king
/
v811_spc009
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
Branches Tags
${ item.name }
Create tag ${ searchTerm }
Create branch ${ searchTerm }
from 'main'
${ noResults }
v811_spc009/external/ImageMagick/MagickCore/threshold.c

2649 lines
82 KiB
Raw Permalink Blame History Escape

This file contains invisible Unicode characters!

This file contains invisible Unicode characters that may be processed differently from what appears below. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to reveal hidden characters.

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% TTTTT H H RRRR EEEEE SSSSS H H OOO L DDDD %
% T H H R R E SS H H O O L D D %
% T HHHHH RRRR EEE SSS HHHHH O O L D D %
% T H H R R E SS H H O O L D D %
% T H H R R EEEEE SSSSS H H OOO LLLLL DDDD %
% %
% %
% MagickCore Image Threshold Methods %
% %
% Software Design %
% Cristy %
% October 1996 %
% %
% %
% Copyright 1999-2021 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/script/license.php %
% %
% Unless required by applicable law or agreed to in writing, software %
% distributed under the License is distributed on an "AS IS" BASIS, %
% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. %
% See the License for the specific language governing permissions and %
% limitations under the License. %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%
%
*/
/*
Include declarations.
*/
#include "MagickCore/studio.h"
#include "MagickCore/artifact.h"
#include "MagickCore/blob.h"
#include "MagickCore/cache-view.h"
#include "MagickCore/color.h"
#include "MagickCore/color-private.h"
#include "MagickCore/colormap.h"
#include "MagickCore/colorspace.h"
#include "MagickCore/colorspace-private.h"
#include "MagickCore/configure.h"
#include "MagickCore/constitute.h"
#include "MagickCore/decorate.h"
#include "MagickCore/draw.h"
#include "MagickCore/enhance.h"
#include "MagickCore/exception.h"
#include "MagickCore/exception-private.h"
#include "MagickCore/effect.h"
#include "MagickCore/fx.h"
#include "MagickCore/gem.h"
#include "MagickCore/gem-private.h"
#include "MagickCore/geometry.h"
#include "MagickCore/image-private.h"
#include "MagickCore/list.h"
#include "MagickCore/log.h"
#include "MagickCore/memory_.h"
#include "MagickCore/monitor.h"
#include "MagickCore/monitor-private.h"
#include "MagickCore/montage.h"
#include "MagickCore/option.h"
#include "MagickCore/pixel-accessor.h"
#include "MagickCore/pixel-private.h"
#include "MagickCore/property.h"
#include "MagickCore/quantize.h"
#include "MagickCore/quantum.h"
#include "MagickCore/quantum-private.h"
#include "MagickCore/random_.h"
#include "MagickCore/random-private.h"
#include "MagickCore/resize.h"
#include "MagickCore/resource_.h"
#include "MagickCore/segment.h"
#include "MagickCore/shear.h"
#include "MagickCore/signature-private.h"
#include "MagickCore/string_.h"
#include "MagickCore/string-private.h"
#include "MagickCore/thread-private.h"
#include "MagickCore/threshold.h"
#include "MagickCore/token.h"
#include "MagickCore/transform.h"
#include "MagickCore/xml-tree.h"
#include "MagickCore/xml-tree-private.h"
/*
Define declarations.
*/
#define ThresholdsFilename "thresholds.xml"
/*
Typedef declarations.
*/
struct _ThresholdMap
{
char
*map_id,
*description;
size_t
width,
height;
ssize_t
divisor,
*levels;
};
/*
Static declarations.
*/
#if MAGICKCORE_ZERO_CONFIGURATION_SUPPORT
#include "MagickCore/threshold-map.h"
#else
static const char *const
BuiltinMap=
"<?xml version=\"1.0\"?>"
"<thresholds>"
" <threshold map=\"threshold\" alias=\"1x1\">"
" <description>Threshold 1x1 (non-dither)</description>"
" <levels width=\"1\" height=\"1\" divisor=\"2\">"
" 1"
" </levels>"
" </threshold>"
" <threshold map=\"checks\" alias=\"2x1\">"
" <description>Checkerboard 2x1 (dither)</description>"
" <levels width=\"2\" height=\"2\" divisor=\"3\">"
" 1 2"
" 2 1"
" </levels>"
" </threshold>"
"</thresholds>";
#endif
/*
Forward declarations.
*/
static ThresholdMap
*GetThresholdMapFile(const char *,const char *,const char *,ExceptionInfo *);
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% A d a p t i v e T h r e s h o l d I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% AdaptiveThresholdImage() selects an individual threshold for each pixel
% based on the range of intensity values in its local neighborhood. This
% allows for thresholding of an image whose global intensity histogram
% doesn't contain distinctive peaks.
%
% The format of the AdaptiveThresholdImage method is:
%
% Image *AdaptiveThresholdImage(const Image *image,const size_t width,
% const size_t height,const double bias,ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the image.
%
% o width: the width of the local neighborhood.
%
% o height: the height of the local neighborhood.
%
% o bias: the mean bias.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickExport Image *AdaptiveThresholdImage(const Image *image,
const size_t width,const size_t height,const double bias,
ExceptionInfo *exception)
{
#define AdaptiveThresholdImageTag "AdaptiveThreshold/Image"
CacheView
*image_view,
*threshold_view;
Image
*threshold_image;
MagickBooleanType
status;
MagickOffsetType
progress;
MagickSizeType
number_pixels;
ssize_t
y;
/*
Initialize threshold image attributes.
*/
assert(image != (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);
threshold_image=CloneImage(image,0,0,MagickTrue,exception);
if (threshold_image == (Image *) NULL)
return((Image *) NULL);
if ((width == 0) || (height == 0))
return(threshold_image);
status=SetImageStorageClass(threshold_image,DirectClass,exception);
if (status == MagickFalse)
{
threshold_image=DestroyImage(threshold_image);
return((Image *) NULL);
}
/*
Threshold image.
*/
status=MagickTrue;
progress=0;
number_pixels=(MagickSizeType) width*height;
image_view=AcquireVirtualCacheView(image,exception);
threshold_view=AcquireAuthenticCacheView(threshold_image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(progress,status) \
magick_number_threads(image,threshold_image,image->rows,1)
#endif
for (y=0; y < (ssize_t) image->rows; y++)
{
double
channel_bias[MaxPixelChannels],
channel_sum[MaxPixelChannels];
const Quantum
*magick_restrict p,
*magick_restrict pixels;
Quantum
*magick_restrict q;
ssize_t
i,
x;
ssize_t
center,
u,
v;
if (status == MagickFalse)
continue;
p=GetCacheViewVirtualPixels(image_view,-((ssize_t) width/2L),y-(ssize_t)
(height/2L),image->columns+width,height,exception);
q=QueueCacheViewAuthenticPixels(threshold_view,0,y,threshold_image->columns,
1,exception);
if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
{
status=MagickFalse;
continue;
}
center=(ssize_t) GetPixelChannels(image)*(image->columns+width)*(height/2L)+
GetPixelChannels(image)*(width/2);
for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
{
PixelChannel channel = GetPixelChannelChannel(image,i);
PixelTrait traits = GetPixelChannelTraits(image,channel);
PixelTrait threshold_traits=GetPixelChannelTraits(threshold_image,
channel);
if ((traits == UndefinedPixelTrait) ||
(threshold_traits == UndefinedPixelTrait))
continue;
if ((threshold_traits & CopyPixelTrait) != 0)
{
SetPixelChannel(threshold_image,channel,p[center+i],q);
continue;
}
pixels=p;
channel_bias[channel]=0.0;
channel_sum[channel]=0.0;
for (v=0; v < (ssize_t) height; v++)
{
for (u=0; u < (ssize_t) width; u++)
{
if (u == (ssize_t) (width-1))
channel_bias[channel]+=pixels[i];
channel_sum[channel]+=pixels[i];
pixels+=GetPixelChannels(image);
}
pixels+=GetPixelChannels(image)*image->columns;
}
}
for (x=0; x < (ssize_t) image->columns; x++)
{
for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
{
double
mean;
PixelChannel channel = GetPixelChannelChannel(image,i);
PixelTrait traits = GetPixelChannelTraits(image,channel);
PixelTrait threshold_traits=GetPixelChannelTraits(threshold_image,
channel);
if ((traits == UndefinedPixelTrait) ||
(threshold_traits == UndefinedPixelTrait))
continue;
if ((threshold_traits & CopyPixelTrait) != 0)
{
SetPixelChannel(threshold_image,channel,p[center+i],q);
continue;
}
channel_sum[channel]-=channel_bias[channel];
channel_bias[channel]=0.0;
pixels=p;
for (v=0; v < (ssize_t) height; v++)
{
channel_bias[channel]+=pixels[i];
pixels+=(width-1)*GetPixelChannels(image);
channel_sum[channel]+=pixels[i];
pixels+=GetPixelChannels(image)*(image->columns+1);
}
mean=(double) (channel_sum[channel]/number_pixels+bias);
SetPixelChannel(threshold_image,channel,(Quantum) ((double)
p[center+i] <= mean ? 0 : QuantumRange),q);
}
p+=GetPixelChannels(image);
q+=GetPixelChannels(threshold_image);
}
if (SyncCacheViewAuthenticPixels(threshold_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,AdaptiveThresholdImageTag,progress,
image->rows);
if (proceed == MagickFalse)
status=MagickFalse;
}
}
threshold_image->type=image->type;
threshold_view=DestroyCacheView(threshold_view);
image_view=DestroyCacheView(image_view);
if (status == MagickFalse)
threshold_image=DestroyImage(threshold_image);
return(threshold_image);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% A u t o T h r e s h o l d I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% AutoThresholdImage() automatically performs image thresholding
% dependent on which method you specify.
