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gerrit-public.fairphone.software / platform / external / ImageMagick / b7b531efdad3ff916a12ab2b6a52bed18be80731 / . / magick / morphology.c
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/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% M M OOO RRRR PPPP H H OOO L OOO GGGG Y Y %
% MM MM O O R R P P H H O O L O O G Y Y %
% M M M O O RRRR PPPP HHHHH O O L O O G GGG Y %
% M M O O R R P H H O O L O O G G Y %
% M M OOO R R P H H OOO LLLLL OOO GGG Y %
% %
% %
% MagickCore Morphology Methods %
% %
% Software Design %
% Anthony Thyssen %
% January 2010 %
% %
% %
% Copyright 1999-2010 ImageMagick Studio LLC, a non-profit organization %
% dedicated to making software imaging solutions freely available. %
% %
% You may not use this file except in compliance with the License. You may %
% obtain a copy of the License at %
% %
% http://www.imagemagick.org/script/license.php %
% %
% Unless required by applicable law or agreed to in writing, software %
% distributed under the License is distributed on an "AS IS" BASIS, %
% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. %
% See the License for the specific language governing permissions and %
% limitations under the License. %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Morpology is the the application of various kernels, of any size and even
% shape, to a image in various ways (typically binary, but not always).
%
% Convolution (weighted sum or average) is just one specific type of
% morphology. Just one that is very common for image bluring and sharpening
% effects. Not only 2D Gaussian blurring, but also 2-pass 1D Blurring.
%
% This module provides not only a general morphology function, and the ability
% to apply more advanced or iterative morphologies, but also functions for the
% generation of many different types of kernel arrays from user supplied
% arguments. Prehaps even the generation of a kernel from a small image.
*/
/*
Include declarations.
*/
#include "magick/studio.h"
#include "magick/artifact.h"
#include "magick/cache-view.h"
#include "magick/color-private.h"
#include "magick/enhance.h"
#include "magick/exception.h"
#include "magick/exception-private.h"
#include "magick/gem.h"
#include "magick/hashmap.h"
#include "magick/image.h"
#include "magick/image-private.h"
#include "magick/list.h"
#include "magick/magick.h"
#include "magick/memory_.h"
#include "magick/monitor-private.h"
#include "magick/morphology.h"
#include "magick/morphology-private.h"
#include "magick/option.h"
#include "magick/pixel-private.h"
#include "magick/prepress.h"
#include "magick/quantize.h"
#include "magick/registry.h"
#include "magick/semaphore.h"
#include "magick/splay-tree.h"
#include "magick/statistic.h"
#include "magick/string_.h"
#include "magick/string-private.h"
#include "magick/token.h"
/*
** The following test is for special floating point numbers of value NaN (not
** a number), that may be used within a Kernel Definition. NaN's are defined
** as part of the IEEE standard for floating point number representation.
**
** These are used as a Kernel value to mean that this kernel position is not
** part of the kernel neighbourhood for convolution or morphology processing,
** and thus should be ignored. This allows the use of 'shaped' kernels.
**
** The special properity that two NaN's are never equal, even if they are from
** the same variable allow you to test if a value is special NaN value.
**
** This macro IsNaN() is thus is only true if the value given is NaN.
*/
#define IsNan(a) ((a)!=(a))
/*
Other global definitions used by module.
*/
static inline double MagickMin(const double x,const double y)
{
return( x < y ? x : y);
}
static inline double MagickMax(const double x,const double y)
{
return( x > y ? x : y);
}
#define Minimize(assign,value) assign=MagickMin(assign,value)
#define Maximize(assign,value) assign=MagickMax(assign,value)
/* Currently these are only internal to this module */
static void
CalcKernelMetaData(KernelInfo *),
ExpandMirrorKernelInfo(KernelInfo *),
ExpandRotateKernelInfo(KernelInfo *, const double),
RotateKernelInfo(KernelInfo *, double);
/* Quick function to find last kernel in a kernel list */
static inline KernelInfo *LastKernelInfo(KernelInfo *kernel)
{
while (kernel->next != (KernelInfo *) NULL)
kernel = kernel->next;
return(kernel);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% A c q u i r e K e r n e l I n f o %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% AcquireKernelInfo() takes the given string (generally supplied by the
% user) and converts it into a Morphology/Convolution Kernel. This allows
% users to specify a kernel from a number of pre-defined kernels, or to fully
% specify their own kernel for a specific Convolution or Morphology
% Operation.
%
% The kernel so generated can be any rectangular array of floating point
% values (doubles) with the 'control point' or 'pixel being affected'
% anywhere within that array of values.
%
% Previously IM was restricted to a square of odd size using the exact
% center as origin, this is no longer the case, and any rectangular kernel
% with any value being declared the origin. This in turn allows the use of
% highly asymmetrical kernels.
%
% The floating point values in the kernel can also include a special value
% known as 'nan' or 'not a number' to indicate that this value is not part
% of the kernel array. This allows you to shaped the kernel within its
% rectangular area. That is 'nan' values provide a 'mask' for the kernel
% shape. However at least one non-nan value must be provided for correct
% working of a kernel.
%
% The returned kernel should be freed using the DestroyKernelInfo() when you
% are finished with it. Do not free this memory yourself.
%
% Input kernel defintion strings can consist of any of three types.
%
% "name:args[[@><]"
% Select from one of the built in kernels, using the name and
% geometry arguments supplied. See AcquireKernelBuiltIn()
%
% "WxH[+X+Y][@><]:num, num, num ..."
% a kernel of size W by H, with W*H floating point numbers following.
% the 'center' can be optionally be defined at +X+Y (such that +0+0
% is top left corner). If not defined the pixel in the center, for
% odd sizes, or to the immediate top or left of center for even sizes
% is automatically selected.
%
% "num, num, num, num, ..."
% list of floating point numbers defining an 'old style' odd sized
% square kernel. At least 9 values should be provided for a 3x3
% square kernel, 25 for a 5x5 square kernel, 49 for 7x7, etc.
% Values can be space or comma separated. This is not recommended.
%
% You can define a 'list of kernels' which can be used by some morphology
% operators A list is defined as a semi-colon seperated list kernels.
%
% " kernel ; kernel ; kernel ; "
%
% Any extra ';' characters, at start, end or between kernel defintions are
% simply ignored.
%
% The special flags will expand a single kernel, into a list of rotated
% kernels. A '@' flag will expand a 3x3 kernel into a list of 45-degree
% cyclic rotations, while a '>' will generate a list of 90-degree rotations.
% The '<' also exands using 90-degree rotates, but giving a 180-degree
% reflected kernel before the +/- 90-degree rotations, which can be important
% for Thinning operations.
%
% Note that 'name' kernels will start with an alphabetic character while the
% new kernel specification has a ':' character in its specification string.
% If neither is the case, it is assumed an old style of a simple list of
% numbers generating a odd-sized square kernel has been given.
