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feature.c
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% FFFFF EEEEE AAA TTTTT U U RRRR EEEEE %
% F E A A T U U R R E %
% FFF EEE AAAAA T U U RRRR EEE %
% F E A A T U U R R E %
% F EEEEE A A T UUU R R EEEEE %
% %
% %
% MagickCore Image Feature Methods %
% %
% Software Design %
% Cristy %
% July 1992 %
% %
% %
% Copyright @ 1999 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 %
% %
% https://imagemagick.org/license/ %
% %
% Unless required by applicable law or agreed to in writing, software %
% distributed under the License is distributed on an "AS IS" BASIS, %
% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. %
% See the License for the specific language governing permissions and %
% limitations under the License. %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%
%
*/
␌
/*
Include declarations.
*/
#include "MagickCore/studio.h"
#include "MagickCore/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/colorspace.h"
#include "MagickCore/colorspace-private.h"
#include "MagickCore/composite.h"
#include "MagickCore/composite-private.h"
#include "MagickCore/compress.h"
#include "MagickCore/constitute.h"
#include "MagickCore/display.h"
#include "MagickCore/draw.h"
#include "MagickCore/enhance.h"
#include "MagickCore/exception.h"
#include "MagickCore/exception-private.h"
#include "MagickCore/feature.h"
#include "MagickCore/gem.h"
#include "MagickCore/geometry.h"
#include "MagickCore/list.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/nt-base-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"
#include "MagickCore/resource_.h"
#include "MagickCore/segment.h"
#include "MagickCore/semaphore.h"
#include "MagickCore/signature-private.h"
#include "MagickCore/statistic-private.h"
#include "MagickCore/string_.h"
#include "MagickCore/thread-private.h"
#include "MagickCore/timer.h"
#include "MagickCore/utility.h"
#include "MagickCore/utility-private.h"
#include "MagickCore/version.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_percent: 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;
Quantum
*q;
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
element;
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);
assert(exception != (ExceptionInfo *) NULL);
assert(exception->signature == MagickCoreSignature);
if (IsEventLogging() != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
/*
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=MorphologyImage(image,ConvolveMorphology,1,kernel_info,exception);
kernel_info=DestroyKernelInfo(kernel_info);
if (edge_image == (Image *) NULL)
return((Image *) NULL);
if (TransformImageColorspace(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) shared(status) \
magick_number_threads(edge_image,edge_image,edge_image->rows,1)
#endif
for (y=0; y < (ssize_t) edge_image->rows; y++)
{
const Quantum
*magick_restrict p;
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;
const Quantum
*magick_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) memset(&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+=(ptrdiff_t) 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,&element);
max=element.intensity;
min=element.intensity;
edge_view=AcquireAuthenticCacheView(edge_image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(status) \
magick_number_threads(edge_image,edge_image,edge_image->rows,1)
#endif
for (y=0; y < (ssize_t) edge_image->rows; y++)
{
Quantum
*magick_restrict q;
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=(Quantum) 0;
q+=(ptrdiff_t) 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++)
{
ssize_t
x;
if (status == MagickFalse)
continue;
for (x=0; x < (ssize_t) edge_image->columns; x++)
{
CannyInfo
pixel;
const Quantum
*magick_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 atomic
#endif
progress++;
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);
}
␌
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% G e t I m a g e F e a t u r e s %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% GetImageFeatures() returns features for each channel in the image in
% each of four directions (horizontal, vertical, left and right diagonals)
% for the specified distance. The features include the angular second
% moment, contrast, correlation, sum of squares: variance, inverse difference
% moment, sum average, sum variance, sum entropy, entropy, difference variance,
% difference entropy, information measures of correlation 1, information
% measures of correlation 2, and maximum correlation coefficient. You can
% access the red channel contrast, for example, like this:
%
% channel_features=GetImageFeatures(image,1,exception);
% contrast=channel_features[RedPixelChannel].contrast[0];
%
% Use MagickRelinquishMemory() to free the features buffer.
%
% The format of the GetImageFeatures method is:
%
% ChannelFeatures *GetImageFeatures(const Image *image,
% const size_t distance,ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the image.
%
% o distance: the distance.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickExport ChannelFeatures *GetImageFeatures(const Image *image,
const size_t distance,ExceptionInfo *exception)
{
typedef struct _ChannelStatistics
{
PixelInfo
direction[4]; /* horizontal, vertical, left and right diagonals */
} ChannelStatistics;
CacheView
*image_view;
ChannelFeatures
*channel_features;
ChannelStatistics
**cooccurrence,
correlation,
*density_x,
*density_xy,
*density_y,
entropy_x,
entropy_xy,
entropy_xy1,
entropy_xy2,
entropy_y,
mean,
**Q,
*sum,
sum_squares,
variance;
PixelPacket
gray,
*grays;
MagickBooleanType
status;
ssize_t
i,
r;
size_t
length;
unsigned int
number_grays;
assert(image != (Image *) NULL);
assert(image->signature == MagickCoreSignature);
if (IsEventLogging() != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
if ((image->columns < (distance+1)) || (image->rows < (distance+1)))
return((ChannelFeatures *) NULL);
length=MaxPixelChannels+1UL;
channel_features=(ChannelFeatures *) AcquireQuantumMemory(length,
sizeof(*channel_features));
if (channel_features == (ChannelFeatures *) NULL)
ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
(void) memset(channel_features,0,length*
sizeof(*channel_features));
/*
Form grays.