%
% The format of the AutoThresholdImage method is:
%
% MagickBooleanType AutoThresholdImage(Image *image,
% const AutoThresholdMethod method,ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: The image to auto-threshold.
%
% o method: choose from Kapur, OTSU, or Triangle.
%
% o exception: return any errors or warnings in this structure.
%
*/
static double KapurThreshold(const Image *image,const double *histogram,
ExceptionInfo *exception)
{
#define MaxIntensity 255
double
*black_entropy,
*cumulative_histogram,
entropy,
epsilon,
maximum_entropy,
*white_entropy;
ssize_t
i,
j;
size_t
threshold;
/*
Compute optimal threshold from the entopy of the histogram.
*/
cumulative_histogram=(double *) AcquireQuantumMemory(MaxIntensity+1UL,
sizeof(*cumulative_histogram));
black_entropy=(double *) AcquireQuantumMemory(MaxIntensity+1UL,
sizeof(*black_entropy));
white_entropy=(double *) AcquireQuantumMemory(MaxIntensity+1UL,
sizeof(*white_entropy));
if ((cumulative_histogram == (double *) NULL) ||
(black_entropy == (double *) NULL) || (white_entropy == (double *) NULL))
{
if (white_entropy != (double *) NULL)
white_entropy=(double *) RelinquishMagickMemory(white_entropy);
if (black_entropy != (double *) NULL)
black_entropy=(double *) RelinquishMagickMemory(black_entropy);
if (cumulative_histogram != (double *) NULL)
cumulative_histogram=(double *)
RelinquishMagickMemory(cumulative_histogram);
(void) ThrowMagickException(exception,GetMagickModule(),
ResourceLimitError,"MemoryAllocationFailed","`%s'",image->filename);
return(-1.0);
}
/*
Entropy for black and white parts of the histogram.
*/
cumulative_histogram[0]=histogram[0];
for (i=1; i <= MaxIntensity; i++)
cumulative_histogram[i]=cumulative_histogram[i-1]+histogram[i];
epsilon=MagickMinimumValue;
for (j=0; j <= MaxIntensity; j++)
{
/*
Black entropy.
*/
black_entropy[j]=0.0;
if (cumulative_histogram[j] > epsilon)
{
entropy=0.0;
for (i=0; i <= j; i++)
if (histogram[i] > epsilon)
entropy-=histogram[i]/cumulative_histogram[j]*
log(histogram[i]/cumulative_histogram[j]);
black_entropy[j]=entropy;
}
/*
White entropy.
*/
white_entropy[j]=0.0;
if ((1.0-cumulative_histogram[j]) > epsilon)
{
entropy=0.0;
for (i=j+1; i <= MaxIntensity; i++)
if (histogram[i] > epsilon)
entropy-=histogram[i]/(1.0-cumulative_histogram[j])*
log(histogram[i]/(1.0-cumulative_histogram[j]));
white_entropy[j]=entropy;
}
}
/*
Find histogram bin with maximum entropy.
*/
maximum_entropy=black_entropy[0]+white_entropy[0];
threshold=0;
for (j=1; j <= MaxIntensity; j++)
if ((black_entropy[j]+white_entropy[j]) > maximum_entropy)
{
maximum_entropy=black_entropy[j]+white_entropy[j];
threshold=(size_t) j;
}
/*
Free resources.
*/
white_entropy=(double *) RelinquishMagickMemory(white_entropy);
black_entropy=(double *) RelinquishMagickMemory(black_entropy);
cumulative_histogram=(double *) RelinquishMagickMemory(cumulative_histogram);
return(100.0*threshold/MaxIntensity);
}
static double OTSUThreshold(const Image *image,const double *histogram,
ExceptionInfo *exception)
{
double
max_sigma,
*myu,
*omega,
*probability,
*sigma,
threshold;
ssize_t
i;
/*
Compute optimal threshold from maximization of inter-class variance.
*/
myu=(double *) AcquireQuantumMemory(MaxIntensity+1UL,sizeof(*myu));
omega=(double *) AcquireQuantumMemory(MaxIntensity+1UL,sizeof(*omega));
probability=(double *) AcquireQuantumMemory(MaxIntensity+1UL,
sizeof(*probability));
sigma=(double *) AcquireQuantumMemory(MaxIntensity+1UL,sizeof(*sigma));
if ((myu == (double *) NULL) || (omega == (double *) NULL) ||
(probability == (double *) NULL) || (sigma == (double *) NULL))
{
if (sigma != (double *) NULL)
sigma=(double *) RelinquishMagickMemory(sigma);
if (probability != (double *) NULL)
probability=(double *) RelinquishMagickMemory(probability);
if (omega != (double *) NULL)
omega=(double *) RelinquishMagickMemory(omega);
if (myu != (double *) NULL)
myu=(double *) RelinquishMagickMemory(myu);
(void) ThrowMagickException(exception,GetMagickModule(),
ResourceLimitError,"MemoryAllocationFailed","`%s'",image->filename);
return(-1.0);
}
/*
Calculate probability density.
*/
for (i=0; i <= (ssize_t) MaxIntensity; i++)
probability[i]=histogram[i];
/*
Generate probability of graylevels and mean value for separation.
*/
omega[0]=probability[0];
myu[0]=0.0;
for (i=1; i <= (ssize_t) MaxIntensity; i++)
{
omega[i]=omega[i-1]+probability[i];
myu[i]=myu[i-1]+i*probability[i];
}
/*
Sigma maximization: inter-class variance and compute optimal threshold.
*/
threshold=0;
max_sigma=0.0;
for (i=0; i < (ssize_t) MaxIntensity; i++)
{
sigma[i]=0.0;
if ((omega[i] != 0.0) && (omega[i] != 1.0))
sigma[i]=pow(myu[MaxIntensity]*omega[i]-myu[i],2.0)/(omega[i]*(1.0-
omega[i]));
if (sigma[i] > max_sigma)
{
max_sigma=sigma[i];
threshold=(double) i;
}
}
/*
Free resources.