%
% The format of the AcquireKernal method is:
%
% KernelInfo *AcquireKernelInfo(const char *kernel_string)
%
% A description of each parameter follows:
%
% o kernel_string: the Morphology/Convolution kernel wanted.
%
*/
/* This was separated so that it could be used as a separate
** array input handling function, such as for -color-matrix
*/
static KernelInfo *ParseKernelArray(const char *kernel_string)
{
KernelInfo
*kernel;
char
token[MaxTextExtent];
const char
*p,
*end;
register ssize_t
i;
double
nan = sqrt((double)-1.0); /* Special Value : Not A Number */
MagickStatusType
flags;
GeometryInfo
args;
kernel=(KernelInfo *) AcquireMagickMemory(sizeof(*kernel));
if (kernel == (KernelInfo *)NULL)
return(kernel);
(void) ResetMagickMemory(kernel,0,sizeof(*kernel));
kernel->minimum = kernel->maximum = kernel->angle = 0.0;
kernel->negative_range = kernel->positive_range = 0.0;
kernel->type = UserDefinedKernel;
kernel->next = (KernelInfo *) NULL;
kernel->signature = MagickSignature;
/* find end of this specific kernel definition string */
end = strchr(kernel_string, ';');
if ( end == (char *) NULL )
end = strchr(kernel_string, '\0');
/* clear flags - for Expanding kernal lists thorugh rotations */
flags = NoValue;
/* Has a ':' in argument - New user kernel specification */
p = strchr(kernel_string, ':');
if ( p != (char *) NULL && p < end)
{
/* ParseGeometry() needs the geometry separated! -- Arrgghh */
memcpy(token, kernel_string, (size_t) (p-kernel_string));
token[p-kernel_string] = '\0';
SetGeometryInfo(&args);
flags = ParseGeometry(token, &args);
/* Size handling and checks of geometry settings */
if ( (flags & WidthValue) == 0 ) /* if no width then */
args.rho = args.sigma; /* then width = height */
if ( args.rho < 1.0 ) /* if width too small */
args.rho = 1.0; /* then width = 1 */
if ( args.sigma < 1.0 ) /* if height too small */
args.sigma = args.rho; /* then height = width */
kernel->width = (size_t)args.rho;
kernel->height = (size_t)args.sigma;
/* Offset Handling and Checks */
if ( args.xi < 0.0 || args.psi < 0.0 )
return(DestroyKernelInfo(kernel));
kernel->x = ((flags & XValue)!=0) ? (ssize_t)args.xi
: (ssize_t) (kernel->width-1)/2;
kernel->y = ((flags & YValue)!=0) ? (ssize_t)args.psi
: (ssize_t) (kernel->height-1)/2;
if ( kernel->x >= (ssize_t) kernel->width ||
kernel->y >= (ssize_t) kernel->height )
return(DestroyKernelInfo(kernel));
p++; /* advance beyond the ':' */
}
else
{ /* ELSE - Old old specification, forming odd-square kernel */
/* count up number of values given */
p=(const char *) kernel_string;
while ((isspace((int) ((unsigned char) *p)) != 0) || (*p == '\''))
p++; /* ignore "'" chars for convolve filter usage - Cristy */
for (i=0; p < end; i++)
{
GetMagickToken(p,&p,token);
if (*token == ',')
GetMagickToken(p,&p,token);
}
/* set the size of the kernel - old sized square */
kernel->width = kernel->height= (size_t) sqrt((double) i+1.0);
kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
p=(const char *) kernel_string;
while ((isspace((int) ((unsigned char) *p)) != 0) || (*p == '\''))
p++; /* ignore "'" chars for convolve filter usage - Cristy */
}
/* Read in the kernel values from rest of input string argument */
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
kernel->minimum = +MagickHuge;
kernel->maximum = -MagickHuge;
kernel->negative_range = kernel->positive_range = 0.0;
for (i=0; (i < (ssize_t) (kernel->width*kernel->height)) && (p < end); i++)
{
GetMagickToken(p,&p,token);
if (*token == ',')
GetMagickToken(p,&p,token);
if ( LocaleCompare("nan",token) == 0
|| LocaleCompare("-",token) == 0 ) {
kernel->values[i] = nan; /* do not include this value in kernel */
}
else {
kernel->values[i] = StringToDouble(token);
( kernel->values[i] < 0)
? ( kernel->negative_range += kernel->values[i] )
: ( kernel->positive_range += kernel->values[i] );
Minimize(kernel->minimum, kernel->values[i]);
Maximize(kernel->maximum, kernel->values[i]);
}
}
/* sanity check -- no more values in kernel definition */
GetMagickToken(p,&p,token);
if ( *token != '\0' && *token != ';' && *token != '\'' )
return(DestroyKernelInfo(kernel));
#if 0
/* this was the old method of handling a incomplete kernel */
if ( i < (ssize_t) (kernel->width*kernel->height) ) {
Minimize(kernel->minimum, kernel->values[i]);
Maximize(kernel->maximum, kernel->values[i]);
for ( ; i < (ssize_t) (kernel->width*kernel->height); i++)
kernel->values[i]=0.0;
}
#else
/* Number of values for kernel was not enough - Report Error */
if ( i < (ssize_t) (kernel->width*kernel->height) )
return(DestroyKernelInfo(kernel));
#endif
/* check that we recieved at least one real (non-nan) value! */
if ( kernel->minimum == MagickHuge )
return(DestroyKernelInfo(kernel));
if ( (flags & AreaValue) != 0 ) /* '@' symbol in kernel size */
ExpandRotateKernelInfo(kernel, 45.0); /* cyclic rotate 3x3 kernels */
else if ( (flags & GreaterValue) != 0 ) /* '>' symbol in kernel args */
ExpandRotateKernelInfo(kernel, 90.0); /* 90 degree rotate of kernel */
else if ( (flags & LessValue) != 0 ) /* '<' symbol in kernel args */
ExpandMirrorKernelInfo(kernel); /* 90 degree mirror rotate */
return(kernel);
}
static KernelInfo *ParseKernelName(const char *kernel_string)
{
KernelInfo
*kernel;
char
token[MaxTextExtent];
ssize_t
type;
const char
*p,
*end;
MagickStatusType
flags;
GeometryInfo
args;
/* Parse special 'named' kernel */
GetMagickToken(kernel_string,&p,token);
type=ParseMagickOption(MagickKernelOptions,MagickFalse,token);
if ( type < 0 || type == UserDefinedKernel )
return((KernelInfo *)NULL); /* not a valid named kernel */
while (((isspace((int) ((unsigned char) *p)) != 0) ||
(*p == ',') || (*p == ':' )) && (*p != '\0') && (*p != ';'))
p++;
end = strchr(p, ';'); /* end of this kernel defintion */
if ( end == (char *) NULL )
end = strchr(p, '\0');
/* ParseGeometry() needs the geometry separated! -- Arrgghh */
memcpy(token, p, (size_t) (end-p));
token[end-p] = '\0';
SetGeometryInfo(&args);
flags = ParseGeometry(token, &args);
#if 0
/* For Debugging Geometry Input */
fprintf(stderr, "Geometry = 0x%04X : %lg x %lg %+lg %+lg\n",