*/
grays=(PixelPacket *) AcquireQuantumMemory(MaxMap+1UL,sizeof(*grays));
if (grays == (PixelPacket *) NULL)
{
channel_features=(ChannelFeatures *) RelinquishMagickMemory(
channel_features);
(void) ThrowMagickException(exception,GetMagickModule(),
ResourceLimitError,"MemoryAllocationFailed","`%s'",image->filename);
return(channel_features);
}
for (i=0; i <= (ssize_t) MaxMap; i++)
{
grays[i].red=(~0U);
grays[i].green=(~0U);
grays[i].blue=(~0U);
grays[i].alpha=(~0U);
grays[i].black=(~0U);
}
status=MagickTrue;
image_view=AcquireVirtualCacheView(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(status) \
magick_number_threads(image,image,image->rows,1)
#endif
for (r=0; r < (ssize_t) image->rows; r++)
{
const Quantum
*magick_restrict p;
ssize_t
x;
if (status == MagickFalse)
continue;
p=GetCacheViewVirtualPixels(image_view,0,r,image->columns,1,exception);
if (p == (const Quantum *) NULL)
{
status=MagickFalse;
continue;
}
for (x=0; x < (ssize_t) image->columns; x++)
{
grays[ScaleQuantumToMap(GetPixelRed(image,p))].red=
ScaleQuantumToMap(GetPixelRed(image,p));
grays[ScaleQuantumToMap(GetPixelGreen(image,p))].green=
ScaleQuantumToMap(GetPixelGreen(image,p));
grays[ScaleQuantumToMap(GetPixelBlue(image,p))].blue=
ScaleQuantumToMap(GetPixelBlue(image,p));
if (image->colorspace == CMYKColorspace)
grays[ScaleQuantumToMap(GetPixelBlack(image,p))].black=
ScaleQuantumToMap(GetPixelBlack(image,p));
if (image->alpha_trait != UndefinedPixelTrait)
grays[ScaleQuantumToMap(GetPixelAlpha(image,p))].alpha=
ScaleQuantumToMap(GetPixelAlpha(image,p));
p+=(ptrdiff_t) GetPixelChannels(image);
}
}
image_view=DestroyCacheView(image_view);
if (status == MagickFalse)
{
grays=(PixelPacket *) RelinquishMagickMemory(grays);
channel_features=(ChannelFeatures *) RelinquishMagickMemory(
channel_features);
return(channel_features);
}
(void) memset(&gray,0,sizeof(gray));
for (i=0; i <= (ssize_t) MaxMap; i++)
{
if (grays[i].red != ~0U)
grays[gray.red++].red=grays[i].red;
if (grays[i].green != ~0U)
grays[gray.green++].green=grays[i].green;
if (grays[i].blue != ~0U)
grays[gray.blue++].blue=grays[i].blue;
if (image->colorspace == CMYKColorspace)
if (grays[i].black != ~0U)
grays[gray.black++].black=grays[i].black;
if (image->alpha_trait != UndefinedPixelTrait)
if (grays[i].alpha != ~0U)
grays[gray.alpha++].alpha=grays[i].alpha;
}
/*
Allocate spatial dependence matrix.
*/
number_grays=gray.red;
if (gray.green > number_grays)
number_grays=gray.green;
if (gray.blue > number_grays)
number_grays=gray.blue;
if (image->colorspace == CMYKColorspace)
if (gray.black > number_grays)
number_grays=gray.black;
if (image->alpha_trait != UndefinedPixelTrait)
if (gray.alpha > number_grays)
number_grays=gray.alpha;
cooccurrence=(ChannelStatistics **) AcquireQuantumMemory(number_grays,
sizeof(*cooccurrence));
density_x=(ChannelStatistics *) AcquireQuantumMemory(number_grays+1,
2*sizeof(*density_x));
density_xy=(ChannelStatistics *) AcquireQuantumMemory(number_grays+1,
2*sizeof(*density_xy));
density_y=(ChannelStatistics *) AcquireQuantumMemory(number_grays+1,
2*sizeof(*density_y));
Q=(ChannelStatistics **) AcquireQuantumMemory(number_grays,sizeof(*Q));
sum=(ChannelStatistics *) AcquireQuantumMemory(number_grays,sizeof(*sum));
if ((cooccurrence == (ChannelStatistics **) NULL) ||
(density_x == (ChannelStatistics *) NULL) ||
(density_xy == (ChannelStatistics *) NULL) ||
(density_y == (ChannelStatistics *) NULL) ||
(Q == (ChannelStatistics **) NULL) ||
(sum == (ChannelStatistics *) NULL))
{
if (Q != (ChannelStatistics **) NULL)
{
for (i=0; i < (ssize_t) number_grays; i++)
Q[i]=(ChannelStatistics *) RelinquishMagickMemory(Q[i]);
Q=(ChannelStatistics **) RelinquishMagickMemory(Q);
}
if (sum != (ChannelStatistics *) NULL)
sum=(ChannelStatistics *) RelinquishMagickMemory(sum);
if (density_y != (ChannelStatistics *) NULL)
density_y=(ChannelStatistics *) RelinquishMagickMemory(density_y);
if (density_xy != (ChannelStatistics *) NULL)
density_xy=(ChannelStatistics *) RelinquishMagickMemory(density_xy);
if (density_x != (ChannelStatistics *) NULL)
density_x=(ChannelStatistics *) RelinquishMagickMemory(density_x);
if (cooccurrence != (ChannelStatistics **) NULL)
{
for (i=0; i < (ssize_t) number_grays; i++)
cooccurrence[i]=(ChannelStatistics *)
RelinquishMagickMemory(cooccurrence[i]);
cooccurrence=(ChannelStatistics **) RelinquishMagickMemory(
cooccurrence);
}
grays=(PixelPacket *) RelinquishMagickMemory(grays);
channel_features=(ChannelFeatures *) RelinquishMagickMemory(
channel_features);
(void) ThrowMagickException(exception,GetMagickModule(),
ResourceLimitError,"MemoryAllocationFailed","`%s'",image->filename);
return(channel_features);
}
(void) memset(&correlation,0,sizeof(correlation));
(void) memset(density_x,0,2*(number_grays+1)*sizeof(*density_x));
(void) memset(density_xy,0,2*(number_grays+1)*sizeof(*density_xy));
(void) memset(density_y,0,2*(number_grays+1)*sizeof(*density_y));
(void) memset(&mean,0,sizeof(mean));