*/
myu=(double *) RelinquishMagickMemory(myu);
omega=(double *) RelinquishMagickMemory(omega);
probability=(double *) RelinquishMagickMemory(probability);
sigma=(double *) RelinquishMagickMemory(sigma);
return(100.0*threshold/MaxIntensity);
}
static double TriangleThreshold(const double *histogram)
{
double
a,
b,
c,
count,
distance,
inverse_ratio,
max_distance,
segment,
x1,
x2,
y1,
y2;
ssize_t
i;
ssize_t
end,
max,
start,
threshold;
/*
Compute optimal threshold with triangle algorithm.
*/
start=0; /* find start bin, first bin not zero count */
for (i=0; i <= (ssize_t) MaxIntensity; i++)
if (histogram[i] > 0.0)
{
start=i;
break;
}
end=0; /* find end bin, last bin not zero count */
for (i=(ssize_t) MaxIntensity; i >= 0; i--)
if (histogram[i] > 0.0)
{
end=i;
break;
}
max=0; /* find max bin, bin with largest count */
count=0.0;
for (i=0; i <= (ssize_t) MaxIntensity; i++)
if (histogram[i] > count)
{
max=i;
count=histogram[i];
}
/*
Compute threshold at split point.
*/
x1=(double) max;
y1=histogram[max];
x2=(double) end;
if ((max-start) >= (end-max))
x2=(double) start;
y2=0.0;
a=y1-y2;
b=x2-x1;
c=(-1.0)*(a*x1+b*y1);
inverse_ratio=1.0/sqrt(a*a+b*b+c*c);
threshold=0;
max_distance=0.0;
if (x2 == (double) start)
for (i=start; i < max; i++)
{
segment=inverse_ratio*(a*i+b*histogram[i]+c);
distance=sqrt(segment*segment);
if ((distance > max_distance) && (segment > 0.0))
{
threshold=i;
max_distance=distance;
}
}
else
for (i=end; i > max; i--)
{
segment=inverse_ratio*(a*i+b*histogram[i]+c);
distance=sqrt(segment*segment);
if ((distance > max_distance) && (segment < 0.0))
{
threshold=i;
max_distance=distance;
}
}
return(100.0*threshold/MaxIntensity);
}
MagickExport MagickBooleanType AutoThresholdImage(Image *image,
const AutoThresholdMethod method,ExceptionInfo *exception)
{
CacheView
*image_view;
char
property[MagickPathExtent];
double
gamma,
*histogram,
sum,
threshold;
MagickBooleanType
status;
ssize_t
i;
ssize_t
y;
/*
Form histogram.
*/
assert(image != (Image *) NULL);
assert(image->signature == MagickCoreSignature);
if (image->debug != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
histogram=(double *) AcquireQuantumMemory(MaxIntensity+1UL,
sizeof(*histogram));
if (histogram == (double *) NULL)
ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
image->filename);
status=MagickTrue;
(void) memset(histogram,0,(MaxIntensity+1UL)*sizeof(*histogram));
image_view=AcquireVirtualCacheView(image,exception);
for (y=0; y < (ssize_t) image->rows; y++)
{
const Quantum
*magick_restrict p;
ssize_t
x;
p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
if (p == (const Quantum *) NULL)
break;
for (x=0; x < (ssize_t) image->columns; x++)
{
double intensity = GetPixelIntensity(image,p);
histogram[ScaleQuantumToChar(ClampToQuantum(intensity))]++;
p+=GetPixelChannels(image);
}
}
image_view=DestroyCacheView(image_view);
/*
Normalize histogram.
*/
sum=0.0;
for (i=0; i <= (ssize_t) MaxIntensity; i++)
sum+=histogram[i];
gamma=PerceptibleReciprocal(sum);
for (i=0; i <= (ssize_t) MaxIntensity; i++)
histogram[i]=gamma*histogram[i];
/*
Discover threshold from histogram.
*/
switch (method)
{
case KapurThresholdMethod:
{
threshold=KapurThreshold(image,histogram,exception);
break;
}
case OTSUThresholdMethod:
default:
{
threshold=OTSUThreshold(image,histogram,exception);
break;
}
case TriangleThresholdMethod:
{
threshold=TriangleThreshold(histogram);
break;
}
}
histogram=(double *) RelinquishMagickMemory(histogram);
if (threshold < 0.0)
status=MagickFalse;
if (status == MagickFalse)
return(MagickFalse);
/*
Threshold image.
*/
(void) FormatLocaleString(property,MagickPathExtent,"%g%%",threshold);
(void) SetImageProperty(image,"auto-threshold:threshold",property,exception);
if (IsStringTrue(GetImageArtifact(image,"auto-threshold:verbose")) != MagickFalse)
(void) FormatLocaleFile(stdout,"%.*g%%\n",GetMagickPrecision(),threshold);
return(BilevelImage(image,QuantumRange*threshold/100.0,exception));
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% B i l e v e l I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% BilevelImage() changes the value of individual pixels based on the
% intensity of each pixel channel. The result is a high-contrast image.
%
% More precisely each channel value of the image is 'thresholded' so that if
% it is equal to or less than the given value it is set to zero, while any
% value greater than that give is set to it maximum or QuantumRange.
%
% This function is what is used to implement the "-threshold" operator for
% the command line API.
%
% If the default channel setting is given the image is thresholded using just
% the gray 'intensity' of the image, rather than the individual channels.
%
% The format of the BilevelImage method is:
%
% MagickBooleanType BilevelImage(Image *image,const double threshold,
% ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the image.
%
% o threshold: define the threshold values.
%
% o exception: return any errors or warnings in this structure.
%
% Aside: You can get the same results as operator using LevelImages()
% with the 'threshold' value for both the black_point and the white_point.
%
*/
MagickExport MagickBooleanType BilevelImage(Image *image,const double threshold,
ExceptionInfo *exception)
{
#define ThresholdImageTag "Threshold/Image"
CacheView
*image_view;
MagickBooleanType
status;
MagickOffsetType
progress;
ssize_t
y;
assert(image != (Image *) NULL);
assert(image->signature == MagickCoreSignature);
if (image->debug != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
if (SetImageStorageClass(image,DirectClass,exception) == MagickFalse)
return(MagickFalse);
if (IsGrayColorspace(image->colorspace) == MagickFalse)
(void) SetImageColorspace(image,sRGBColorspace,exception);
/*
Bilevel threshold image.
*/
status=MagickTrue;
progress=0;
image_view=AcquireAuthenticCacheView(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(progress,status) \
magick_number_threads(image,image,image->rows,1)
#endif
for (y=0; y < (ssize_t) image->rows; y++)
{
ssize_t
x;
Quantum
*magick_restrict q;
if (status == MagickFalse)
continue;
q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
if (q == (Quantum *) NULL)
{
status=MagickFalse;
continue;
}
for (x=0; x < (ssize_t) image->columns; x++)
{
double
pixel;
ssize_t
i;
pixel=GetPixelIntensity(image,q);
for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
{
PixelChannel channel = GetPixelChannelChannel(image,i);
PixelTrait traits = GetPixelChannelTraits(image,channel);
if ((traits & UpdatePixelTrait) == 0)
continue;
if (image->channel_mask != DefaultChannels)
pixel=(double) q[i];
q[i]=(Quantum) (pixel <= threshold ? 0 : QuantumRange);
}
q+=GetPixelChannels(image);
}
if (SyncCacheViewAuthenticPixels(image_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,ThresholdImageTag,progress++,
image->rows);
if (proceed == MagickFalse)
status=MagickFalse;
}
}
image_view=DestroyCacheView(image_view);
return(status);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% B l a c k T h r e s h o l d I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% BlackThresholdImage() is like ThresholdImage() but forces all pixels below
% the threshold into black while leaving all pixels at or above the threshold
% unchanged.
%
% The format of the BlackThresholdImage method is:
%
% MagickBooleanType BlackThresholdImage(Image *image,
% const char *threshold,ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the image.
