threshold.c File Reference

#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/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"

Include dependency graph for threshold.c:

Go to the source code of this file.

Data Structures
struct	_ThresholdMap

Macros
#define	ThresholdsFilename   "thresholds.xml"
#define	AdaptiveThresholdImageTag   "AdaptiveThreshold/Image"
#define	MaxIntensity   255
#define	ThresholdImageTag   "Threshold/Image"
#define	ThresholdImageTag   "Threshold/Image"
#define	ClampImageTag   "Clamp/Image"
#define	ThresholdImageTag   "Threshold/Image"
#define	DitherImageTag   "Dither/Image"
#define	PerceptibleImageTag   "Perceptible/Image"
#define	ThresholdImageTag   "Threshold/Image"
#define	ThresholdImageTag   "Threshold/Image"
#define	ThresholdImageTag   "Threshold/Image"

Functions
static ThresholdMap *	GetThresholdMapFile (const char *, const char *, const char *, ExceptionInfo *)
MagickExport Image *	AdaptiveThresholdImage (const Image *image, const size_t width, const size_t height, const double bias, ExceptionInfo *exception)
static double	KapurThreshold (const Image *image, const double *histogram, ExceptionInfo *exception)
static double	OTSUThreshold (const Image *image, const double *histogram, ExceptionInfo *exception)
static double	TriangleThreshold (const double *histogram)
MagickExport MagickBooleanType	AutoThresholdImage (Image *image, const AutoThresholdMethod method, ExceptionInfo *exception)
MagickExport MagickBooleanType	BilevelImage (Image *image, const double threshold, ExceptionInfo *exception)
MagickExport MagickBooleanType	BlackThresholdImage (Image *image, const char *thresholds, ExceptionInfo *exception)
MagickExport MagickBooleanType	ClampImage (Image *image, ExceptionInfo *exception)
MagickExport MagickBooleanType	ColorThresholdImage (Image *image, const PixelInfo *start_color, const PixelInfo *stop_color, ExceptionInfo *exception)
MagickExport ThresholdMap *	DestroyThresholdMap (ThresholdMap *map)
MagickExport ThresholdMap *	GetThresholdMap (const char *map_id, ExceptionInfo *exception)
MagickBooleanType	ListThresholdMapFile (FILE *file, const char *xml, const char *filename, ExceptionInfo *exception)
MagickExport MagickBooleanType	ListThresholdMaps (FILE *file, ExceptionInfo *exception)
MagickExport MagickBooleanType	OrderedDitherImage (Image *image, const char *threshold_map, ExceptionInfo *exception)
static Quantum	PerceptibleThreshold (const Quantum quantum, const double epsilon)
MagickExport MagickBooleanType	PerceptibleImage (Image *image, const double epsilon, ExceptionInfo *exception)
MagickExport MagickBooleanType	RandomThresholdImage (Image *image, const double min_threshold, const double max_threshold, ExceptionInfo *exception)
MagickExport MagickBooleanType	RangeThresholdImage (Image *image, const double low_black, const double low_white, const double high_white, const double high_black, ExceptionInfo *exception)
MagickExport MagickBooleanType	WhiteThresholdImage (Image *image, const char *thresholds, ExceptionInfo *exception)

Variables
static const char *const	BuiltinMap

Macro Definition Documentation

AdaptiveThresholdImageTag

#define AdaptiveThresholdImageTag   "AdaptiveThreshold/Image"

ClampImageTag

#define ClampImageTag   "Clamp/Image"

DitherImageTag

#define DitherImageTag   "Dither/Image"

MaxIntensity

#define MaxIntensity   255

PerceptibleImageTag

#define PerceptibleImageTag   "Perceptible/Image"

ThresholdImageTag [1/6]

#define ThresholdImageTag   "Threshold/Image"

ThresholdImageTag [2/6]

#define ThresholdImageTag   "Threshold/Image"

ThresholdImageTag [3/6]

#define ThresholdImageTag   "Threshold/Image"

ThresholdImageTag [4/6]

#define ThresholdImageTag   "Threshold/Image"

ThresholdImageTag [5/6]

#define ThresholdImageTag   "Threshold/Image"

ThresholdImageTag [6/6]

#define ThresholdImageTag   "Threshold/Image"

ThresholdsFilename

#define ThresholdsFilename   "thresholds.xml"

Definition at line 96 of file threshold.c.