flags, args.rho, args.sigma, args.xi, args.psi );
#endif
/* special handling of missing values in input string */
switch( type ) {
case RectangleKernel:
if ( (flags & WidthValue) == 0 ) /* if no width then */
args.rho = args.sigma; /* then width = height */
if ( args.rho < 1.0 ) /* if width too small */
args.rho = 3; /* then width = 3 */
if ( args.sigma < 1.0 ) /* if height too small */
args.sigma = args.rho; /* then height = width */
if ( (flags & XValue) == 0 ) /* center offset if not defined */
args.xi = (double)(((ssize_t)args.rho-1)/2);
if ( (flags & YValue) == 0 )
args.psi = (double)(((ssize_t)args.sigma-1)/2);
break;
case SquareKernel:
case DiamondKernel:
case DiskKernel:
case PlusKernel:
case CrossKernel:
/* If no scale given (a 0 scale is valid! - set it to 1.0 */
if ( (flags & HeightValue) == 0 )
args.sigma = 1.0;
break;
case RingKernel:
if ( (flags & XValue) == 0 )
args.xi = 1.0;
break;
case ChebyshevKernel:
case ManhattanKernel:
case EuclideanKernel:
if ( (flags & HeightValue) == 0 ) /* no distance scale */
args.sigma = 100.0; /* default distance scaling */
else if ( (flags & AspectValue ) != 0 ) /* '!' flag */
args.sigma = QuantumRange/(args.sigma+1); /* maximum pixel distance */
else if ( (flags & PercentValue ) != 0 ) /* '%' flag */
args.sigma *= QuantumRange/100.0; /* percentage of color range */
break;
default:
break;
}
kernel = AcquireKernelBuiltIn((KernelInfoType)type, &args);
/* global expand to rotated kernel list - only for single kernels */
if ( kernel->next == (KernelInfo *) NULL ) {
if ( (flags & AreaValue) != 0 ) /* '@' symbol in kernel args */
ExpandRotateKernelInfo(kernel, 45.0);
else if ( (flags & GreaterValue) != 0 ) /* '>' symbol in kernel args */
ExpandRotateKernelInfo(kernel, 90.0);
else if ( (flags & LessValue) != 0 ) /* '<' symbol in kernel args */
ExpandMirrorKernelInfo(kernel);
}
return(kernel);
}
MagickExport KernelInfo *AcquireKernelInfo(const char *kernel_string)
{
KernelInfo
*kernel,
*new_kernel;
char
token[MaxTextExtent];
const char
*p;
size_t
kernel_number;
p = kernel_string;
kernel = NULL;
kernel_number = 0;
while ( GetMagickToken(p,NULL,token), *token != '\0' ) {
/* ignore extra or multiple ';' kernel seperators */
if ( *token != ';' ) {
/* tokens starting with alpha is a Named kernel */
if (isalpha((int) *token) != 0)
new_kernel = ParseKernelName(p);
else /* otherwise a user defined kernel array */
new_kernel = ParseKernelArray(p);
/* Error handling -- this is not proper error handling! */
if ( new_kernel == (KernelInfo *) NULL ) {
fprintf(stderr, "Failed to parse kernel number #%.20g\n",(double)
kernel_number);
if ( kernel != (KernelInfo *) NULL )
kernel=DestroyKernelInfo(kernel);
return((KernelInfo *) NULL);
}
/* initialise or append the kernel list */
if ( kernel == (KernelInfo *) NULL )
kernel = new_kernel;
else
LastKernelInfo(kernel)->next = new_kernel;
}
/* look for the next kernel in list */
p = strchr(p, ';');
if ( p == (char *) NULL )
break;
p++;
}
return(kernel);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% A c q u i r e K e r n e l B u i l t I n %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% AcquireKernelBuiltIn() returned one of the 'named' built-in types of
% kernels used for special purposes such as gaussian blurring, skeleton
% pruning, and edge distance determination.
%
% They take a KernelType, and a set of geometry style arguments, which were
% typically decoded from a user supplied string, or from a more complex
% Morphology Method that was requested.
%
% The format of the AcquireKernalBuiltIn method is:
%
% KernelInfo *AcquireKernelBuiltIn(const KernelInfoType type,
% const GeometryInfo args)
%
% A description of each parameter follows:
%
% o type: the pre-defined type of kernel wanted
%
% o args: arguments defining or modifying the kernel
%
% Convolution Kernels
%
% Unity
% the No-Op kernel, also requivelent to Gaussian of sigma zero.
% Basically a 3x3 kernel of a 1 surrounded by zeros.
%
% Gaussian:{radius},{sigma}
% Generate a two-dimentional gaussian kernel, as used by -gaussian.
% The sigma for the curve is required. The resulting kernel is
% normalized,
%
% If 'sigma' is zero, you get a single pixel on a field of zeros.
%
% NOTE: that the 'radius' is optional, but if provided can limit (clip)
% the final size of the resulting kernel to a square 2*radius+1 in size.
% The radius should be at least 2 times that of the sigma value, or
% sever clipping and aliasing may result. If not given or set to 0 the
% radius will be determined so as to produce the best minimal error
% result, which is usally much larger than is normally needed.
%
% LoG:{radius},{sigma}
% "Laplacian of a Gaussian" or "Mexician Hat" Kernel.
% The supposed ideal edge detection, zero-summing kernel.
%
% An alturnative to this kernel is to use a "DoG" with a sigma ratio of
% approx 1.6 (according to wikipedia).
%
% DoG:{radius},{sigma1},{sigma2}
% "Difference of Gaussians" Kernel.
% As "Gaussian" but with a gaussian produced by 'sigma2' subtracted
% from the gaussian produced by 'sigma1'. Typically sigma2 > sigma1.
% The result is a zero-summing kernel.
%
% Blur:{radius},{sigma}[,{angle}]
% Generates a 1 dimensional or linear gaussian blur, at the angle given
% (current restricted to orthogonal angles). If a 'radius' is given the
% kernel is clipped to a width of 2*radius+1. Kernel can be rotated
% by a 90 degree angle.
%
% If 'sigma' is zero, you get a single pixel on a field of zeros.
%
% Note that two convolutions with two "Blur" kernels perpendicular to
% each other, is equivelent to a far larger "Gaussian" kernel with the
% same sigma value, However it is much faster to apply. This is how the
% "-blur" operator actually works.
%
% Comet:{width},{sigma},{angle}
% Blur in one direction only, much like how a bright object leaves
% a comet like trail. The Kernel is actually half a gaussian curve,
% Adding two such blurs in opposite directions produces a Blur Kernel.
% Angle can be rotated in multiples of 90 degrees.
%
% Note that the first argument is the width of the kernel and not the
% radius of the kernel.