%
% o threshold: define the threshold value.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickExport MagickBooleanType BlackThresholdImage(Image *image,
const char *thresholds,ExceptionInfo *exception)
{
#define ThresholdImageTag "Threshold/Image"
CacheView
*image_view;
GeometryInfo
geometry_info;
MagickBooleanType
status;
MagickOffsetType
progress;
PixelInfo
threshold;
MagickStatusType
flags;
ssize_t
y;
assert(image != (Image *) NULL);
assert(image->signature == MagickCoreSignature);
if (image->debug != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
if (thresholds == (const char *) NULL)
return(MagickTrue);
if (SetImageStorageClass(image,DirectClass,exception) == MagickFalse)
return(MagickFalse);
if (IsGrayColorspace(image->colorspace) != MagickFalse)
(void) SetImageColorspace(image,sRGBColorspace,exception);
GetPixelInfo(image,&threshold);
flags=ParseGeometry(thresholds,&geometry_info);
threshold.red=geometry_info.rho;
threshold.green=geometry_info.rho;
threshold.blue=geometry_info.rho;
threshold.black=geometry_info.rho;
threshold.alpha=100.0;
if ((flags & SigmaValue) != 0)
threshold.green=geometry_info.sigma;
if ((flags & XiValue) != 0)
threshold.blue=geometry_info.xi;
if ((flags & PsiValue) != 0)
threshold.alpha=geometry_info.psi;
if (threshold.colorspace == CMYKColorspace)
{
if ((flags & PsiValue) != 0)
threshold.black=geometry_info.psi;
if ((flags & ChiValue) != 0)
threshold.alpha=geometry_info.chi;
}
if ((flags & PercentValue) != 0)
{
threshold.red*=(MagickRealType) (QuantumRange/100.0);
threshold.green*=(MagickRealType) (QuantumRange/100.0);
threshold.blue*=(MagickRealType) (QuantumRange/100.0);
threshold.black*=(MagickRealType) (QuantumRange/100.0);
threshold.alpha*=(MagickRealType) (QuantumRange/100.0);
}
/*
White threshold image.
*/
status=MagickTrue;
progress=0;
image_view=AcquireAuthenticCacheView(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(progress,status) \
magick_number_threads(image,image,image->rows,1)
#endif
for (y=0; y < (ssize_t) image->rows; y++)
{
ssize_t
x;
Quantum
*magick_restrict q;
if (status == MagickFalse)
continue;
q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
if (q == (Quantum *) NULL)
{
status=MagickFalse;
continue;
}
for (x=0; x < (ssize_t) image->columns; x++)
{
double
pixel;
ssize_t
i;
pixel=GetPixelIntensity(image,q);
for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
{
PixelChannel channel = GetPixelChannelChannel(image,i);
PixelTrait traits = GetPixelChannelTraits(image,channel);
if ((traits & UpdatePixelTrait) == 0)
continue;
if (image->channel_mask != DefaultChannels)
pixel=(double) q[i];
if (pixel < GetPixelInfoChannel(&threshold,channel))
q[i]=(Quantum) 0;
}
q+=GetPixelChannels(image);
}
if (SyncCacheViewAuthenticPixels(image_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,ThresholdImageTag,progress,
image->rows);
if (proceed == MagickFalse)
status=MagickFalse;
}
}
image_view=DestroyCacheView(image_view);
return(status);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% C l a m p I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ClampImage() set each pixel whose value is below zero to zero and any the
% pixel whose value is above the quantum range to the quantum range (e.g.
% 65535) otherwise the pixel value remains unchanged.
%
% The format of the ClampImage method is:
%
% MagickBooleanType ClampImage(Image *image,ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the image.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickExport MagickBooleanType ClampImage(Image *image,ExceptionInfo *exception)
{
#define ClampImageTag "Clamp/Image"
CacheView
*image_view;
MagickBooleanType
status;
MagickOffsetType
progress;
ssize_t
y;
assert(image != (Image *) NULL);
assert(image->signature == MagickCoreSignature);
if (image->debug != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
if (image->storage_class == PseudoClass)
{
ssize_t
i;
PixelInfo
*magick_restrict q;
q=image->colormap;
for (i=0; i < (ssize_t) image->colors; i++)
{
q->red=(double) ClampPixel(q->red);
q->green=(double) ClampPixel(q->green);
q->blue=(double) ClampPixel(q->blue);
q->alpha=(double) ClampPixel(q->alpha);
q++;
}
return(SyncImage(image,exception));
}
/*
Clamp image.
*/
status=MagickTrue;
progress=0;
image_view=AcquireAuthenticCacheView(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(progress,status) \
magick_number_threads(image,image,image->rows,1)
#endif
for (y=0; y < (ssize_t) image->rows; y++)
{
ssize_t
x;
Quantum
*magick_restrict q;
if (status == MagickFalse)
continue;
q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
if (q == (Quantum *) NULL)
{
status=MagickFalse;
continue;
}
for (x=0; x < (ssize_t) image->columns; x++)
{
ssize_t
i;
for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
{
PixelChannel channel = GetPixelChannelChannel(image,i);
PixelTrait traits = GetPixelChannelTraits(image,channel);
if ((traits & UpdatePixelTrait) == 0)
continue;
q[i]=ClampPixel((MagickRealType) q[i]);
}
q+=GetPixelChannels(image);
}
if (SyncCacheViewAuthenticPixels(image_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,ClampImageTag,progress,image->rows);
if (proceed == MagickFalse)
status=MagickFalse;
}
}
image_view=DestroyCacheView(image_view);
return(status);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% C o l o r T h r e s h o l d I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ColorThresholdImage() forces all pixels in the color range to white
% otherwise black.
%
% The format of the ColorThresholdImage method is:
%
% MagickBooleanType ColorThresholdImage(Image *image,
% const PixelInfo *start_color,const PixelInfo *stop_color,
% ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the image.
%
% o start_color, stop_color: define the start and stop color range. Any
% pixel within the range returns white otherwise black.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickExport MagickBooleanType ColorThresholdImage(Image *image,
const PixelInfo *start_color,const PixelInfo *stop_color,
ExceptionInfo *exception)
{
#define ThresholdImageTag "Threshold/Image"
CacheView
*image_view;
const char
*artifact;
IlluminantType
illuminant = D65Illuminant;
MagickBooleanType
status;
MagickOffsetType
progress;
PixelInfo
start,
stop;
ssize_t
y;
/*
Color threshold image.