Function Documentation

AdaptiveThresholdImage()

MagickExport Image * AdaptiveThresholdImage	(	const Image *	image,
		const size_t	width,
		const size_t	height,
		const double	bias,
		ExceptionInfo *	exception
	)

Definition at line 182 of file threshold.c.

References AcquireAuthenticCacheView(), AcquireVirtualCacheView(), AdaptiveThresholdImageTag, CloneImage(), _Image::columns, CopyPixelTrait, DestroyCacheView(), DestroyImage(), DirectClass, _Image::filename, GetCacheViewVirtualPixels(), GetMagickModule, GetPixelChannelChannel(), GetPixelChannels(), GetPixelChannelTraits(), IsEventLogging(), LogMagickEvent(), magick_restrict, MagickCoreSignature, MagickFalse, MagickTrue, MaxPixelChannels, _Image::progress_monitor, QuantumRange, QueueCacheViewAuthenticPixels(), _Image::rows, SetImageProgress(), SetImageStorageClass(), SetPixelChannel(), _ExceptionInfo::signature, _Image::signature, SyncCacheViewAuthenticPixels(), TraceEvent, _Image::type, and UndefinedPixelTrait.

AutoThresholdImage()

MagickExport MagickBooleanType AutoThresholdImage	(	Image *	image,
		const AutoThresholdMethod	method,
		ExceptionInfo *	exception
	)

Definition at line 661 of file threshold.c.

References AcquireQuantumMemory(), AcquireVirtualCacheView(), BilevelImage(), ClampToQuantum(), _Image::columns, DestroyCacheView(), _Image::filename, FormatLocaleFile(), FormatLocaleString(), GetCacheViewVirtualPixels(), GetImageArtifact(), GetMagickModule, GetMagickPrecision(), GetPixelChannels(), GetPixelIntensity(), IsEventLogging(), IsStringTrue(), KapurThreshold(), KapurThresholdMethod, LogMagickEvent(), magick_restrict, MagickCoreSignature, MagickFalse, MagickPathExtent, MagickTrue, MaxIntensity, OTSUThreshold(), OTSUThresholdMethod, PerceptibleReciprocal(), QuantumRange, RelinquishMagickMemory(), ResourceLimitError, _Image::rows, SetImageProperty(), _Image::signature, ThrowBinaryException, TraceEvent, TriangleThreshold(), and TriangleThresholdMethod.

BilevelImage()

MagickExport MagickBooleanType BilevelImage	(	Image *	image,
		const double	threshold,
		ExceptionInfo *	exception
	)

Definition at line 806 of file threshold.c.

References AcquireAuthenticCacheView(), _Image::channel_mask, _Image::colorspace, _Image::columns, DefaultChannels, DestroyCacheView(), DirectClass, _Image::filename, GetCacheViewAuthenticPixels(), GetMagickModule, GetPixelChannelChannel(), GetPixelChannels(), GetPixelChannelTraits(), GetPixelIntensity(), IsEventLogging(), IsGrayColorspace(), LogMagickEvent(), magick_restrict, MagickCoreSignature, MagickFalse, MagickTrue, _Image::progress_monitor, QuantumRange, _Image::rows, SetImageColorspace(), SetImageProgress(), SetImageStorageClass(), _Image::signature, sRGBColorspace, SyncCacheViewAuthenticPixels(), ThresholdImageTag, TraceEvent, and UpdatePixelTrait.

Referenced by AutoThresholdImage(), PreviewImage(), and SetImageType().

BlackThresholdImage()

MagickExport MagickBooleanType BlackThresholdImage	(	Image *	image,
		const char *	thresholds,
		ExceptionInfo *	exception
	)

Definition at line 928 of file threshold.c.

References AcquireAuthenticCacheView(), _PixelInfo::alpha, _PixelInfo::black, _PixelInfo::blue, _Image::channel_mask, _GeometryInfo::chi, ChiValue, CMYKColorspace, _Image::colorspace, _PixelInfo::colorspace, _Image::columns, DefaultChannels, DestroyCacheView(), DirectClass, _Image::filename, GetCacheViewAuthenticPixels(), GetMagickModule, GetPixelChannelChannel(), GetPixelChannels(), GetPixelChannelTraits(), GetPixelInfo(), GetPixelInfoChannel(), GetPixelIntensity(), _PixelInfo::green, IsEventLogging(), IsGrayColorspace(), LogMagickEvent(), magick_restrict, MagickCoreSignature, MagickFalse, MagickTrue, ParseGeometry(), PercentValue, _Image::progress_monitor, _GeometryInfo::psi, PsiValue, QuantumRange, _PixelInfo::red, _GeometryInfo::rho, _Image::rows, SetImageColorspace(), SetImageProgress(), SetImageStorageClass(), _GeometryInfo::sigma, SigmaValue, _Image::signature, sRGBColorspace, SyncCacheViewAuthenticPixels(), ThresholdImageTag, TraceEvent, UpdatePixelTrait, _GeometryInfo::xi, and XiValue.