(void) memset(sum,0,number_grays*sizeof(*sum));
(void) memset(&sum_squares,0,sizeof(sum_squares));
(void) memset(density_xy,0,2*number_grays*sizeof(*density_xy));
(void) memset(&entropy_x,0,sizeof(entropy_x));
(void) memset(&entropy_xy,0,sizeof(entropy_xy));
(void) memset(&entropy_xy1,0,sizeof(entropy_xy1));
(void) memset(&entropy_xy2,0,sizeof(entropy_xy2));
(void) memset(&entropy_y,0,sizeof(entropy_y));
(void) memset(&variance,0,sizeof(variance));
for (i=0; i < (ssize_t) number_grays; i++)
{
cooccurrence[i]=(ChannelStatistics *) AcquireQuantumMemory(number_grays,
sizeof(**cooccurrence));
Q[i]=(ChannelStatistics *) AcquireQuantumMemory(number_grays,sizeof(**Q));
if ((cooccurrence[i] == (ChannelStatistics *) NULL) ||
(Q[i] == (ChannelStatistics *) NULL))
break;
(void) memset(cooccurrence[i],0,number_grays*
sizeof(**cooccurrence));
(void) memset(Q[i],0,number_grays*sizeof(**Q));
}
if (i < (ssize_t) number_grays)
{
for (i--; i >= 0; i--)
{
if (Q[i] != (ChannelStatistics *) NULL)
Q[i]=(ChannelStatistics *) RelinquishMagickMemory(Q[i]);
if (cooccurrence[i] != (ChannelStatistics *) NULL)
cooccurrence[i]=(ChannelStatistics *)
RelinquishMagickMemory(cooccurrence[i]);
}
Q=(ChannelStatistics **) RelinquishMagickMemory(Q);
cooccurrence=(ChannelStatistics **) RelinquishMagickMemory(cooccurrence);
sum=(ChannelStatistics *) RelinquishMagickMemory(sum);
density_y=(ChannelStatistics *) RelinquishMagickMemory(density_y);
density_xy=(ChannelStatistics *) RelinquishMagickMemory(density_xy);
density_x=(ChannelStatistics *) RelinquishMagickMemory(density_x);
grays=(PixelPacket *) RelinquishMagickMemory(grays);
channel_features=(ChannelFeatures *) RelinquishMagickMemory(
channel_features);
(void) ThrowMagickException(exception,GetMagickModule(),
ResourceLimitError,"MemoryAllocationFailed","`%s'",image->filename);
return(channel_features);
}
/*
Initialize spatial dependence matrix.
*/
status=MagickTrue;
image_view=AcquireVirtualCacheView(image,exception);
for (r=0; r < (ssize_t) image->rows; r++)
{
const Quantum
*magick_restrict p;
ssize_t
x;
ssize_t
offset,
u,
v;
if (status == MagickFalse)
continue;
p=GetCacheViewVirtualPixels(image_view,-(ssize_t) distance,r,image->columns+
2*distance,distance+2,exception);
if (p == (const Quantum *) NULL)
{
status=MagickFalse;
continue;
}
p+=(ptrdiff_t) distance*GetPixelChannels(image);;
for (x=0; x < (ssize_t) image->columns; x++)
{
for (i=0; i < 4; i++)
{
switch (i)
{
case 0:
default:
{
/*
Horizontal adjacency.
*/
offset=(ssize_t) distance;
break;
}
case 1:
{
/*
Vertical adjacency.
*/
offset=(ssize_t) (image->columns+2*distance);
break;
}
case 2:
{
/*
Right diagonal adjacency.
*/
offset=(ssize_t) ((image->columns+2*distance)-distance);
break;
}
case 3:
{
/*
Left diagonal adjacency.
*/
offset=(ssize_t) ((image->columns+2*distance)+distance);
break;
}
}
u=0;
v=0;
while (grays[u].red != ScaleQuantumToMap(GetPixelRed(image,p)))
u++;
while (grays[v].red != ScaleQuantumToMap(GetPixelRed(image,p+offset*(ssize_t) GetPixelChannels(image))))
v++;
cooccurrence[u][v].direction[i].red++;
cooccurrence[v][u].direction[i].red++;
u=0;
v=0;
while (grays[u].green != ScaleQuantumToMap(GetPixelGreen(image,p)))
u++;
while (grays[v].green != ScaleQuantumToMap(GetPixelGreen(image,p+offset*(ssize_t) GetPixelChannels(image))))
v++;
cooccurrence[u][v].direction[i].green++;
cooccurrence[v][u].direction[i].green++;
u=0;
v=0;
while (grays[u].blue != ScaleQuantumToMap(GetPixelBlue(image,p)))
u++;
while (grays[v].blue != ScaleQuantumToMap(GetPixelBlue(image,p+offset*(ssize_t) GetPixelChannels(image))))
v++;
cooccurrence[u][v].direction[i].blue++;
cooccurrence[v][u].direction[i].blue++;
if (image->colorspace == CMYKColorspace)
{
u=0;
v=0;
while (grays[u].black != ScaleQuantumToMap(GetPixelBlack(image,p)))
u++;
while (grays[v].black != ScaleQuantumToMap(GetPixelBlack(image,p+offset*(ssize_t) GetPixelChannels(image))))
v++;
cooccurrence[u][v].direction[i].black++;
cooccurrence[v][u].direction[i].black++;
}
if (image->alpha_trait != UndefinedPixelTrait)
{
u=0;
v=0;
while (grays[u].alpha != ScaleQuantumToMap(GetPixelAlpha(image,p)))
u++;
while (grays[v].alpha != ScaleQuantumToMap(GetPixelAlpha(image,p+offset*(ssize_t) GetPixelChannels(image))))
v++;
cooccurrence[u][v].direction[i].alpha++;
cooccurrence[v][u].direction[i].alpha++;
}
}
p+=(ptrdiff_t) GetPixelChannels(image);
}
}
grays=(PixelPacket *) RelinquishMagickMemory(grays);
image_view=DestroyCacheView(image_view);
if (status == MagickFalse)
{
for (i=0; i < (ssize_t) number_grays; i++)
cooccurrence[i]=(ChannelStatistics *)
RelinquishMagickMemory(cooccurrence[i]);
cooccurrence=(ChannelStatistics **) RelinquishMagickMemory(cooccurrence);
channel_features=(ChannelFeatures *) RelinquishMagickMemory(
channel_features);
(void) ThrowMagickException(exception,GetMagickModule(),
ResourceLimitError,"MemoryAllocationFailed","`%s'",image->filename);
return(channel_features);
}
/*
Normalize spatial dependence matrix.