*/
assert(image != (Image *) NULL);
assert(image->signature == MagickCoreSignature);
if (image->debug != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
status=AcquireImageColormap(image,2,exception);
if (status == MagickFalse)
return(status);
artifact=GetImageArtifact(image,"color:illuminant");
if (artifact != (const char *) NULL)
{
illuminant=(IlluminantType) ParseCommandOption(MagickIlluminantOptions,
MagickFalse,artifact);
if ((ssize_t) illuminant < 0)
illuminant=UndefinedIlluminant;
}
start=(*start_color);
stop=(*stop_color);
switch (image->colorspace)
{
case HCLColorspace:
{
ConvertRGBToHCL(start_color->red,start_color->green,start_color->blue,
&start.red,&start.green,&start.blue);
ConvertRGBToHCL(stop_color->red,stop_color->green,stop_color->blue,
&stop.red,&stop.green,&stop.blue);
break;
}
case HSBColorspace:
{
ConvertRGBToHSB(start_color->red,start_color->green,start_color->blue,
&start.red,&start.green,&start.blue);
ConvertRGBToHSB(stop_color->red,stop_color->green,stop_color->blue,
&stop.red,&stop.green,&stop.blue);
break;
}
case HSLColorspace:
{
ConvertRGBToHSL(start_color->red,start_color->green,start_color->blue,
&start.red,&start.green,&start.blue);
ConvertRGBToHSL(stop_color->red,stop_color->green,stop_color->blue,
&stop.red,&stop.green,&stop.blue);
break;
}
case HSVColorspace:
{
ConvertRGBToHSV(start_color->red,start_color->green,start_color->blue,
&start.red,&start.green,&start.blue);
ConvertRGBToHSV(stop_color->red,stop_color->green,stop_color->blue,
&stop.red,&stop.green,&stop.blue);
break;
}
case HWBColorspace:
{
ConvertRGBToHWB(start_color->red,start_color->green,start_color->blue,
&start.red,&start.green,&start.blue);
ConvertRGBToHWB(stop_color->red,stop_color->green,stop_color->blue,
&stop.red,&stop.green,&stop.blue);
break;
}
case LabColorspace:
{
ConvertRGBToLab(start_color->red,start_color->green,start_color->blue,
illuminant,&start.red,&start.green,&start.blue);
ConvertRGBToLab(stop_color->red,stop_color->green,stop_color->blue,
illuminant,&stop.red,&stop.green,&stop.blue);
break;
}
default:
{
start.red*=QuantumScale;
start.green*=QuantumScale;
start.blue*=QuantumScale;
stop.red*=QuantumScale;
stop.green*=QuantumScale;
stop.blue*=QuantumScale;
break;
}
}
start.red*=QuantumRange;
start.green*=QuantumRange;
start.blue*=QuantumRange;
stop.red*=QuantumRange;
stop.green*=QuantumRange;
stop.blue*=QuantumRange;
progress=0;
image_view=AcquireAuthenticCacheView(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(progress,status) \
magick_number_threads(image,image,image->rows,1)
#endif
for (y=0; y < (ssize_t) image->rows; y++)
{
ssize_t
x;
Quantum
*magick_restrict q;
if (status == MagickFalse)
continue;
q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
if (q == (Quantum *) NULL)
{
status=MagickFalse;
continue;
}
for (x=0; x < (ssize_t) image->columns; x++)
{
MagickBooleanType
foreground = MagickTrue;
ssize_t
i;
for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
{
PixelChannel channel = GetPixelChannelChannel(image,i);
PixelTrait traits = GetPixelChannelTraits(image,channel);
if ((traits & UpdatePixelTrait) == 0)
continue;
if ((q[i] < GetPixelInfoChannel(&start,channel)) ||
(q[i] > GetPixelInfoChannel(&stop,channel)))
foreground=MagickFalse;
}
SetPixelIndex(image,(Quantum) (foreground != MagickFalse ? 1 : 0),q);
q+=GetPixelChannels(image);
}
if (SyncCacheViewAuthenticPixels(image_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,ThresholdImageTag,progress,
image->rows);
if (proceed == MagickFalse)
status=MagickFalse;
}
}
image_view=DestroyCacheView(image_view);
image->colorspace=sRGBColorspace;
return(SyncImage(image,exception));
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% D e s t r o y T h r e s h o l d M a p %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% DestroyThresholdMap() de-allocate the given ThresholdMap
%
% The format of the ListThresholdMaps method is:
%
% ThresholdMap *DestroyThresholdMap(Threshold *map)
%
% A description of each parameter follows.
%
% o map: Pointer to the Threshold map to destroy
%
*/
MagickExport ThresholdMap *DestroyThresholdMap(ThresholdMap *map)
{
assert(map != (ThresholdMap *) NULL);
if (map->map_id != (char *) NULL)
map->map_id=DestroyString(map->map_id);
if (map->description != (char *) NULL)
map->description=DestroyString(map->description);
if (map->levels != (ssize_t *) NULL)
map->levels=(ssize_t *) RelinquishMagickMemory(map->levels);
map=(ThresholdMap *) RelinquishMagickMemory(map);
return(map);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% G e t T h r e s h o l d M a p %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% GetThresholdMap() loads and searches one or more threshold map files for the
% map matching the given name or alias.
%
% The format of the GetThresholdMap method is:
%
% ThresholdMap *GetThresholdMap(const char *map_id,
% ExceptionInfo *exception)
%
% A description of each parameter follows.
%
% o map_id: ID of the map to look for.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickExport ThresholdMap *GetThresholdMap(const char *map_id,
ExceptionInfo *exception)
{
ThresholdMap
*map;
map=GetThresholdMapFile(BuiltinMap,"built-in",map_id,exception);
if (map != (ThresholdMap *) NULL)
return(map);
#if !MAGICKCORE_ZERO_CONFIGURATION_SUPPORT
{
const StringInfo
*option;
LinkedListInfo
*options;
options=GetConfigureOptions(ThresholdsFilename,exception);
option=(const StringInfo *) GetNextValueInLinkedList(options);
while (option != (const StringInfo *) NULL)
{
map=GetThresholdMapFile((const char *) GetStringInfoDatum(option),
GetStringInfoPath(option),map_id,exception);
if (map != (ThresholdMap *) NULL)
break;
option=(const StringInfo *) GetNextValueInLinkedList(options);
}
options=DestroyConfigureOptions(options);
}
#endif
return(map);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
+ G e t T h r e s h o l d M a p F i l e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% GetThresholdMapFile() look for a given threshold map name or alias in the
% given XML file data, and return the allocated the map when found.
%
% The format of the ListThresholdMaps method is:
%
% ThresholdMap *GetThresholdMap(const char *xml,const char *filename,
% const char *map_id,ExceptionInfo *exception)
%
% A description of each parameter follows.
%
% o xml: The threshold map list in XML format.
%
% o filename: The threshold map XML filename.
%
% o map_id: ID of the map to look for in XML list.
%
% o exception: return any errors or warnings in this structure.
%
*/
static ThresholdMap *GetThresholdMapFile(const char *xml,const char *filename,
const char *map_id,ExceptionInfo *exception)
{
char
*p;
const char
*attribute,
*content;
double
value;
ssize_t
i;
ThresholdMap
*map;
XMLTreeInfo
*description,
*levels,
*threshold,
*thresholds;
(void) LogMagickEvent(ConfigureEvent,GetMagickModule(),
"Loading threshold map file \"%s\" ...",filename);
map=(ThresholdMap *) NULL;
thresholds=NewXMLTree(xml,exception);
if (thresholds == (XMLTreeInfo *) NULL)
return(map);
for (threshold=GetXMLTreeChild(thresholds,"threshold");
threshold != (XMLTreeInfo *) NULL;
threshold=GetNextXMLTreeTag(threshold))
{
attribute=GetXMLTreeAttribute(threshold,"map");
if ((attribute != (char *) NULL) && (LocaleCompare(map_id,attribute) == 0))
break;
attribute=GetXMLTreeAttribute(threshold,"alias");
if ((attribute != (char *) NULL) && (LocaleCompare(map_id,attribute) == 0))
break;
}
if (threshold == (XMLTreeInfo *) NULL)
{
thresholds=DestroyXMLTree(thresholds);
return(map);
}
description=GetXMLTreeChild(threshold,"description");
if (description == (XMLTreeInfo *) NULL)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlMissingElement", "<description>, map \"%s\"",map_id);
thresholds=DestroyXMLTree(thresholds);
return(map);
}
levels=GetXMLTreeChild(threshold,"levels");
if (levels == (XMLTreeInfo *) NULL)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlMissingElement", "<levels>, map \"%s\"", map_id);
thresholds=DestroyXMLTree(thresholds);
return(map);
}
map=(ThresholdMap *) AcquireCriticalMemory(sizeof(*map));
map->map_id=(char *) NULL;
map->description=(char *) NULL;