ClampImage()

MagickExport MagickBooleanType ClampImage	(	Image *	image,
		ExceptionInfo *	exception
	)

Definition at line 1088 of file threshold.c.

References AcquireAuthenticCacheView(), ClampImageTag, ClampPixel(), _Image::colormap, _Image::colors, _Image::columns, DestroyCacheView(), _Image::filename, GetCacheViewAuthenticPixels(), GetMagickModule, GetPixelChannelChannel(), GetPixelChannels(), GetPixelChannelTraits(), IsEventLogging(), LogMagickEvent(), magick_restrict, MagickCoreSignature, MagickFalse, MagickTrue, _Image::progress_monitor, PseudoClass, _PixelInfo::red, _Image::rows, SetImageProgress(), _Image::signature, _Image::storage_class, SyncCacheViewAuthenticPixels(), SyncImage(), TraceEvent, and UpdatePixelTrait.

Referenced by CharcoalImage(), LevelImage(), and SketchImage().

ColorThresholdImage()

MagickExport MagickBooleanType ColorThresholdImage	(	Image *	image,
		const PixelInfo *	start_color,
		const PixelInfo *	stop_color,
		ExceptionInfo *	exception
	)

Definition at line 1218 of file threshold.c.

References AcquireAuthenticCacheView(), AcquireImageColormap(), _PixelInfo::blue, _Image::colorspace, _Image::columns, ConvertRGBToHCL(), ConvertRGBToHSB(), ConvertRGBToHSL(), ConvertRGBToHSV(), ConvertRGBToHWB(), ConvertRGBToLab(), D65Illuminant, DestroyCacheView(), _Image::filename, GetCacheViewAuthenticPixels(), GetImageArtifact(), GetMagickModule, GetPixelChannelChannel(), GetPixelChannels(), GetPixelChannelTraits(), GetPixelInfoChannel(), _PixelInfo::green, HCLColorspace, HSBColorspace, HSLColorspace, HSVColorspace, HWBColorspace, IsEventLogging(), LabColorspace, LogMagickEvent(), magick_restrict, MagickCoreSignature, MagickFalse, MagickIlluminantOptions, MagickTrue, ParseCommandOption(), _Image::progress_monitor, QuantumRange, QuantumScale, _PixelInfo::red, _Image::rows, SetImageProgress(), SetPixelIndex(), _Image::signature, sRGBColorspace, SyncCacheViewAuthenticPixels(), SyncImage(), ThresholdImageTag, TraceEvent, UndefinedIlluminant, and UpdatePixelTrait.

DestroyThresholdMap()

MagickExport ThresholdMap * DestroyThresholdMap

(

ThresholdMap *

map

)

Definition at line 1420 of file threshold.c.

References _ThresholdMap::description, DestroyString(), _ThresholdMap::levels, _ThresholdMap::map_id, and RelinquishMagickMemory().

Referenced by GetThresholdMapFile(), and OrderedDitherImage().

GetThresholdMap()

MagickExport ThresholdMap * GetThresholdMap	(	const char *	map_id,
		ExceptionInfo *	exception
	)

Definition at line 1459 of file threshold.c.

References BuiltinMap, DestroyConfigureOptions(), GetConfigureOptions(), GetNextValueInLinkedList(), GetStringInfoDatum(), GetStringInfoPath(), GetThresholdMapFile(), and ThresholdsFilename.

Referenced by OrderedDitherImage().

GetThresholdMapFile()

static ThresholdMap * GetThresholdMapFile ( const char *  xml, const char *  filename, const char *  map_id, ExceptionInfo *  exception  )

static

Definition at line 1522 of file threshold.c.

References AcquireCriticalMemory(), AcquireQuantumMemory(), ConfigureEvent, ConstantString(), _ThresholdMap::description, DestroyThresholdMap(), DestroyXMLTree(), _ThresholdMap::divisor, GetMagickModule, GetNextXMLTreeTag(), GetXMLTreeAttribute(), GetXMLTreeChild(), GetXMLTreeContent(), _ThresholdMap::height, _ThresholdMap::levels, LocaleCompare(), LogMagickEvent(), _ThresholdMap::map_id, NewXMLTree(), OptionError, ResourceLimitFatalError, StringToLong(), StringToUnsignedLong(), ThrowFatalException, ThrowMagickException(), and _ThresholdMap::width.