%
% # Still to be implemented...
% #
% # Filter2D
% # Filter1D
% # Set kernel values using a resize filter, and given scale (sigma)
% # Cylindrical or Linear. Is this posible with an image?
% #
%
% Named Constant Convolution Kernels
%
% All these are unscaled, zero-summing kernels by default. As such for
% non-HDRI version of ImageMagick some form of normalization, user scaling,
% and biasing the results is recommended, to prevent the resulting image
% being 'clipped'.
%
% The 3x3 kernels (most of these) can be circularly rotated in multiples of
% 45 degrees to generate the 8 angled varients of each of the kernels.
%
% Laplacian:{type}
% Discrete Lapacian Kernels, (without normalization)
% Type 0 : 3x3 with center:8 surounded by -1 (8 neighbourhood)
% Type 1 : 3x3 with center:4 edge:-1 corner:0 (4 neighbourhood)
% Type 2 : 3x3 with center:4 edge:1 corner:-2
% Type 3 : 3x3 with center:4 edge:-2 corner:1
% Type 5 : 5x5 laplacian
% Type 7 : 7x7 laplacian
% Type 15 : 5x5 LoG (sigma approx 1.4)
% Type 19 : 9x9 LoG (sigma approx 1.4)
%
% Sobel:{angle}
% Sobel 'Edge' convolution kernel (3x3)
% | -1, 0, 1 |
% | -2, 0,-2 |
% | -1, 0, 1 |
%
% Sobel:{type},{angle}
% Type 0: default un-nomalized version shown above.
%
% Type 1: As default but pre-normalized
% | 1, 0, -1 |
% | 2, 0, -2 | / 4
% | 1, 0, -1 |
%
% Type 2: Diagonal version with same normalization as 1
% | 1, 0, -1 |
% | 2, 0, -2 | / 4
% | 1, 0, -1 |
%
% Roberts:{angle}
% Roberts convolution kernel (3x3)
% | 0, 0, 0 |
% | -1, 1, 0 |
% | 0, 0, 0 |
%
% Prewitt:{angle}
% Prewitt Edge convolution kernel (3x3)
% | -1, 0, 1 |
% | -1, 0, 1 |
% | -1, 0, 1 |
%
% Compass:{angle}
% Prewitt's "Compass" convolution kernel (3x3)
% | -1, 1, 1 |
% | -1,-2, 1 |
% | -1, 1, 1 |
%
% Kirsch:{angle}
% Kirsch's "Compass" convolution kernel (3x3)
% | -3,-3, 5 |
% | -3, 0, 5 |
% | -3,-3, 5 |
%
% FreiChen:{angle}
% Frei-Chen Edge Detector is based on a kernel that is similar to
% the Sobel Kernel, but is designed to be isotropic. That is it takes
% into account the distance of the diagonal in the kernel.
%
% | 1, 0, -1 |
% | sqrt(2), 0, -sqrt(2) |
% | 1, 0, -1 |
%
% FreiChen:{type},{angle}
%
% Frei-Chen Pre-weighted kernels...
%
% Type 0: default un-nomalized version shown above.
%
% Type 1: Orthogonal Kernel (same as type 11 below)
% | 1, 0, -1 |
% | sqrt(2), 0, -sqrt(2) | / 2*sqrt(2)
% | 1, 0, -1 |
%
% Type 2: Diagonal form of Kernel...
% | 1, sqrt(2), 0 |
% | sqrt(2), 0, -sqrt(2) | / 2*sqrt(2)
% | 0, -sqrt(2) -1 |
%
% However this kernel is als at the heart of the FreiChen Edge Detection
% Process which uses a set of 9 specially weighted kernel. These 9
% kernels not be normalized, but directly applied to the image. The
% results is then added together, to produce the intensity of an edge in
% a specific direction. The square root of the pixel value can then be
% taken as the cosine of the edge, and at least 2 such runs at 90 degrees
% from each other, both the direction and the strength of the edge can be
% determined.
%
% Type 10: All 9 of the following pre-weighted kernels...
%
% Type 11: | 1, 0, -1 |
% | sqrt(2), 0, -sqrt(2) | / 2*sqrt(2)
% | 1, 0, -1 |
%
% Type 12: | 1, sqrt(2), 1 |
% | 0, 0, 0 | / 2*sqrt(2)
% | 1, sqrt(2), 1 |
%
% Type 13: | sqrt(2), -1, 0 |
% | -1, 0, 1 | / 2*sqrt(2)
% | 0, 1, -sqrt(2) |
%
% Type 14: | 0, 1, -sqrt(2) |
% | -1, 0, 1 | / 2*sqrt(2)
% | sqrt(2), -1, 0 |
%
% Type 15: | 0, -1, 0 |
% | 1, 0, 1 | / 2
% | 0, -1, 0 |
%
% Type 16: | 1, 0, -1 |
% | 0, 0, 0 | / 2
% | -1, 0, 1 |
%
% Type 17: | 1, -2, 1 |
% | -2, 4, -2 | / 6
% | -1, -2, 1 |
%
% Type 18: | -2, 1, -2 |
% | 1, 4, 1 | / 6
% | -2, 1, -2 |
%
% Type 19: | 1, 1, 1 |
% | 1, 1, 1 | / 3
% | 1, 1, 1 |
%
% The first 4 are for edge detection, the next 4 are for line detection
% and the last is to add a average component to the results.
%
% Using a special type of '-1' will return all 9 pre-weighted kernels
% as a multi-kernel list, so that you can use them directly (without
% normalization) with the special "-set option:morphology:compose Plus"
% setting to apply the full FreiChen Edge Detection Technique.
%
% If 'type' is large it will be taken to be an actual rotation angle for
% the default FreiChen (type 0) kernel. As such FreiChen:45 will look
% like a Sobel:45 but with 'sqrt(2)' instead of '2' values.
%
% WARNING: The above was layed out as per
% http://www.math.tau.ac.il/~turkel/notes/edge_detectors.pdf
% But rotated 90 degrees so direction is from left rather than the top.
% I have yet to find any secondary confirmation of the above. The only
% other source found was actual source code at
% http://ltswww.epfl.ch/~courstiv/exos_labos/sol3.pdf
% Neigher paper defineds the kernels in a way that looks locical or
% correct when taken as a whole.
%
% Boolean Kernels
%
% Diamond:[{radius}[,{scale}]]
% Generate a diamond shaped kernel with given radius to the points.
% Kernel size will again be radius*2+1 square and defaults to radius 1,
% generating a 3x3 kernel that is slightly larger than a square.
%
% Square:[{radius}[,{scale}]]
% Generate a square shaped kernel of size radius*2+1, and defaulting
% to a 3x3 (radius 1).
%
% Note that using a larger radius for the "Square" or the "Diamond" is
% also equivelent to iterating the basic morphological method that many
% times. However iterating with the smaller radius is actually faster
% than using a larger kernel radius.