map->levels=(ssize_t *) NULL;
attribute=GetXMLTreeAttribute(threshold,"map");
if (attribute != (char *) NULL)
map->map_id=ConstantString(attribute);
content=GetXMLTreeContent(description);
if (content != (char *) NULL)
map->description=ConstantString(content);
attribute=GetXMLTreeAttribute(levels,"width");
if (attribute == (char *) NULL)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlMissingAttribute", "<levels width>, map \"%s\"",map_id);
thresholds=DestroyXMLTree(thresholds);
map=DestroyThresholdMap(map);
return(map);
}
map->width=StringToUnsignedLong(attribute);
if (map->width == 0)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlInvalidAttribute", "<levels width>, map \"%s\"",map_id);
thresholds=DestroyXMLTree(thresholds);
map=DestroyThresholdMap(map);
return(map);
}
attribute=GetXMLTreeAttribute(levels,"height");
if (attribute == (char *) NULL)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlMissingAttribute", "<levels height>, map \"%s\"",map_id);
thresholds=DestroyXMLTree(thresholds);
map=DestroyThresholdMap(map);
return(map);
}
map->height=StringToUnsignedLong(attribute);
if (map->height == 0)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlInvalidAttribute", "<levels height>, map \"%s\"",map_id);
thresholds=DestroyXMLTree(thresholds);
map=DestroyThresholdMap(map);
return(map);
}
attribute=GetXMLTreeAttribute(levels,"divisor");
if (attribute == (char *) NULL)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlMissingAttribute", "<levels divisor>, map \"%s\"",map_id);
thresholds=DestroyXMLTree(thresholds);
map=DestroyThresholdMap(map);
return(map);
}
map->divisor=(ssize_t) StringToLong(attribute);
if (map->divisor < 2)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlInvalidAttribute", "<levels divisor>, map \"%s\"",map_id);
thresholds=DestroyXMLTree(thresholds);
map=DestroyThresholdMap(map);
return(map);
}
content=GetXMLTreeContent(levels);
if (content == (char *) NULL)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlMissingContent", "<levels>, map \"%s\"",map_id);
thresholds=DestroyXMLTree(thresholds);
map=DestroyThresholdMap(map);
return(map);
}
map->levels=(ssize_t *) AcquireQuantumMemory((size_t) map->width,map->height*
sizeof(*map->levels));
if (map->levels == (ssize_t *) NULL)
ThrowFatalException(ResourceLimitFatalError,"UnableToAcquireThresholdMap");
for (i=0; i < (ssize_t) (map->width*map->height); i++)
{
map->levels[i]=(ssize_t) strtol(content,&p,10);
if (p == content)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlInvalidContent", "<level> too few values, map \"%s\"",map_id);
thresholds=DestroyXMLTree(thresholds);
map=DestroyThresholdMap(map);
return(map);
}
if ((map->levels[i] < 0) || (map->levels[i] > map->divisor))
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlInvalidContent", "<level> %.20g out of range, map \"%s\"",
(double) map->levels[i],map_id);
thresholds=DestroyXMLTree(thresholds);
map=DestroyThresholdMap(map);
return(map);
}
content=p;
}
value=(double) strtol(content,&p,10);
(void) value;
if (p != content)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlInvalidContent", "<level> too many values, map \"%s\"",map_id);
thresholds=DestroyXMLTree(thresholds);
map=DestroyThresholdMap(map);
return(map);
}
thresholds=DestroyXMLTree(thresholds);
return(map);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
+ L i s t T h r e s h o l d M a p F i l e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ListThresholdMapFile() lists the threshold maps and their descriptions
% in the given XML file data.
%
% The format of the ListThresholdMaps method is:
%
% MagickBooleanType ListThresholdMaps(FILE *file,const char*xml,
% const char *filename,ExceptionInfo *exception)
%
% A description of each parameter follows.
%
% o file: An pointer to the output FILE.
%
% o xml: The threshold map list in XML format.
%
% o filename: The threshold map XML filename.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickBooleanType ListThresholdMapFile(FILE *file,const char *xml,
const char *filename,ExceptionInfo *exception)
{
const char
*alias,
*content,
*map;
XMLTreeInfo
*description,
*threshold,
*thresholds;
assert( xml != (char *) NULL );
assert( file != (FILE *) NULL );
(void) LogMagickEvent(ConfigureEvent,GetMagickModule(),
"Loading threshold map file \"%s\" ...",filename);
thresholds=NewXMLTree(xml,exception);
if ( thresholds == (XMLTreeInfo *) NULL )
return(MagickFalse);
(void) FormatLocaleFile(file,"%-16s %-12s %s\n","Map","Alias","Description");
(void) FormatLocaleFile(file,
"----------------------------------------------------\n");
threshold=GetXMLTreeChild(thresholds,"threshold");
for ( ; threshold != (XMLTreeInfo *) NULL;
threshold=GetNextXMLTreeTag(threshold))
{
map=GetXMLTreeAttribute(threshold,"map");
if (map == (char *) NULL)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlMissingAttribute", "<map>");
thresholds=DestroyXMLTree(thresholds);
return(MagickFalse);
}
alias=GetXMLTreeAttribute(threshold,"alias");
description=GetXMLTreeChild(threshold,"description");
if (description == (XMLTreeInfo *) NULL)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlMissingElement", "<description>, map \"%s\"",map);
thresholds=DestroyXMLTree(thresholds);
return(MagickFalse);
}
content=GetXMLTreeContent(description);
if (content == (char *) NULL)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"XmlMissingContent", "<description>, map \"%s\"", map);
thresholds=DestroyXMLTree(thresholds);
return(MagickFalse);
}
(void) FormatLocaleFile(file,"%-16s %-12s %s\n",map,alias ? alias : "",
content);
}
thresholds=DestroyXMLTree(thresholds);
return(MagickTrue);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% L i s t T h r e s h o l d M a p s %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ListThresholdMaps() lists the threshold maps and their descriptions
% as defined by "threshold.xml" to a file.
%
% The format of the ListThresholdMaps method is:
%
% MagickBooleanType ListThresholdMaps(FILE *file,ExceptionInfo *exception)
%
% A description of each parameter follows.
%
% o file: An pointer to the output FILE.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickExport MagickBooleanType ListThresholdMaps(FILE *file,
ExceptionInfo *exception)
{
const StringInfo
*option;
LinkedListInfo
*options;
MagickStatusType
status;
status=MagickTrue;
if (file == (FILE *) NULL)
file=stdout;
options=GetConfigureOptions(ThresholdsFilename,exception);
(void) FormatLocaleFile(file,
"\n Threshold Maps for Ordered Dither Operations\n");
option=(const StringInfo *) GetNextValueInLinkedList(options);
while (option != (const StringInfo *) NULL)
{
(void) FormatLocaleFile(file,"\nPath: %s\n\n",GetStringInfoPath(option));
status&=ListThresholdMapFile(file,(const char *) GetStringInfoDatum(option),
GetStringInfoPath(option),exception);
option=(const StringInfo *) GetNextValueInLinkedList(options);
}
options=DestroyConfigureOptions(options);
return(status != 0 ? MagickTrue : MagickFalse);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% O r d e r e d D i t h e r I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% OrderedDitherImage() will perform a ordered dither based on a number
% of pre-defined dithering threshold maps, but over multiple intensity
% levels, which can be different for different channels, according to the
% input argument.
%
% The format of the OrderedDitherImage method is:
%
% MagickBooleanType OrderedDitherImage(Image *image,
% const char *threshold_map,ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the image.
%
% o threshold_map: A string containing the name of the threshold dither
% map to use, followed by zero or more numbers representing the number
% of color levels to dither between.
%
% Any level number less than 2 will be equivalent to 2, and means only
% binary dithering will be applied to each color channel.
%
% No numbers also means a 2 level (bitmap) dither will be applied to all
% channels, while a single number is the number of levels applied to each
% channel in sequence. More numbers will be applied in turn to each of
% the color channels.