Referenced by GetThresholdMap().

KapurThreshold()

static double KapurThreshold ( const Image *  image, const double *  histogram, ExceptionInfo *  exception  )

static

Definition at line 393 of file threshold.c.

References AcquireQuantumMemory(), _Image::filename, GetMagickModule, MagickMinimumValue, MaxIntensity, RelinquishMagickMemory(), ResourceLimitError, and ThrowMagickException().

Referenced by AutoThresholdImage().

ListThresholdMapFile()

MagickBooleanType ListThresholdMapFile	(	FILE *	file,
		const char *	xml,
		const char *	filename,
		ExceptionInfo *	exception
	)

Definition at line 1728 of file threshold.c.

References ConfigureEvent, DestroyXMLTree(), FormatLocaleFile(), GetMagickModule, GetNextXMLTreeTag(), GetXMLTreeAttribute(), GetXMLTreeChild(), GetXMLTreeContent(), LogMagickEvent(), MagickFalse, MagickTrue, NewXMLTree(), OptionError, and ThrowMagickException().

Referenced by ListThresholdMaps().

ListThresholdMaps()

MagickExport MagickBooleanType ListThresholdMaps	(	FILE *	file,
		ExceptionInfo *	exception
	)

Definition at line 1812 of file threshold.c.

References DestroyConfigureOptions(), FormatLocaleFile(), GetConfigureOptions(), GetNextValueInLinkedList(), GetStringInfoDatum(), GetStringInfoPath(), ListThresholdMapFile(), MagickFalse, MagickTrue, and ThresholdsFilename.

OrderedDitherImage()

MagickExport MagickBooleanType OrderedDitherImage	(	Image *	image,
		const char *	threshold_map,
		ExceptionInfo *	exception
	)

Definition at line 1889 of file threshold.c.

References AcquireAuthenticCacheView(), ClampToQuantum(), _Image::columns, CompositePixelChannel, DestroyCacheView(), DestroyThresholdMap(), DirectClass, DitherImageTag, _ThresholdMap::divisor, _Image::filename, GetCacheViewAuthenticPixels(), GetMagickModule, GetNextToken(), GetPixelChannelChannel(), GetPixelChannels(), GetPixelChannelTraits(), GetThresholdMap(), _ThresholdMap::height, IsEventLogging(), _ThresholdMap::levels, LogMagickEvent(), magick_restrict, MagickCoreSignature, MagickEpsilon, MagickFalse, MagickPathExtent, MagickTrue, MaxPixelChannels, OptionError, _Image::progress_monitor, QuantumRange, QuantumScale, _Image::rows, SetImageProgress(), SetImageStorageClass(), _ExceptionInfo::signature, _Image::signature, StringToDouble(), SyncCacheViewAuthenticPixels(), ThrowMagickException(), TraceEvent, UpdatePixelTrait, and _ThresholdMap::width.

OTSUThreshold()

static double OTSUThreshold ( const Image *  image, const double *  histogram, ExceptionInfo *  exception  )

static

Definition at line 492 of file threshold.c.

References AcquireQuantumMemory(), _Image::filename, GetMagickModule, MaxIntensity, RelinquishMagickMemory(), ResourceLimitError, and ThrowMagickException().

Referenced by AutoThresholdImage().

PerceptibleImage()

MagickExport MagickBooleanType PerceptibleImage	(	Image *	image,
		const double	epsilon,
		ExceptionInfo *	exception
	)

Definition at line 2087 of file threshold.c.

References AcquireAuthenticCacheView(), ClampToQuantum(), _Image::colormap, _Image::colors, _Image::columns, DestroyCacheView(), _Image::filename, GetCacheViewAuthenticPixels(), GetMagickModule, GetPixelChannelChannel(), GetPixelChannels(), GetPixelChannelTraits(), IsEventLogging(), LogMagickEvent(), magick_restrict, MagickCoreSignature, MagickFalse, MagickTrue, PerceptibleImageTag, PerceptibleThreshold(), _Image::progress_monitor, PseudoClass, _PixelInfo::red, _Image::rows, SetImageProgress(), _Image::signature, _Image::storage_class, SyncCacheViewAuthenticPixels(), SyncImage(), TraceEvent, and UndefinedPixelTrait.