*/
for (i=0; i < 4; i++)
{
double
normalize;
ssize_t
y;
switch (i)
{
case 0:
default:
{
/*
Horizontal adjacency.
*/
normalize=2.0*image->rows*(image->columns-distance);
break;
}
case 1:
{
/*
Vertical adjacency.
*/
normalize=2.0*(image->rows-distance)*image->columns;
break;
}
case 2:
{
/*
Right diagonal adjacency.
*/
normalize=2.0*(image->rows-distance)*(image->columns-distance);
break;
}
case 3:
{
/*
Left diagonal adjacency.
*/
normalize=2.0*(image->rows-distance)*(image->columns-distance);
break;
}
}
normalize=MagickSafeReciprocal(normalize);
for (y=0; y < (ssize_t) number_grays; y++)
{
ssize_t
x;
for (x=0; x < (ssize_t) number_grays; x++)
{
cooccurrence[x][y].direction[i].red*=normalize;
cooccurrence[x][y].direction[i].green*=normalize;
cooccurrence[x][y].direction[i].blue*=normalize;
if (image->colorspace == CMYKColorspace)
cooccurrence[x][y].direction[i].black*=normalize;
if (image->alpha_trait != UndefinedPixelTrait)
cooccurrence[x][y].direction[i].alpha*=normalize;
}
}
}
/*
Compute texture features.
*/
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(status) \
magick_number_threads(image,image,number_grays,1)
#endif
for (i=0; i < 4; i++)
{
ssize_t
y;
for (y=0; y < (ssize_t) number_grays; y++)
{
ssize_t
x;
for (x=0; x < (ssize_t) number_grays; x++)
{
/*
Angular second moment: measure of homogeneity of the image.
*/
channel_features[RedPixelChannel].angular_second_moment[i]+=
cooccurrence[x][y].direction[i].red*
cooccurrence[x][y].direction[i].red;
channel_features[GreenPixelChannel].angular_second_moment[i]+=
cooccurrence[x][y].direction[i].green*
cooccurrence[x][y].direction[i].green;
channel_features[BluePixelChannel].angular_second_moment[i]+=
cooccurrence[x][y].direction[i].blue*
cooccurrence[x][y].direction[i].blue;
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].angular_second_moment[i]+=
cooccurrence[x][y].direction[i].black*
cooccurrence[x][y].direction[i].black;
if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].angular_second_moment[i]+=
cooccurrence[x][y].direction[i].alpha*
cooccurrence[x][y].direction[i].alpha;
/*
Correlation: measure of linear-dependencies in the image.
*/
sum[y].direction[i].red+=cooccurrence[x][y].direction[i].red;
sum[y].direction[i].green+=cooccurrence[x][y].direction[i].green;
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 != 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*
cooccurrence[x][y].direction[i].green;
correlation.direction[i].blue+=x*y*
cooccurrence[x][y].direction[i].blue;
if (image->colorspace == CMYKColorspace)
correlation.direction[i].black+=x*y*
cooccurrence[x][y].direction[i].black;
if (image->alpha_trait != UndefinedPixelTrait)
correlation.direction[i].alpha+=x*y*
cooccurrence[x][y].direction[i].alpha;
/*
Inverse Difference Moment.
*/
channel_features[RedPixelChannel].inverse_difference_moment[i]+=
cooccurrence[x][y].direction[i].red/((y-x)*(y-x)+1);
channel_features[GreenPixelChannel].inverse_difference_moment[i]+=
cooccurrence[x][y].direction[i].green/((y-x)*(y-x)+1);
channel_features[BluePixelChannel].inverse_difference_moment[i]+=
cooccurrence[x][y].direction[i].blue/((y-x)*(y-x)+1);
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 != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].inverse_difference_moment[i]+=
cooccurrence[x][y].direction[i].alpha/((y-x)*(y-x)+1);
/*
Sum average.
*/
density_xy[y+x+2].direction[i].red+=
cooccurrence[x][y].direction[i].red;
density_xy[y+x+2].direction[i].green+=
cooccurrence[x][y].direction[i].green;
density_xy[y+x+2].direction[i].blue+=
cooccurrence[x][y].direction[i].blue;
if (image->colorspace == CMYKColorspace)
density_xy[y+x+2].direction[i].black+=
cooccurrence[x][y].direction[i].black;
if (image->alpha_trait != UndefinedPixelTrait)
density_xy[y+x+2].direction[i].alpha+=
cooccurrence[x][y].direction[i].alpha;
/*
Entropy.
*/
channel_features[RedPixelChannel].entropy[i]-=
cooccurrence[x][y].direction[i].red*
log2(cooccurrence[x][y].direction[i].red);
channel_features[GreenPixelChannel].entropy[i]-=
cooccurrence[x][y].direction[i].green*
log2(cooccurrence[x][y].direction[i].green);
channel_features[BluePixelChannel].entropy[i]-=
cooccurrence[x][y].direction[i].blue*
log2(cooccurrence[x][y].direction[i].blue);
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].entropy[i]-=
cooccurrence[x][y].direction[i].black*
log2(cooccurrence[x][y].direction[i].black);
if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].entropy[i]-=
cooccurrence[x][y].direction[i].alpha*
log2(cooccurrence[x][y].direction[i].alpha);
/*
Information Measures of Correlation.
*/
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 != UndefinedPixelTrait)
density_x[x].direction[i].alpha+=
cooccurrence[x][y].direction[i].alpha;
if (image->colorspace == CMYKColorspace)
density_x[x].direction[i].black+=
cooccurrence[x][y].direction[i].black;
density_y[y].direction[i].red+=cooccurrence[x][y].direction[i].red;
density_y[y].direction[i].green+=cooccurrence[x][y].direction[i].green;
density_y[y].direction[i].blue+=cooccurrence[x][y].direction[i].blue;
if (image->colorspace == CMYKColorspace)
density_y[y].direction[i].black+=
cooccurrence[x][y].direction[i].black;
if (image->alpha_trait != UndefinedPixelTrait)
density_y[y].direction[i].alpha+=
cooccurrence[x][y].direction[i].alpha;
}
mean.direction[i].red+=y*sum[y].direction[i].red;
sum_squares.direction[i].red+=y*y*sum[y].direction[i].red;
mean.direction[i].green+=y*sum[y].direction[i].green;
sum_squares.direction[i].green+=y*y*sum[y].direction[i].green;
mean.direction[i].blue+=y*sum[y].direction[i].blue;
sum_squares.direction[i].blue+=y*y*sum[y].direction[i].blue;
if (image->colorspace == CMYKColorspace)
{
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 != UndefinedPixelTrait)
{
mean.direction[i].alpha+=y*sum[y].direction[i].alpha;
sum_squares.direction[i].alpha+=y*y*sum[y].direction[i].alpha;
}
}
/*
Correlation: measure of linear-dependencies in the image.