%
% For example: "o3x3,6" will generate a 6 level posterization of the
% image with an ordered 3x3 diffused pixel dither being applied between
% each level. While checker,8,8,4 will produce a 332 colormaped image
% with only a single checkerboard hash pattern (50% grey) between each
% color level, to basically double the number of color levels with
% a bare minimim of dithering.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickExport MagickBooleanType OrderedDitherImage(Image *image,
const char *threshold_map,ExceptionInfo *exception)
{
#define DitherImageTag "Dither/Image"
CacheView
*image_view;
char
token[MagickPathExtent];
const char
*p;
double
levels[CompositePixelChannel];
MagickBooleanType
status;
MagickOffsetType
progress;
ssize_t
i;
ssize_t
y;
ThresholdMap
*map;
assert(image != (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);
if (threshold_map == (const char *) NULL)
return(MagickTrue);
p=(char *) threshold_map;
while (((isspace((int) ((unsigned char) *p)) != 0) || (*p == ',')) &&
(*p != '\0'))
p++;
threshold_map=p;
while (((isspace((int) ((unsigned char) *p)) == 0) && (*p != ',')) &&
(*p != '\0'))
{
if ((p-threshold_map) >= (MagickPathExtent-1))
break;
token[p-threshold_map]=(*p);
p++;
}
token[p-threshold_map]='\0';
map=GetThresholdMap(token,exception);
if (map == (ThresholdMap *) NULL)
{
(void) ThrowMagickException(exception,GetMagickModule(),OptionError,
"InvalidArgument","%s : '%s'","ordered-dither",threshold_map);
return(MagickFalse);
}
for (i=0; i < MaxPixelChannels; i++)
levels[i]=2.0;
p=strchr((char *) threshold_map,',');
if ((p != (char *) NULL) && (isdigit((int) ((unsigned char) *(++p))) != 0))
{
(void) GetNextToken(p,&p,MagickPathExtent,token);
for (i=0; (i < MaxPixelChannels); i++)
levels[i]=StringToDouble(token,(char **) NULL);
for (i=0; (*p != '\0') && (i < MaxPixelChannels); i++)
{
(void) GetNextToken(p,&p,MagickPathExtent,token);
if (*token == ',')
(void) GetNextToken(p,&p,MagickPathExtent,token);
levels[i]=StringToDouble(token,(char **) NULL);
}
}
for (i=0; i < MaxPixelChannels; i++)
if (fabs(levels[i]) >= 1)
levels[i]-=1.0;
if (SetImageStorageClass(image,DirectClass,exception) == MagickFalse)
return(MagickFalse);
status=MagickTrue;
progress=0;
image_view=AcquireAuthenticCacheView(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(progress,status) \
magick_number_threads(image,image,image->rows,1)
#endif
for (y=0; y < (ssize_t) image->rows; y++)
{
ssize_t
x;
Quantum
*magick_restrict q;
if (status == MagickFalse)
continue;
q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
if (q == (Quantum *) NULL)
{
status=MagickFalse;
continue;
}
for (x=0; x < (ssize_t) image->columns; x++)
{
ssize_t
i;
ssize_t
n;
n=0;
for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
{
ssize_t
level,
threshold;
PixelChannel channel = GetPixelChannelChannel(image,i);
PixelTrait traits = GetPixelChannelTraits(image,channel);
if ((traits & UpdatePixelTrait) == 0)
continue;
if (fabs(levels[n]) < MagickEpsilon)
{
n++;
continue;
}
threshold=(ssize_t) (QuantumScale*q[i]*(levels[n]*(map->divisor-1)+1));
level=threshold/(map->divisor-1);
threshold-=level*(map->divisor-1);
q[i]=ClampToQuantum((double) (level+(threshold >=
map->levels[(x % map->width)+map->width*(y % map->height)]))*
QuantumRange/levels[n]);
n++;
}
q+=GetPixelChannels(image);
}
if (SyncCacheViewAuthenticPixels(image_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,DitherImageTag,progress,image->rows);
if (proceed == MagickFalse)
status=MagickFalse;
}
}
image_view=DestroyCacheView(image_view);
map=DestroyThresholdMap(map);
return(MagickTrue);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% P e r c e p t i b l e I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% PerceptibleImage() set each pixel whose value is less than |epsilon| to
% epsilon or -epsilon (whichever is closer) otherwise the pixel value remains
% unchanged.
%
% The format of the PerceptibleImage method is:
%
% MagickBooleanType PerceptibleImage(Image *image,const double epsilon,
% ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the image.
%
% o epsilon: the epsilon threshold (e.g. 1.0e-9).
%
% o exception: return any errors or warnings in this structure.
%
*/
static inline Quantum PerceptibleThreshold(const Quantum quantum,
const double epsilon)
{
double
sign;
sign=(double) quantum < 0.0 ? -1.0 : 1.0;
if ((sign*quantum) >= epsilon)
return(quantum);
return((Quantum) (sign*epsilon));
}
MagickExport MagickBooleanType PerceptibleImage(Image *image,
const double epsilon,ExceptionInfo *exception)
{
#define PerceptibleImageTag "Perceptible/Image"
CacheView
*image_view;
MagickBooleanType
status;
MagickOffsetType
progress;
ssize_t
y;
assert(image != (Image *) NULL);
assert(image->signature == MagickCoreSignature);
if (image->debug != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
if (image->storage_class == PseudoClass)
{
ssize_t
i;
PixelInfo
*magick_restrict q;
q=image->colormap;
for (i=0; i < (ssize_t) image->colors; i++)
{
q->red=(double) PerceptibleThreshold(ClampToQuantum(q->red),
epsilon);
q->green=(double) PerceptibleThreshold(ClampToQuantum(q->green),
epsilon);
q->blue=(double) PerceptibleThreshold(ClampToQuantum(q->blue),
epsilon);
q->alpha=(double) PerceptibleThreshold(ClampToQuantum(q->alpha),
epsilon);
q++;
}
return(SyncImage(image,exception));
}
/*
Perceptible image.
*/
status=MagickTrue;
progress=0;
image_view=AcquireAuthenticCacheView(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(progress,status) \
magick_number_threads(image,image,image->rows,1)
#endif
for (y=0; y < (ssize_t) image->rows; y++)
{
ssize_t
x;
Quantum
*magick_restrict q;
if (status == MagickFalse)
continue;
q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
if (q == (Quantum *) NULL)
{
status=MagickFalse;
continue;
}
for (x=0; x < (ssize_t) image->columns; x++)
{
ssize_t
i;
for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
{
PixelChannel channel = GetPixelChannelChannel(image,i);
PixelTrait traits = GetPixelChannelTraits(image,channel);
if (traits == UndefinedPixelTrait)
continue;
q[i]=PerceptibleThreshold(q[i],epsilon);
}
q+=GetPixelChannels(image);
}
if (SyncCacheViewAuthenticPixels(image_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,PerceptibleImageTag,progress,
image->rows);
if (proceed == MagickFalse)
status=MagickFalse;
}
}
image_view=DestroyCacheView(image_view);
return(status);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R a n d o m T h r e s h o l d I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% RandomThresholdImage() changes the value of individual pixels based on the
% intensity of each pixel compared to a random threshold. The result is a
% low-contrast, two color image.
%
% The format of the RandomThresholdImage method is:
%
% MagickBooleanType RandomThresholdImage(Image *image,
% const char *thresholds,ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the image.
%
% o low,high: Specify the high and low thresholds. These values range from
% 0 to QuantumRange.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickExport MagickBooleanType RandomThresholdImage(Image *image,
const double min_threshold, const double max_threshold,ExceptionInfo *exception)
{
#define ThresholdImageTag "Threshold/Image"
CacheView
*image_view;
MagickBooleanType
status;
MagickOffsetType
progress;
PixelInfo
threshold;
RandomInfo
**magick_restrict random_info;
ssize_t
y;
#if defined(MAGICKCORE_OPENMP_SUPPORT)
unsigned long
key;
#endif
assert(image != (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);
if (SetImageStorageClass(image,DirectClass,exception) == MagickFalse)
return(MagickFalse);
GetPixelInfo(image,&threshold);
/*
Random threshold image.