%
% Rectangle:{geometry}
% Simply generate a rectangle of 1's with the size given. You can also
% specify the location of the 'control point', otherwise the closest
% pixel to the center of the rectangle is selected.
%
% Properly centered and odd sized rectangles work the best.
%
% Disk:[{radius}[,{scale}]]
% Generate a binary disk of the radius given, radius may be a float.
% Kernel size will be ceil(radius)*2+1 square.
% NOTE: Here are some disk shapes of specific interest
% "Disk:1" => "diamond" or "cross:1"
% "Disk:1.5" => "square"
% "Disk:2" => "diamond:2"
% "Disk:2.5" => a general disk shape of radius 2
% "Disk:2.9" => "square:2"
% "Disk:3.5" => default - octagonal/disk shape of radius 3
% "Disk:4.2" => roughly octagonal shape of radius 4
% "Disk:4.3" => a general disk shape of radius 4
% After this all the kernel shape becomes more and more circular.
%
% Because a "disk" is more circular when using a larger radius, using a
% larger radius is preferred over iterating the morphological operation.
%
% Symbol Dilation Kernels
%
% These kernel is not a good general morphological kernel, but is used
% more for highlighting and marking any single pixels in an image using,
% a "Dilate" method as appropriate.
%
% For the same reasons iterating these kernels does not produce the
% same result as using a larger radius for the symbol.
%
% Plus:[{radius}[,{scale}]]
% Cross:[{radius}[,{scale}]]
% Generate a kernel in the shape of a 'plus' or a 'cross' with
% a each arm the length of the given radius (default 2).
%
% NOTE: "plus:1" is equivelent to a "Diamond" kernel.
%
% Ring:{radius1},{radius2}[,{scale}]
% A ring of the values given that falls between the two radii.
% Defaults to a ring of approximataly 3 radius in a 7x7 kernel.
% This is the 'edge' pixels of the default "Disk" kernel,
% More specifically, "Ring" -> "Ring:2.5,3.5,1.0"
%
% Hit and Miss Kernels
%
% Peak:radius1,radius2
% Find any peak larger than the pixels the fall between the two radii.
% The default ring of pixels is as per "Ring".
% Edges
% Find flat orthogonal edges of a binary shape
% Corners
% Find 90 degree corners of a binary shape
% LineEnds:type
% Find end points of lines (for pruning a skeletion)
% Two types of lines ends (default to both) can be searched for
% Type 0: All line ends
% Type 1: single kernel for 4-conneected line ends
% Type 2: single kernel for simple line ends
% LineJunctions
% Find three line junctions (within a skeletion)
% Type 0: all line junctions
% Type 1: Y Junction kernel
% Type 2: Diagonal T Junction kernel
% Type 3: Orthogonal T Junction kernel
% Type 4: Diagonal X Junction kernel
% Type 5: Orthogonal + Junction kernel
% Ridges:type
% Find single pixel ridges or thin lines
% Type 1: Fine single pixel thick lines and ridges
% Type 2: Find two pixel thick lines and ridges
% ConvexHull
% Octagonal thicken kernel, to generate convex hulls of 45 degrees
% Skeleton:type
% Traditional skeleton generating kernels.
% Type 1: Tradional Skeleton kernel (4 connected skeleton)
% Type 2: HIPR2 Skeleton kernel (8 connected skeleton)
% Type 3: Experimental Variation to try to present left-right symmetry
% Type 4: Experimental Variation to preserve left-right symmetry
%
% Distance Measuring Kernels
%
% Different types of distance measuring methods, which are used with the
% a 'Distance' morphology method for generating a gradient based on
% distance from an edge of a binary shape, though there is a technique
% for handling a anti-aliased shape.
%
% See the 'Distance' Morphological Method, for information of how it is
% applied.
%
% Chebyshev:[{radius}][x{scale}[%!]]
% Chebyshev Distance (also known as Tchebychev Distance) is a value of
% one to any neighbour, orthogonal or diagonal. One why of thinking of
% it is the number of squares a 'King' or 'Queen' in chess needs to
% traverse reach any other position on a chess board. It results in a
% 'square' like distance function, but one where diagonals are closer
% than expected.
%
% Manhattan:[{radius}][x{scale}[%!]]
% Manhattan Distance (also known as Rectilinear Distance, or the Taxi
% Cab metric), is the distance needed when you can only travel in
% orthogonal (horizontal or vertical) only. It is the distance a 'Rook'
% in chess would travel. It results in a diamond like distances, where
% diagonals are further than expected.
%
% Euclidean:[{radius}][x{scale}[%!]]
% Euclidean Distance is the 'direct' or 'as the crow flys distance.
% However by default the kernel size only has a radius of 1, which
% limits the distance to 'Knight' like moves, with only orthogonal and
% diagonal measurements being correct. As such for the default kernel
% you will get octagonal like distance function, which is reasonally
% accurate.
%
% However if you use a larger radius such as "Euclidean:4" you will
% get a much smoother distance gradient from the edge of the shape.
% Of course a larger kernel is slower to use, and generally not needed.
%
% To allow the use of fractional distances that you get with diagonals
% the actual distance is scaled by a fixed value which the user can
% provide. This is not actually nessary for either ""Chebyshev" or
% "Manhattan" distance kernels, but is done for all three distance
% kernels. If no scale is provided it is set to a value of 100,
% allowing for a maximum distance measurement of 655 pixels using a Q16
% version of IM, from any edge. However for small images this can
% result in quite a dark gradient.
%
*/
MagickExport KernelInfo *AcquireKernelBuiltIn(const KernelInfoType type,
const GeometryInfo *args)
{
KernelInfo
*kernel;
register ssize_t
i;
register ssize_t
u,
v;
double
nan = sqrt((double)-1.0); /* Special Value : Not A Number */
/* Generate a new empty kernel if needed */
kernel=(KernelInfo *) NULL;
switch(type) {
case UndefinedKernel: /* These should not call this function */
case UserDefinedKernel:
break;
case UnityKernel: /* Named Descrete Convolution Kernels */
case LaplacianKernel:
case SobelKernel:
case RobertsKernel:
case PrewittKernel:
case CompassKernel:
case KirschKernel:
case FreiChenKernel:
case EdgesKernel: /* Hit and Miss kernels */
case CornersKernel:
case ThinDiagonalsKernel:
case LineEndsKernel:
case LineJunctionsKernel:
case RidgesKernel:
case ConvexHullKernel:
case SkeletonKernel:
break; /* A pre-generated kernel is not needed */
#if 0
/* set to 1 to do a compile-time check that we haven't missed anything */
case GaussianKernel:
case DoGKernel:
case LoGKernel:
case BlurKernel:
case CometKernel:
case DiamondKernel:
case SquareKernel:
case RectangleKernel:
case DiskKernel:
case PlusKernel:
case CrossKernel:
case RingKernel:
case PeaksKernel:
case ChebyshevKernel:
case ManhattanKernel:
case EuclideanKernel:
#else
default:
#endif
/* Generate the base Kernel Structure */
kernel=(KernelInfo *) AcquireMagickMemory(sizeof(*kernel));
if (kernel == (KernelInfo *) NULL)
return(kernel);
(void) ResetMagickMemory(kernel,0,sizeof(*kernel));
kernel->minimum = kernel->maximum = kernel->angle = 0.0;
kernel->negative_range = kernel->positive_range = 0.0;
kernel->type = type;
kernel->next = (KernelInfo *) NULL;
kernel->signature = MagickSignature;
break;
}
switch(type) {
/* Convolution Kernels */
case GaussianKernel:
case DoGKernel:
case LoGKernel:
{ double
sigma = fabs(args->sigma),
sigma2 = fabs(args->xi),
A, B, R;
if ( args->rho >= 1.0 )
kernel->width = (size_t)args->rho*2+1;
else if ( (type != DoGKernel) || (sigma >= sigma2) )
kernel->width = GetOptimalKernelWidth2D(args->rho,sigma);
else
kernel->width = GetOptimalKernelWidth2D(args->rho,sigma2);
kernel->height = kernel->width;
kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
/* WARNING: The following generates a 'sampled gaussian' kernel.
