
+ register Quantum
+ *restrict q;
+
+ register ssize_t
+ x;
+
+ if (status == MagickFalse)
+ continue;
+ p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
+ q=GetCacheViewAuthenticPixels(mean_view,0,y,mean_image->columns,1,
+ exception);
+ if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
+ {
+ status=MagickFalse;
+ continue;
+ }
+ for (x=0; x < (ssize_t) mean_image->columns; x++)
+ {
+ PixelInfo
+ mean_pixel,
+ previous_pixel;
+
+ PointInfo
+ mean_location,
+ previous_location;
+
+ register ssize_t
+ i;
+
+ GetPixelInfo(image,&mean_pixel);
+ GetPixelInfoPixel(image,p,&mean_pixel);
+ mean_location.x=(double) x;
+ mean_location.y=(double) y;
+ for (i=0; i < MaxMeanShiftIterations; i++)
+ {
+ double
+ distance,
+ gamma;
+
+ PixelInfo
+ sum_pixel;
+
+ PointInfo
+ sum_location;
+
+ ssize_t
+ count,
+ v;
+
+ sum_location.x=0.0;
+ sum_location.y=0.0;
+ GetPixelInfo(image,&sum_pixel);
+ previous_location=mean_location;
+ previous_pixel=mean_pixel;
+ count=0;
+ for (v=(-((ssize_t) height/2)); v <= (((ssize_t) height/2)); v++)
+ {
+ ssize_t
+ u;
+
+ for (u=(-((ssize_t) width/2)); u <= (((ssize_t) width/2)); u++)
+ {
+ if ((v*v+u*u) <= (ssize_t) ((width/2)*(height/2)))
+ {
+ PixelInfo
+ pixel;
+
+ status=GetOneCacheViewVirtualPixelInfo(pixel_view,(ssize_t)
+ MagickRound(mean_location.x+u),(ssize_t) MagickRound(
+ mean_location.y+v),&pixel,exception);
+ distance=(mean_pixel.red-pixel.red)*(mean_pixel.red-pixel.red)+
+ (mean_pixel.green-pixel.green)*(mean_pixel.green-pixel.green)+
+ (mean_pixel.blue-pixel.blue)*(mean_pixel.blue-pixel.blue);
+ if (distance <= (color_distance*color_distance))
+ {
+ sum_location.x+=mean_location.x+u;
+ sum_location.y+=mean_location.y+v;
+ sum_pixel.red+=pixel.red;
+ sum_pixel.green+=pixel.green;
+ sum_pixel.blue+=pixel.blue;
+ sum_pixel.alpha+=pixel.alpha;
+ count++;
+ }
+ }
+ }
+ }
+ gamma=1.0/count;
+ mean_location.x=gamma*sum_location.x;
+ mean_location.y=gamma*sum_location.y;
+ mean_pixel.red=gamma*sum_pixel.red;
+ mean_pixel.green=gamma*sum_pixel.green;
+ mean_pixel.blue=gamma*sum_pixel.blue;
+ mean_pixel.alpha=gamma*sum_pixel.alpha;
+ distance=(mean_location.x-previous_location.x)*
+ (mean_location.x-previous_location.x)+
+ (mean_location.y-previous_location.y)*
+ (mean_location.y-previous_location.y)+
+ 255.0*QuantumScale*(mean_pixel.red-previous_pixel.red)*
+ 255.0*QuantumScale*(mean_pixel.red-previous_pixel.red)+
+ 255.0*QuantumScale*(mean_pixel.green-previous_pixel.green)*
+ 255.0*QuantumScale*(mean_pixel.green-previous_pixel.green)+
+ 255.0*QuantumScale*(mean_pixel.blue-previous_pixel.blue)*
+ 255.0*QuantumScale*(mean_pixel.blue-previous_pixel.blue);
+ if (distance <= 3.0)
+ break;
+ }
+ SetPixelRed(mean_image,ClampToQuantum(mean_pixel.red),q);
+ SetPixelGreen(mean_image,ClampToQuantum(mean_pixel.green),q);
+ SetPixelBlue(mean_image,ClampToQuantum(mean_pixel.blue),q);
+ SetPixelAlpha(mean_image,ClampToQuantum(mean_pixel.alpha),q);
+ p+=GetPixelChannels(image);
+ q+=GetPixelChannels(mean_image);
+ }
+ if (SyncCacheViewAuthenticPixels(mean_view,exception) == MagickFalse)
+ status=MagickFalse;
+ if (image->progress_monitor != (MagickProgressMonitor) NULL)
+ {
+ MagickBooleanType
+ proceed;
+
+#if defined(MAGICKCORE_OPENMP_SUPPORT)
+ #pragma omp critical (MagickCore_MeanShiftImage)
+#endif
+ proceed=SetImageProgress(image,MeanShiftImageTag,progress++,
+ image->rows);
+ if (proceed == MagickFalse)
+ status=MagickFalse;
+ }
+ }
+ mean_view=DestroyCacheView(mean_view);
+ pixel_view=DestroyCacheView(pixel_view);
+ image_view=DestroyCacheView(image_view);
+ return(mean_image);
+}