*/
channel_features[RedPixelChannel].correlation[i]=
(correlation.direction[i].red-mean.direction[i].red*
mean.direction[i].red)/(sqrt(sum_squares.direction[i].red-
(mean.direction[i].red*mean.direction[i].red))*sqrt(
sum_squares.direction[i].red-(mean.direction[i].red*
mean.direction[i].red)));
channel_features[GreenPixelChannel].correlation[i]=
(correlation.direction[i].green-mean.direction[i].green*
mean.direction[i].green)/(sqrt(sum_squares.direction[i].green-
(mean.direction[i].green*mean.direction[i].green))*sqrt(
sum_squares.direction[i].green-(mean.direction[i].green*
mean.direction[i].green)));
channel_features[BluePixelChannel].correlation[i]=
(correlation.direction[i].blue-mean.direction[i].blue*
mean.direction[i].blue)/(sqrt(sum_squares.direction[i].blue-
(mean.direction[i].blue*mean.direction[i].blue))*sqrt(
sum_squares.direction[i].blue-(mean.direction[i].blue*
mean.direction[i].blue)));
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].correlation[i]=
(correlation.direction[i].black-mean.direction[i].black*
mean.direction[i].black)/(sqrt(sum_squares.direction[i].black-
(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 != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].correlation[i]=
(correlation.direction[i].alpha-mean.direction[i].alpha*
mean.direction[i].alpha)/(sqrt(sum_squares.direction[i].alpha-
(mean.direction[i].alpha*mean.direction[i].alpha))*sqrt(
sum_squares.direction[i].alpha-(mean.direction[i].alpha*
mean.direction[i].alpha)));
}
/*
Compute more texture features.
*/
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(status) \
magick_number_threads(image,image,number_grays,1)
#endif
for (i=0; i < 4; i++)
{
ssize_t
x;
for (x=2; x < (ssize_t) (2*number_grays); x++)
{
/*
Sum average.
*/
channel_features[RedPixelChannel].sum_average[i]+=
x*density_xy[x].direction[i].red;
channel_features[GreenPixelChannel].sum_average[i]+=
x*density_xy[x].direction[i].green;
channel_features[BluePixelChannel].sum_average[i]+=
x*density_xy[x].direction[i].blue;
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].sum_average[i]+=
x*density_xy[x].direction[i].black;
if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].sum_average[i]+=
x*density_xy[x].direction[i].alpha;
/*
Sum entropy.
*/
channel_features[RedPixelChannel].sum_entropy[i]-=
density_xy[x].direction[i].red*
log2(density_xy[x].direction[i].red);
channel_features[GreenPixelChannel].sum_entropy[i]-=
density_xy[x].direction[i].green*
log2(density_xy[x].direction[i].green);
channel_features[BluePixelChannel].sum_entropy[i]-=
density_xy[x].direction[i].blue*
log2(density_xy[x].direction[i].blue);
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].sum_entropy[i]-=
density_xy[x].direction[i].black*
log2(density_xy[x].direction[i].black);
if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].sum_entropy[i]-=
density_xy[x].direction[i].alpha*
log2(density_xy[x].direction[i].alpha);
/*
Sum variance.
*/
channel_features[RedPixelChannel].sum_variance[i]+=
(x-channel_features[RedPixelChannel].sum_entropy[i])*
(x-channel_features[RedPixelChannel].sum_entropy[i])*
density_xy[x].direction[i].red;
channel_features[GreenPixelChannel].sum_variance[i]+=
(x-channel_features[GreenPixelChannel].sum_entropy[i])*
(x-channel_features[GreenPixelChannel].sum_entropy[i])*
density_xy[x].direction[i].green;
channel_features[BluePixelChannel].sum_variance[i]+=
(x-channel_features[BluePixelChannel].sum_entropy[i])*
(x-channel_features[BluePixelChannel].sum_entropy[i])*
density_xy[x].direction[i].blue;
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].sum_variance[i]+=
(x-channel_features[BlackPixelChannel].sum_entropy[i])*
(x-channel_features[BlackPixelChannel].sum_entropy[i])*
density_xy[x].direction[i].black;
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])*
density_xy[x].direction[i].alpha;
}
}
/*
Compute more texture features.
*/
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(status) \
magick_number_threads(image,image,number_grays,1)
#endif
for (i=0; i < 4; i++)
{
ssize_t
y;
for (y=0; y < (ssize_t) number_grays; y++)
{
ssize_t
x;
for (x=0; x < (ssize_t) number_grays; x++)
{
/*
Sum of Squares: Variance
*/
variance.direction[i].red+=(y-mean.direction[i].red+1)*
(y-mean.direction[i].red+1)*cooccurrence[x][y].direction[i].red;
variance.direction[i].green+=(y-mean.direction[i].green+1)*
(y-mean.direction[i].green+1)*cooccurrence[x][y].direction[i].green;
variance.direction[i].blue+=(y-mean.direction[i].blue+1)*
(y-mean.direction[i].blue+1)*cooccurrence[x][y].direction[i].blue;
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 != UndefinedPixelTrait)
variance.direction[i].alpha+=(y-mean.direction[i].alpha+1)*
(y-mean.direction[i].alpha+1)*
cooccurrence[x][y].direction[i].alpha;
/*
Sum average / Difference Variance.