* What we really want is a 'discrete gaussian' kernel.
*
* How to do this is currently not known, but appears to be
* basied on the Error Function 'erf()' (intergral of a gaussian)
*/
if ( type == GaussianKernel || type == DoGKernel )
{ /* Calculate a Gaussian, OR positive half of a DoG */
if ( sigma > MagickEpsilon )
{ A = 1.0/(2.0*sigma*sigma); /* simplify loop expressions */
B = 1.0/(Magick2PI*sigma*sigma);
for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
kernel->values[i] = exp(-((double)(u*u+v*v))*A)*B;
}
else /* limiting case - a unity (normalized Dirac) kernel */
{ (void) ResetMagickMemory(kernel->values,0, (size_t)
kernel->width*kernel->height*sizeof(double));
kernel->values[kernel->x+kernel->y*kernel->width] = 1.0;
}
}
if ( type == DoGKernel )
{ /* Subtract a Negative Gaussian for "Difference of Gaussian" */
if ( sigma2 > MagickEpsilon )
{ sigma = sigma2; /* simplify loop expressions */
A = 1.0/(2.0*sigma*sigma);
B = 1.0/(Magick2PI*sigma*sigma);
for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
kernel->values[i] -= exp(-((double)(u*u+v*v))*A)*B;
}
else /* limiting case - a unity (normalized Dirac) kernel */
kernel->values[kernel->x+kernel->y*kernel->width] -= 1.0;
}
if ( type == LoGKernel )
{ /* Calculate a Laplacian of a Gaussian - Or Mexician Hat */
if ( sigma > MagickEpsilon )
{ A = 1.0/(2.0*sigma*sigma); /* simplify loop expressions */
B = 1.0/(MagickPI*sigma*sigma*sigma*sigma);
for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
{ R = ((double)(u*u+v*v))*A;
kernel->values[i] = (1-R)*exp(-R)*B;
}
}
else /* special case - generate a unity kernel */
{ (void) ResetMagickMemory(kernel->values,0, (size_t)
kernel->width*kernel->height*sizeof(double));
kernel->values[kernel->x+kernel->y*kernel->width] = 1.0;
}
}
/* Note the above kernels may have been 'clipped' by a user defined
** radius, producing a smaller (darker) kernel. Also for very small
** sigma's (> 0.1) the central value becomes larger than one, and thus
** producing a very bright kernel.
**
** Normalization will still be needed.
*/
/* Normalize the 2D Gaussian Kernel
**
** NB: a CorrelateNormalize performs a normal Normalize if
** there are no negative values.
*/
CalcKernelMetaData(kernel); /* the other kernel meta-data */
ScaleKernelInfo(kernel, 1.0, CorrelateNormalizeValue);
break;
}
case BlurKernel:
{ double
sigma = fabs(args->sigma),
alpha, beta;
if ( args->rho >= 1.0 )
kernel->width = (size_t)args->rho*2+1;
else
kernel->width = GetOptimalKernelWidth1D(args->rho,sigma);
kernel->height = 1;
kernel->x = (ssize_t) (kernel->width-1)/2;
kernel->y = 0;
kernel->negative_range = kernel->positive_range = 0.0;
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
#if 1
#define KernelRank 3
/* Formula derived from GetBlurKernel() in "effect.c" (plus bug fix).
** It generates a gaussian 3 times the width, and compresses it into
** the expected range. This produces a closer normalization of the
** resulting kernel, especially for very low sigma values.
** As such while wierd it is prefered.
**
** I am told this method originally came from Photoshop.
**
** A properly normalized curve is generated (apart from edge clipping)
** even though we later normalize the result (for edge clipping)
** to allow the correct generation of a "Difference of Blurs".
*/
/* initialize */
v = (ssize_t) (kernel->width*KernelRank-1)/2; /* start/end points to fit range */
(void) ResetMagickMemory(kernel->values,0, (size_t)
kernel->width*kernel->height*sizeof(double));
/* Calculate a Positive 1D Gaussian */
if ( sigma > MagickEpsilon )
{ sigma *= KernelRank; /* simplify loop expressions */
alpha = 1.0/(2.0*sigma*sigma);
beta= 1.0/(MagickSQ2PI*sigma );
for ( u=-v; u <= v; u++) {
kernel->values[(u+v)/KernelRank] +=
exp(-((double)(u*u))*alpha)*beta;
}
}
else /* special case - generate a unity kernel */
kernel->values[kernel->x+kernel->y*kernel->width] = 1.0;
#else
/* Direct calculation without curve averaging */
/* Calculate a Positive Gaussian */
if ( sigma > MagickEpsilon )
{ alpha = 1.0/(2.0*sigma*sigma); /* simplify loop expressions */
beta = 1.0/(MagickSQ2PI*sigma);
for ( i=0, u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
kernel->values[i] = exp(-((double)(u*u))*alpha)*beta;
}
else /* special case - generate a unity kernel */
{ (void) ResetMagickMemory(kernel->values,0, (size_t)
kernel->width*kernel->height*sizeof(double));
kernel->values[kernel->x+kernel->y*kernel->width] = 1.0;