*/
status=MagickTrue;
progress=0;
random_info=AcquireRandomInfoThreadSet();
image_view=AcquireAuthenticCacheView(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
key=GetRandomSecretKey(random_info[0]);
#pragma omp parallel for schedule(static) shared(progress,status) \
magick_number_threads(image,image,image->rows,key == ~0UL)
#endif
for (y=0; y < (ssize_t) image->rows; y++)
{
const int
id = GetOpenMPThreadId();
Quantum
*magick_restrict q;
ssize_t
x;
if (status == MagickFalse)
continue;
q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
if (q == (Quantum *) NULL)
{
status=MagickFalse;
continue;
}
for (x=0; x < (ssize_t) image->columns; x++)
{
ssize_t
i;
for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
{
double
threshold;
PixelChannel channel = GetPixelChannelChannel(image,i);
PixelTrait traits = GetPixelChannelTraits(image,channel);
if ((traits & UpdatePixelTrait) == 0)
continue;
if ((double) q[i] < min_threshold)
threshold=min_threshold;
else
if ((double) q[i] > max_threshold)
threshold=max_threshold;
else
threshold=(double) (QuantumRange*
GetPseudoRandomValue(random_info[id]));
q[i]=(double) q[i] <= threshold ? 0 : QuantumRange;
}
q+=GetPixelChannels(image);
}
if (SyncCacheViewAuthenticPixels(image_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,ThresholdImageTag,progress,
image->rows);
if (proceed == MagickFalse)
status=MagickFalse;
}
}
image_view=DestroyCacheView(image_view);
random_info=DestroyRandomInfoThreadSet(random_info);
return(status);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R a n g e T h r e s h o l d I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% RangeThresholdImage() applies soft and hard thresholding.
%
% The format of the RangeThresholdImage method is:
%
% MagickBooleanType RangeThresholdImage(Image *image,
% const double low_black,const double low_white,const double high_white,
% const double high_black,ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the image.
%
% o low_black: Define the minimum black threshold value.
%
% o low_white: Define the minimum white threshold value.
%
% o high_white: Define the maximum white threshold value.
%
% o high_black: Define the maximum black threshold value.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickExport MagickBooleanType RangeThresholdImage(Image *image,
const double low_black,const double low_white,const double high_white,
const double high_black,ExceptionInfo *exception)
{
#define ThresholdImageTag "Threshold/Image"
CacheView
*image_view;
MagickBooleanType
status;
MagickOffsetType
progress;
ssize_t
y;
assert(image != (Image *) NULL);
assert(image->signature == MagickCoreSignature);
if (image->debug != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
if (SetImageStorageClass(image,DirectClass,exception) == MagickFalse)
return(MagickFalse);
if (IsGrayColorspace(image->colorspace) != MagickFalse)
(void) TransformImageColorspace(image,sRGBColorspace,exception);
/*
Range threshold image.
*/
status=MagickTrue;
progress=0;
image_view=AcquireAuthenticCacheView(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(progress,status) \
magick_number_threads(image,image,image->rows,1)
#endif
for (y=0; y < (ssize_t) image->rows; y++)
{
ssize_t
x;
Quantum
*magick_restrict q;
if (status == MagickFalse)
continue;
q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
if (q == (Quantum *) NULL)
{
status=MagickFalse;
continue;
}
for (x=0; x < (ssize_t) image->columns; x++)
{
double
pixel;
ssize_t
i;
pixel=GetPixelIntensity(image,q);
for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
{
PixelChannel channel = GetPixelChannelChannel(image,i);
PixelTrait traits = GetPixelChannelTraits(image,channel);
if ((traits & UpdatePixelTrait) == 0)
continue;
if (image->channel_mask != DefaultChannels)
pixel=(double) q[i];
if (pixel < low_black)
q[i]=(Quantum) 0;
else
if ((pixel >= low_black) && (pixel < low_white))
q[i]=ClampToQuantum(QuantumRange*
PerceptibleReciprocal(low_white-low_black)*(pixel-low_black));
else
if ((pixel >= low_white) && (pixel <= high_white))
q[i]=QuantumRange;
else
if ((pixel > high_white) && (pixel <= high_black))
q[i]=ClampToQuantum(QuantumRange*PerceptibleReciprocal(
high_black-high_white)*(high_black-pixel));
else
if (pixel > high_black)
q[i]=(Quantum) 0;
else
q[i]=(Quantum) 0;
}
q+=GetPixelChannels(image);
}
if (SyncCacheViewAuthenticPixels(image_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,ThresholdImageTag,progress,
image->rows);
if (proceed == MagickFalse)
status=MagickFalse;
}
}
image_view=DestroyCacheView(image_view);
return(status);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% W h i t e T h r e s h o l d I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% WhiteThresholdImage() is like ThresholdImage() but forces all pixels above
% the threshold into white while leaving all pixels at or below the threshold
% unchanged.
%
% The format of the WhiteThresholdImage method is:
%
% MagickBooleanType WhiteThresholdImage(Image *image,
% const char *threshold,ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the image.
%
% o threshold: Define the threshold value.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickExport MagickBooleanType WhiteThresholdImage(Image *image,
const char *thresholds,ExceptionInfo *exception)
{
#define ThresholdImageTag "Threshold/Image"
CacheView
*image_view;
GeometryInfo
geometry_info;
MagickBooleanType
status;
MagickOffsetType
progress;
PixelInfo
threshold;
MagickStatusType
flags;
ssize_t
y;
assert(image != (Image *) NULL);
assert(image->signature == MagickCoreSignature);
if (image->debug != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
if (thresholds == (const char *) NULL)
return(MagickTrue);
if (SetImageStorageClass(image,DirectClass,exception) == MagickFalse)
return(MagickFalse);
if (IsGrayColorspace(image->colorspace) != MagickFalse)
(void) TransformImageColorspace(image,sRGBColorspace,exception);
GetPixelInfo(image,&threshold);
flags=ParseGeometry(thresholds,&geometry_info);
threshold.red=geometry_info.rho;
threshold.green=geometry_info.rho;
threshold.blue=geometry_info.rho;
threshold.black=geometry_info.rho;
threshold.alpha=100.0;
if ((flags & SigmaValue) != 0)
threshold.green=geometry_info.sigma;
if ((flags & XiValue) != 0)
threshold.blue=geometry_info.xi;
if ((flags & PsiValue) != 0)
threshold.alpha=geometry_info.psi;
if (threshold.colorspace == CMYKColorspace)
{
if ((flags & PsiValue) != 0)
threshold.black=geometry_info.psi;
if ((flags & ChiValue) != 0)
threshold.alpha=geometry_info.chi;
}
if ((flags & PercentValue) != 0)
{
threshold.red*=(MagickRealType) (QuantumRange/100.0);
threshold.green*=(MagickRealType) (QuantumRange/100.0);
threshold.blue*=(MagickRealType) (QuantumRange/100.0);
threshold.black*=(MagickRealType) (QuantumRange/100.0);
threshold.alpha*=(MagickRealType) (QuantumRange/100.0);
}
/*
White threshold image.
*/
status=MagickTrue;
progress=0;
image_view=AcquireAuthenticCacheView(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(static) shared(progress,status) \
magick_number_threads(image,image,image->rows,1)
#endif
for (y=0; y < (ssize_t) image->rows; y++)
{
ssize_t
x;
Quantum
*magick_restrict q;
if (status == MagickFalse)
continue;
q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
if (q == (Quantum *) NULL)
{
status=MagickFalse;
continue;
}
for (x=0; x < (ssize_t) image->columns; x++)
{
double
pixel;
ssize_t
i;
pixel=GetPixelIntensity(image,q);
for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
{
PixelChannel channel = GetPixelChannelChannel(image,i);
PixelTrait traits = GetPixelChannelTraits(image,channel);
if ((traits & UpdatePixelTrait) == 0)
continue;
if (image->channel_mask != DefaultChannels)
pixel=(double) q[i];
if (pixel > GetPixelInfoChannel(&threshold,channel))
q[i]=QuantumRange;
}
q+=GetPixelChannels(image);
}
if (SyncCacheViewAuthenticPixels(image_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,ThresholdImageTag,progress,image->rows);
if (proceed == MagickFalse)
status=MagickFalse;
}
}
image_view=DestroyCacheView(image_view);
return(status);
}
Reference in new issue View Git Blame Copy Permalink