*/
density_xy[MagickAbsoluteValue(y-x)].direction[i].red+=
cooccurrence[x][y].direction[i].red;
density_xy[MagickAbsoluteValue(y-x)].direction[i].green+=
cooccurrence[x][y].direction[i].green;
density_xy[MagickAbsoluteValue(y-x)].direction[i].blue+=
cooccurrence[x][y].direction[i].blue;
if (image->colorspace == CMYKColorspace)
density_xy[MagickAbsoluteValue(y-x)].direction[i].black+=
cooccurrence[x][y].direction[i].black;
if (image->alpha_trait != UndefinedPixelTrait)
density_xy[MagickAbsoluteValue(y-x)].direction[i].alpha+=
cooccurrence[x][y].direction[i].alpha;
/*
Information Measures of Correlation.
*/
entropy_xy.direction[i].red-=cooccurrence[x][y].direction[i].red*
log2(cooccurrence[x][y].direction[i].red);
entropy_xy.direction[i].green-=cooccurrence[x][y].direction[i].green*
log2(cooccurrence[x][y].direction[i].green);
entropy_xy.direction[i].blue-=cooccurrence[x][y].direction[i].blue*
log2(cooccurrence[x][y].direction[i].blue);
if (image->colorspace == CMYKColorspace)
entropy_xy.direction[i].black-=cooccurrence[x][y].direction[i].black*
log2(cooccurrence[x][y].direction[i].black);
if (image->alpha_trait != UndefinedPixelTrait)
entropy_xy.direction[i].alpha-=
cooccurrence[x][y].direction[i].alpha*log2(
cooccurrence[x][y].direction[i].alpha);
entropy_xy1.direction[i].red-=(cooccurrence[x][y].direction[i].red*
log2(density_x[x].direction[i].red*density_y[y].direction[i].red));
entropy_xy1.direction[i].green-=(cooccurrence[x][y].direction[i].green*
log2(density_x[x].direction[i].green*
density_y[y].direction[i].green));
entropy_xy1.direction[i].blue-=(cooccurrence[x][y].direction[i].blue*
log2(density_x[x].direction[i].blue*density_y[y].direction[i].blue));
if (image->colorspace == CMYKColorspace)
entropy_xy1.direction[i].black-=(
cooccurrence[x][y].direction[i].black*log2(
density_x[x].direction[i].black*density_y[y].direction[i].black));
if (image->alpha_trait != UndefinedPixelTrait)
entropy_xy1.direction[i].alpha-=(
cooccurrence[x][y].direction[i].alpha*log2(
density_x[x].direction[i].alpha*density_y[y].direction[i].alpha));
entropy_xy2.direction[i].red-=(density_x[x].direction[i].red*
density_y[y].direction[i].red*log2(density_x[x].direction[i].red*
density_y[y].direction[i].red));
entropy_xy2.direction[i].green-=(density_x[x].direction[i].green*
density_y[y].direction[i].green*log2(density_x[x].direction[i].green*
density_y[y].direction[i].green));
entropy_xy2.direction[i].blue-=(density_x[x].direction[i].blue*
density_y[y].direction[i].blue*log2(density_x[x].direction[i].blue*
density_y[y].direction[i].blue));
if (image->colorspace == CMYKColorspace)
entropy_xy2.direction[i].black-=(density_x[x].direction[i].black*
density_y[y].direction[i].black*log2(
density_x[x].direction[i].black*density_y[y].direction[i].black));
if (image->alpha_trait != UndefinedPixelTrait)
entropy_xy2.direction[i].alpha-=(density_x[x].direction[i].alpha*
density_y[y].direction[i].alpha*log2(
density_x[x].direction[i].alpha*density_y[y].direction[i].alpha));
}
}
channel_features[RedPixelChannel].variance_sum_of_squares[i]=
variance.direction[i].red;
channel_features[GreenPixelChannel].variance_sum_of_squares[i]=
variance.direction[i].green;
channel_features[BluePixelChannel].variance_sum_of_squares[i]=
variance.direction[i].blue;
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].variance_sum_of_squares[i]=
variance.direction[i].black;
if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].variance_sum_of_squares[i]=
variance.direction[i].alpha;
}
/*
Compute more texture features.
*/
(void) memset(&variance,0,sizeof(variance));
(void) memset(&sum_squares,0,sizeof(sum_squares));
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(status) \
magick_number_threads(image,image,number_grays,1)
#endif
for (i=0; i < 4; i++)
{
ssize_t
x;
for (x=0; x < (ssize_t) number_grays; x++)
{
/*
Difference variance.
*/
variance.direction[i].red+=density_xy[x].direction[i].red;
variance.direction[i].green+=density_xy[x].direction[i].green;
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 != 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;
sum_squares.direction[i].green+=density_xy[x].direction[i].green*
density_xy[x].direction[i].green;
sum_squares.direction[i].blue+=density_xy[x].direction[i].blue*
density_xy[x].direction[i].blue;
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 != UndefinedPixelTrait)
sum_squares.direction[i].alpha+=density_xy[x].direction[i].alpha*
density_xy[x].direction[i].alpha;
/*
Difference entropy.
*/
channel_features[RedPixelChannel].difference_entropy[i]-=
density_xy[x].direction[i].red*
log2(density_xy[x].direction[i].red);
channel_features[GreenPixelChannel].difference_entropy[i]-=
density_xy[x].direction[i].green*
log2(density_xy[x].direction[i].green);
channel_features[BluePixelChannel].difference_entropy[i]-=
density_xy[x].direction[i].blue*
log2(density_xy[x].direction[i].blue);
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].difference_entropy[i]-=
density_xy[x].direction[i].black*
log2(density_xy[x].direction[i].black);
if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].difference_entropy[i]-=
density_xy[x].direction[i].alpha*
log2(density_xy[x].direction[i].alpha);
/*
Information Measures of Correlation.