PerceptibleThreshold()

static Quantum PerceptibleThreshold ( const Quantum  quantum, const double  epsilon  )

inlinestatic

Definition at line 2075 of file threshold.c.

Referenced by PerceptibleImage().

RandomThresholdImage()

MagickExport MagickBooleanType RandomThresholdImage	(	Image *	image,
		const double	min_threshold,
		const double	max_threshold,
		ExceptionInfo *	exception
	)

Definition at line 2223 of file threshold.c.

References AcquireAuthenticCacheView(), AcquireRandomInfoTLS(), _Image::columns, DestroyCacheView(), DestroyRandomInfoTLS(), DirectClass, _Image::filename, GetCacheViewAuthenticPixels(), GetMagickModule, GetOpenMPThreadId(), GetPixelChannelChannel(), GetPixelChannels(), GetPixelChannelTraits(), GetPseudoRandomValue(), GetRandomSecretKey(), IsEventLogging(), LogMagickEvent(), magick_restrict, MagickCoreSignature, MagickFalse, MagickTrue, _Image::progress_monitor, QuantumRange, random_info, _Image::rows, SetImageProgress(), SetImageStorageClass(), _ExceptionInfo::signature, _Image::signature, SyncCacheViewAuthenticPixels(), ThresholdImageTag, TraceEvent, and UpdatePixelTrait.

RangeThresholdImage()

MagickExport MagickBooleanType RangeThresholdImage	(	Image *	image,
		const double	low_black,
		const double	low_white,
		const double	high_white,
		const double	high_black,
		ExceptionInfo *	exception
	)

Definition at line 2369 of file threshold.c.

References AcquireAuthenticCacheView(), _Image::channel_mask, ClampToQuantum(), _Image::colorspace, _Image::columns, DefaultChannels, DestroyCacheView(), DirectClass, _Image::filename, GetCacheViewAuthenticPixels(), GetMagickModule, GetPixelChannelChannel(), GetPixelChannels(), GetPixelChannelTraits(), GetPixelIntensity(), IsEventLogging(), IsGrayColorspace(), LogMagickEvent(), magick_restrict, MagickCoreSignature, MagickFalse, MagickTrue, PerceptibleReciprocal(), _Image::progress_monitor, QuantumRange, _Image::rows, SetImageProgress(), SetImageStorageClass(), _Image::signature, sRGBColorspace, SyncCacheViewAuthenticPixels(), ThresholdImageTag, TraceEvent, TransformImageColorspace(), and UpdatePixelTrait.

TriangleThreshold()

static double TriangleThreshold ( const double *  histogram )

static

Definition at line 571 of file threshold.c.

References MaxIntensity.

Referenced by AutoThresholdImage().

WhiteThresholdImage()

MagickExport MagickBooleanType WhiteThresholdImage	(	Image *	image,
		const char *	thresholds,
		ExceptionInfo *	exception
	)

Definition at line 2509 of file threshold.c.

References AcquireAuthenticCacheView(), _PixelInfo::alpha, _PixelInfo::black, _PixelInfo::blue, _Image::channel_mask, _GeometryInfo::chi, ChiValue, CMYKColorspace, _Image::colorspace, _PixelInfo::colorspace, _Image::columns, DefaultChannels, DestroyCacheView(), DirectClass, _Image::filename, GetCacheViewAuthenticPixels(), GetMagickModule, GetPixelChannelChannel(), GetPixelChannels(), GetPixelChannelTraits(), GetPixelInfo(), GetPixelInfoChannel(), GetPixelIntensity(), _PixelInfo::green, IsEventLogging(), IsGrayColorspace(), LogMagickEvent(), magick_restrict, MagickCoreSignature, MagickFalse, MagickTrue, ParseGeometry(), PercentValue, _Image::progress_monitor, _GeometryInfo::psi, PsiValue, QuantumRange, _PixelInfo::red, _GeometryInfo::rho, _Image::rows, SetImageProgress(), SetImageStorageClass(), _GeometryInfo::sigma, SigmaValue, _Image::signature, sRGBColorspace, SyncCacheViewAuthenticPixels(), ThresholdImageTag, TraceEvent, TransformImageColorspace(), UpdatePixelTrait, _GeometryInfo::xi, and XiValue.

Variable Documentation

BuiltinMap

const char* const BuiltinMap

static

Initial value:

=
    "<?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>"

Definition at line 123 of file threshold.c.

Referenced by GetThresholdMap().