*/
entropy_x.direction[i].red-=(density_x[x].direction[i].red*
log2(density_x[x].direction[i].red));
entropy_x.direction[i].green-=(density_x[x].direction[i].green*
log2(density_x[x].direction[i].green));
entropy_x.direction[i].blue-=(density_x[x].direction[i].blue*
log2(density_x[x].direction[i].blue));
if (image->colorspace == CMYKColorspace)
entropy_x.direction[i].black-=(density_x[x].direction[i].black*
log2(density_x[x].direction[i].black));
if (image->alpha_trait != UndefinedPixelTrait)
entropy_x.direction[i].alpha-=(density_x[x].direction[i].alpha*
log2(density_x[x].direction[i].alpha));
entropy_y.direction[i].red-=(density_y[x].direction[i].red*
log2(density_y[x].direction[i].red));
entropy_y.direction[i].green-=(density_y[x].direction[i].green*
log2(density_y[x].direction[i].green));
entropy_y.direction[i].blue-=(density_y[x].direction[i].blue*
log2(density_y[x].direction[i].blue));
if (image->colorspace == CMYKColorspace)
entropy_y.direction[i].black-=(density_y[x].direction[i].black*
log2(density_y[x].direction[i].black));
if (image->alpha_trait != UndefinedPixelTrait)
entropy_y.direction[i].alpha-=(density_y[x].direction[i].alpha*
log2(density_y[x].direction[i].alpha));
}
/*
Difference variance.
*/
channel_features[RedPixelChannel].difference_variance[i]=
(((double) number_grays*number_grays*sum_squares.direction[i].red)-
(variance.direction[i].red*variance.direction[i].red))/
((double) number_grays*number_grays*number_grays*number_grays);
channel_features[GreenPixelChannel].difference_variance[i]=
(((double) number_grays*number_grays*sum_squares.direction[i].green)-
(variance.direction[i].green*variance.direction[i].green))/
((double) number_grays*number_grays*number_grays*number_grays);
channel_features[BluePixelChannel].difference_variance[i]=
(((double) number_grays*number_grays*sum_squares.direction[i].blue)-
(variance.direction[i].blue*variance.direction[i].blue))/
((double) number_grays*number_grays*number_grays*number_grays);
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].difference_variance[i]=
(((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 != 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))/
((double) number_grays*number_grays*number_grays*number_grays);
/*
Information Measures of Correlation.
*/
channel_features[RedPixelChannel].measure_of_correlation_1[i]=
(entropy_xy.direction[i].red-entropy_xy1.direction[i].red)/
(entropy_x.direction[i].red > entropy_y.direction[i].red ?
entropy_x.direction[i].red : entropy_y.direction[i].red);
channel_features[GreenPixelChannel].measure_of_correlation_1[i]=
(entropy_xy.direction[i].green-entropy_xy1.direction[i].green)/
(entropy_x.direction[i].green > entropy_y.direction[i].green ?
entropy_x.direction[i].green : entropy_y.direction[i].green);
channel_features[BluePixelChannel].measure_of_correlation_1[i]=
(entropy_xy.direction[i].blue-entropy_xy1.direction[i].blue)/
(entropy_x.direction[i].blue > entropy_y.direction[i].blue ?
entropy_x.direction[i].blue : entropy_y.direction[i].blue);
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].measure_of_correlation_1[i]=
(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 != 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*(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*(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*(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*(double) (entropy_xy2.direction[i].black-
entropy_xy.direction[i].black)))));
if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].measure_of_correlation_2[i]=
(sqrt(fabs(1.0-exp(-2.0*(double) (entropy_xy2.direction[i].alpha-
entropy_xy.direction[i].alpha)))));
}
/*
Compute more texture features.
*/
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(status) \
magick_number_threads(image,image,number_grays,1)
#endif
for (i=0; i < 4; i++)
{
ssize_t
z;
for (z=0; z < (ssize_t) number_grays; z++)
{
ssize_t
y;
ChannelStatistics
pixel;
(void) memset(&pixel,0,sizeof(pixel));
for (y=0; y < (ssize_t) number_grays; y++)
{
ssize_t
x;
for (x=0; x < (ssize_t) number_grays; x++)
{
/*
Contrast: amount of local variations present in an image.
*/
if (((y-x) == z) || ((x-y) == z))
{
pixel.direction[i].red+=cooccurrence[x][y].direction[i].red;
pixel.direction[i].green+=cooccurrence[x][y].direction[i].green;
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 != UndefinedPixelTrait)
pixel.direction[i].alpha+=
cooccurrence[x][y].direction[i].alpha;
}
/*
Maximum Correlation Coefficient.
*/
if ((fabs(density_x[z].direction[i].red) > MagickEpsilon) &&
(fabs(density_y[x].direction[i].red) > MagickEpsilon))
Q[z][y].direction[i].red+=cooccurrence[z][x].direction[i].red*
cooccurrence[y][x].direction[i].red/density_x[z].direction[i].red/
density_y[x].direction[i].red;
if ((fabs(density_x[z].direction[i].green) > MagickEpsilon) &&
(fabs(density_y[x].direction[i].red) > MagickEpsilon))
Q[z][y].direction[i].green+=cooccurrence[z][x].direction[i].green*
cooccurrence[y][x].direction[i].green/
density_x[z].direction[i].green/density_y[x].direction[i].red;
if ((fabs(density_x[z].direction[i].blue) > MagickEpsilon) &&
(fabs(density_y[x].direction[i].blue) > MagickEpsilon))
Q[z][y].direction[i].blue+=cooccurrence[z][x].direction[i].blue*
cooccurrence[y][x].direction[i].blue/
density_x[z].direction[i].blue/density_y[x].direction[i].blue;
if (image->colorspace == CMYKColorspace)
if ((fabs(density_x[z].direction[i].black) > MagickEpsilon) &&
(fabs(density_y[x].direction[i].black) > MagickEpsilon))
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 != UndefinedPixelTrait)
if ((fabs(density_x[z].direction[i].alpha) > MagickEpsilon) &&
(fabs(density_y[x].direction[i].alpha) > MagickEpsilon))
Q[z][y].direction[i].alpha+=
cooccurrence[z][x].direction[i].alpha*
cooccurrence[y][x].direction[i].alpha/
density_x[z].direction[i].alpha/
density_y[x].direction[i].alpha;
}
}
channel_features[RedPixelChannel].contrast[i]+=z*z*
pixel.direction[i].red;
channel_features[GreenPixelChannel].contrast[i]+=z*z*
pixel.direction[i].green;
channel_features[BluePixelChannel].contrast[i]+=z*z*
pixel.direction[i].blue;
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].contrast[i]+=z*z*
pixel.direction[i].black;
if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].contrast[i]+=z*z*
pixel.direction[i].alpha;
}
/*
Maximum Correlation Coefficient.
Future: return second largest eigenvalue of Q.
*/
channel_features[RedPixelChannel].maximum_correlation_coefficient[i]=
sqrt(-1.0);
channel_features[GreenPixelChannel].maximum_correlation_coefficient[i]=
sqrt(-1.0);
channel_features[BluePixelChannel].maximum_correlation_coefficient[i]=
sqrt(-1.0);
if (image->colorspace == CMYKColorspace)
channel_features[BlackPixelChannel].maximum_correlation_coefficient[i]=
sqrt(-1.0);
if (image->alpha_trait != UndefinedPixelTrait)
channel_features[AlphaPixelChannel].maximum_correlation_coefficient[i]=
sqrt(-1.0);
}
/*
Relinquish resources.
*/
sum=(ChannelStatistics *) RelinquishMagickMemory(sum);
for (i=0; i < (ssize_t) number_grays; i++)
Q[i]=(ChannelStatistics *) RelinquishMagickMemory(Q[i]);
Q=(ChannelStatistics **) RelinquishMagickMemory(Q);
density_y=(ChannelStatistics *) RelinquishMagickMemory(density_y);
density_xy=(ChannelStatistics *) RelinquishMagickMemory(density_xy);
density_x=(ChannelStatistics *) RelinquishMagickMemory(density_x);
for (i=0; i < (ssize_t) number_grays; i++)
cooccurrence[i]=(ChannelStatistics *)
RelinquishMagickMemory(cooccurrence[i]);
cooccurrence=(ChannelStatistics **) RelinquishMagickMemory(cooccurrence);
return(channel_features);
}
␌
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% H o u g h L i n e I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% HoughLineImage() can be used in conjunction with any binary edge extracted
% image (we recommend 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));
}
static Image *RenderHoughLines(const ImageInfo *image_info,const size_t columns,
const size_t rows,ExceptionInfo *exception)
{
#define BoundingBox "viewbox"
DrawInfo
*draw_info;
Image
*image;
MagickBooleanType
status;
/*
Open image.
*/
image=AcquireImage(image_info,exception);
status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
if (status == MagickFalse)
{
image=DestroyImageList(image);
return((Image *) NULL);
}
image->columns=columns;
image->rows=rows;
draw_info=CloneDrawInfo(image_info,(DrawInfo *) NULL);
draw_info->affine.sx=image->resolution.x == 0.0 ? 1.0 : image->resolution.x/
DefaultResolution;
draw_info->affine.sy=image->resolution.y == 0.0 ? 1.0 : image->resolution.y/
DefaultResolution;
image->columns=CastDoubleToSizeT(draw_info->affine.sx*image->columns);
image->rows=CastDoubleToSizeT(draw_info->affine.sy*image->rows);
status=SetImageExtent(image,image->columns,image->rows,exception);
if (status == MagickFalse)
return(DestroyImageList(image));
if (SetImageBackgroundColor(image,exception) == MagickFalse)
{
image=DestroyImageList(image);
return((Image *) NULL);
}
/*
Render drawing.
*/
if (GetBlobStreamData(image) == (unsigned char *) NULL)
draw_info->primitive=FileToString(image->filename,~0UL,exception);
else
{
draw_info->primitive=(char *) AcquireQuantumMemory(1,(size_t)
GetBlobSize(image)+1);
if (draw_info->primitive != (char *) NULL)
{
(void) memcpy(draw_info->primitive,GetBlobStreamData(image),
(size_t) GetBlobSize(image));
draw_info->primitive[GetBlobSize(image)]='\0';
}
}
(void) DrawImage(image,draw_info,exception);
draw_info=DestroyDrawInfo(draw_info);
if (CloseBlob(image) == MagickFalse)
image=DestroyImageList(image);
return(GetFirstImageInList(image));
}
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;
ssize_t
y;
size_t
accumulator_height,
accumulator_width,
line_count;
/*
Create the accumulator.
*/
assert(image != (const Image *) NULL);
assert(image->signature == MagickCoreSignature);
assert(exception != (ExceptionInfo *) NULL);
assert(exception->signature == MagickCoreSignature);
if (IsEventLogging() != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
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++)
{
const Quantum
*magick_restrict p;
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) > ((double) QuantumRange/2.0))
{
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+=(ptrdiff_t) GetPixelChannels(image);
}
if (image->progress_monitor != (MagickProgressMonitor) NULL)
{
MagickBooleanType
proceed;
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp atomic
#endif
progress++;
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;
(void) FormatLocaleString(message,MagickPathExtent,
"# x1,y1 x2,y2 # count angle distance\n");
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++)
{
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 %g %g\n",line.x1,line.y1,line.x2,line.y2,
maxima,(double) x,(double) y);
if (write(file,message,strlen(message)) != (ssize_t) strlen(message))
status=MagickFalse;
}
}
}
(void) close_utf8(file);
/*
Render lines to image canvas.
*/
image_info=AcquireImageInfo();
image_info->background_color=image->background_color;
(void) FormatLocaleString(image_info->filename,MagickPathExtent,"%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=RenderHoughLines(image_info,image->columns,image->rows,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));
}
␌
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% 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);
assert(exception != (ExceptionInfo *) NULL);
assert(exception->signature == MagickCoreSignature);
if (IsEventLogging() != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
mean_image=CloneImage(image,0,0,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) shared(status,progress) \
magick_number_threads(mean_image,mean_image,mean_image->rows,1)
#endif
for (y=0; y < (ssize_t) mean_image->rows; y++)
{
const Quantum
*magick_restrict p;
Quantum
*magick_restrict q;
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;
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 = 1.0;
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++;
}
}
}
}
if (count != 0)
gamma=MagickSafeReciprocal((double) 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+=(ptrdiff_t) GetPixelChannels(image);
q+=(ptrdiff_t) 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 atomic
#endif
progress++;
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);
}
_CannyInfo
Definition feature.c:137
_ChannelStatistics
Definition statistic.h:30