}
#endif
/* Note the above kernel may have been 'clipped' by a user defined
** radius, producing a smaller (darker) kernel. Also for very small
** sigma's (> 0.1) the central value becomes larger than one, and thus
** producing a very bright kernel.
**
** Normalization will still be needed.
*/
/* Normalize the 1D Gaussian Kernel
**
** NB: a CorrelateNormalize performs a normal Normalize if
** there are no negative values.
*/
CalcKernelMetaData(kernel); /* the other kernel meta-data */
ScaleKernelInfo(kernel, 1.0, CorrelateNormalizeValue);
/* rotate the 1D kernel by given angle */
RotateKernelInfo(kernel, args->xi );
break;
}
case CometKernel:
{ double
sigma = fabs(args->sigma),
A;
if ( args->rho < 1.0 )
kernel->width = (GetOptimalKernelWidth1D(args->rho,sigma)-1)/2+1;
else
kernel->width = (size_t)args->rho;
kernel->x = kernel->y = 0;
kernel->height = 1;
kernel->negative_range = kernel->positive_range = 0.0;
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
/* A comet blur is half a 1D gaussian curve, so that the object is
** blurred in one direction only. This may not be quite the right
** curve to use so may change in the future. The function must be
** normalised after generation, which also resolves any clipping.
**
** As we are normalizing and not subtracting gaussians,
** there is no need for a divisor in the gaussian formula
**
** It is less comples
*/
if ( sigma > MagickEpsilon )
{
#if 1
#define KernelRank 3
v = (ssize_t) kernel->width*KernelRank; /* start/end points */
(void) ResetMagickMemory(kernel->values,0, (size_t)
kernel->width*sizeof(double));
sigma *= KernelRank; /* simplify the loop expression */
A = 1.0/(2.0*sigma*sigma);
/* B = 1.0/(MagickSQ2PI*sigma); */
for ( u=0; u < v; u++) {
kernel->values[u/KernelRank] +=
exp(-((double)(u*u))*A);
/* exp(-((double)(i*i))/2.0*sigma*sigma)/(MagickSQ2PI*sigma); */
}
for (i=0; i < (ssize_t) kernel->width; i++)
kernel->positive_range += kernel->values[i];
#else
A = 1.0/(2.0*sigma*sigma); /* simplify the loop expression */
/* B = 1.0/(MagickSQ2PI*sigma); */
for ( i=0; i < (ssize_t) kernel->width; i++)
kernel->positive_range +=
kernel->values[i] =
exp(-((double)(i*i))*A);
/* exp(-((double)(i*i))/2.0*sigma*sigma)/(MagickSQ2PI*sigma); */
#endif
}
else /* special case - generate a unity kernel */
{ (void) ResetMagickMemory(kernel->values,0, (size_t)
kernel->width*kernel->height*sizeof(double));
kernel->values[kernel->x+kernel->y*kernel->width] = 1.0;
kernel->positive_range = 1.0;
}
kernel->minimum = 0.0;
kernel->maximum = kernel->values[0];
kernel->negative_range = 0.0;
ScaleKernelInfo(kernel, 1.0, NormalizeValue); /* Normalize */
RotateKernelInfo(kernel, args->xi); /* Rotate by angle */
break;
}
/* Convolution Kernels - Well Known Constants */
case LaplacianKernel:
{ switch ( (int) args->rho ) {
case 0:
default: /* laplacian square filter -- default */
kernel=ParseKernelArray("3: -1,-1,-1 -1,8,-1 -1,-1,-1");
break;
case 1: /* laplacian diamond filter */
kernel=ParseKernelArray("3: 0,-1,0 -1,4,-1 0,-1,0");
break;
case 2:
kernel=ParseKernelArray("3: -2,1,-2 1,4,1 -2,1,-2");
break;
case 3:
kernel=ParseKernelArray("3: 1,-2,1 -2,4,-2 1,-2,1");
break;
case 5: /* a 5x5 laplacian */
kernel=ParseKernelArray(
"5: -4,-1,0,-1,-4 -1,2,3,2,-1 0,3,4,3,0 -1,2,3,2,-1 -4,-1,0,-1,-4");
break;
case 7: /* a 7x7 laplacian */
kernel=ParseKernelArray(
"7:-10,-5,-2,-1,-2,-5,-10 -5,0,3,4,3,0,-5 -2,3,6,7,6,3,-2 -1,4,7,8,7,4,-1 -2,3,6,7,6,3,-2 -5,0,3,4,3,0,-5 -10,-5,-2,-1,-2,-5,-10" );
break;
case 15: /* a 5x5 LoG (sigma approx 1.4) */
kernel=ParseKernelArray(
"5: 0,0,-1,0,0 0,-1,-2,-1,0 -1,-2,16,-2,-1 0,-1,-2,-1,0 0,0,-1,0,0");
break;
case 19: /* a 9x9 LoG (sigma approx 1.4) */
/* http://www.cscjournals.org/csc/manuscript/Journals/IJIP/volume3/Issue1/IJIP-15.pdf */
kernel=ParseKernelArray(
"9: 0,-1,-1,-2,-2,-2,-1,-1,0 -1,-2,-4,-5,-5,-5,-4,-2,-1 -1,-4,-5,-3,-0,-3,-5,-4,-1 -2,-5,-3,12,24,12,-3,-5,-2 -2,-5,-0,24,40,24,-0,-5,-2 -2,-5,-3,12,24,12,-3,-5,-2 -1,-4,-5,-3,-0,-3,-5,-4,-1 -1,-2,-4,-5,-5,-5,-4,-2,-1 0,-1,-1,-2,-2,-2,-1,-1,0");
break;
}
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
break;
}
case SobelKernel:
#if 0
{ /* Sobel with optional 'sub-types' */
switch ( (int) args->rho ) {
default:
case 0:
kernel=ParseKernelArray("3: 1,0,-1 2,0,-2 1,0,-1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
break;
case 1:
kernel=ParseKernelArray("3: 1,0,-1 2,0,-2 1,0,-1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ScaleKernelInfo(kernel, 0.25, NoValue);
break;
case 2:
kernel=ParseKernelArray("3: 1,2,0 2,0,-2 0,-2,-1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ScaleKernelInfo(kernel, 0.25, NoValue);
break;
}
if ( fabs(args->sigma) > MagickEpsilon )
/* Rotate by correctly supplied 'angle' */
RotateKernelInfo(kernel, args->sigma);
else if ( args->rho > 30.0 || args->rho < -30.0 )
/* Rotate by out of bounds 'type' */
RotateKernelInfo(kernel, args->rho);
break;
}
#else
{ /* Simple Sobel Kernel */
kernel=ParseKernelArray("3: 1,0,-1 2,0,-2 1,0,-1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->rho);
break;
}
#endif
case RobertsKernel:
{
kernel=ParseKernelArray("3: 0,0,0 1,-1,0 0,0,0");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->rho);
break;
}
case PrewittKernel:
{
kernel=ParseKernelArray("3: 1,0,-1 1,0,-1 1,0,-1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->rho);
break;
}
case CompassKernel:
{
kernel=ParseKernelArray("3: 1,1,-1 1,-2,-1 1,1,-1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->rho);
break;
}
case KirschKernel:
{
kernel=ParseKernelArray("3: 5,-3,-3 5,0,-3 5,-3,-3");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->rho);
break;
}
case FreiChenKernel:
/* Direction is set to be left to right positive */
/* http://www.math.tau.ac.il/~turkel/notes/edge_detectors.pdf -- RIGHT? */
/* http://ltswww.epfl.ch/~courstiv/exos_labos/sol3.pdf -- WRONG? */
{ switch ( (int) args->rho ) {
default:
case 0:
kernel=ParseKernelArray("3: 1,0,-1 2,0,-2 1,0,-1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
kernel->values[3] = +MagickSQ2;
kernel->values[5] = -MagickSQ2;
CalcKernelMetaData(kernel); /* recalculate meta-data */
break;
case 2:
kernel=ParseKernelArray("3: 1,2,0 2,0,-2 0,-2,-1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
kernel->values[1] = kernel->values[3] = +MagickSQ2;
kernel->values[5] = kernel->values[7] = -MagickSQ2;
CalcKernelMetaData(kernel); /* recalculate meta-data */
ScaleKernelInfo(kernel, 1.0/2.0*MagickSQ2, NoValue);
break;
case 10:
kernel=AcquireKernelInfo("FreiChen:11;FreiChen:12;FreiChen:13;FreiChen:14;FreiChen:15;FreiChen:16;FreiChen:17;FreiChen:18;FreiChen:19");
if (kernel == (KernelInfo *) NULL)
return(kernel);
break;
case 1:
case 11:
kernel=ParseKernelArray("3: 1,0,-1 2,0,-2 1,0,-1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
kernel->values[3] = +MagickSQ2;
kernel->values[5] = -MagickSQ2;
CalcKernelMetaData(kernel); /* recalculate meta-data */
ScaleKernelInfo(kernel, 1.0/2.0*MagickSQ2, NoValue);
break;
case 12:
kernel=ParseKernelArray("3: 1,2,1 0,0,0 1,2,1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
kernel->values[1] = +MagickSQ2;
kernel->values[7] = +MagickSQ2;
CalcKernelMetaData(kernel);
ScaleKernelInfo(kernel, 1.0/2.0*MagickSQ2, NoValue);
break;
case 13:
kernel=ParseKernelArray("3: 2,-1,0 -1,0,1 0,1,-2");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
kernel->values[0] = +MagickSQ2;
kernel->values[8] = -MagickSQ2;
CalcKernelMetaData(kernel);
ScaleKernelInfo(kernel, 1.0/2.0*MagickSQ2, NoValue);
break;
case 14:
kernel=ParseKernelArray("3: 0,1,-2 -1,0,1 2,-1,0");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
kernel->values[2] = -MagickSQ2;
kernel->values[6] = +MagickSQ2;
CalcKernelMetaData(kernel);
ScaleKernelInfo(kernel, 1.0/2.0*MagickSQ2, NoValue);
break;
case 15:
kernel=ParseKernelArray("3: 0,-1,0 1,0,1 0,-1,0");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ScaleKernelInfo(kernel, 1.0/2.0, NoValue);
break;
case 16:
kernel=ParseKernelArray("3: 1,0,-1 0,0,0 -1,0,1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ScaleKernelInfo(kernel, 1.0/2.0, NoValue);
break;
case 17:
kernel=ParseKernelArray("3: 1,-2,1 -2,4,-2 -1,-2,1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ScaleKernelInfo(kernel, 1.0/6.0, NoValue);
break;
case 18:
kernel=ParseKernelArray("3: -2,1,-2 1,4,1 -2,1,-2");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ScaleKernelInfo(kernel, 1.0/6.0, NoValue);
break;
case 19:
kernel=ParseKernelArray("3: 1,1,1 1,1,1 1,1,1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ScaleKernelInfo(kernel, 1.0/3.0, NoValue);
break;
}
if ( fabs(args->sigma) > MagickEpsilon )
/* Rotate by correctly supplied 'angle' */
RotateKernelInfo(kernel, args->sigma);
else if ( args->rho > 30.0 || args->rho < -30.0 )
/* Rotate by out of bounds 'type' */
RotateKernelInfo(kernel, args->rho);
break;
}
/* Boolean Kernels */
case DiamondKernel:
{
if (args->rho < 1.0)
kernel->width = kernel->height = 3; /* default radius = 1 */
else
kernel->width = kernel->height = ((size_t)args->rho)*2+1;
kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
/* set all kernel values within diamond area to scale given */
for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
if ( (labs((long) u)+labs((long) v)) <= (long) kernel->x)
kernel->positive_range += kernel->values[i] = args->sigma;
else
kernel->values[i] = nan;
kernel->minimum = kernel->maximum = args->sigma; /* a flat shape */
break;
}
case SquareKernel:
case RectangleKernel:
{ double
scale;
if ( type == SquareKernel )
{
if (args->rho < 1.0)
kernel->width = kernel->height = 3; /* default radius = 1 */
else
kernel->width = kernel->height = (size_t) (2*args->rho+1);
kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
scale = args->sigma;
}
else {
/* NOTE: user defaults set in "AcquireKernelInfo()" */
if ( args->rho < 1.0 || args->sigma < 1.0 )
return(DestroyKernelInfo(kernel)); /* invalid args given */
kernel->width = (size_t)args->rho;
kernel->height = (size_t)args->sigma;
if ( args->xi < 0.0 || args->xi > (double)kernel->width ||
args->psi < 0.0 || args->psi > (double)kernel->height )
return(DestroyKernelInfo(kernel)); /* invalid args given */
kernel->x = (ssize_t) args->xi;
kernel->y = (ssize_t) args->psi;
scale = 1.0;
}
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
/* set all kernel values to scale given */
u=(ssize_t) (kernel->width*kernel->height);
for ( i=0; i < u; i++)
kernel->values[i] = scale;
kernel->minimum = kernel->maximum = scale; /* a flat shape */
kernel->positive_range = scale*u;
break;
}
case DiskKernel:
{
ssize_t
limit = (ssize_t)(args->rho*args->rho);
if (args->rho < 0.4) /* default radius approx 3.5 */
kernel->width = kernel->height = 7L, limit = 10L;
else
kernel->width = kernel->height = (size_t)fabs(args->rho)*2+1;
kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
/* set all kernel values within disk area to scale given */
for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
if ((u*u+v*v) <= limit)
kernel->positive_range += kernel->values[i] = args->sigma;
else
kernel->values[i] = nan;
kernel->minimum = kernel->maximum = args->sigma; /* a flat shape */
break;
}
case PlusKernel:
{
if (args->rho < 1.0)
kernel->width = kernel->height = 5; /* default radius 2 */
else
kernel->width = kernel->height = ((size_t)args->rho)*2+1;
kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
/* set all kernel values along axises to given scale */
for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
kernel->values[i] = (u == 0 || v == 0) ? args->sigma : nan;
kernel->minimum = kernel->maximum = args->sigma; /* a flat shape */
kernel->positive_range = args->sigma*(kernel->width*2.0 - 1.0);
break;
}
case CrossKernel:
{
if (args->rho < 1.0)
kernel->width = kernel->height = 5; /* default radius 2 */
else
kernel->width = kernel->height = ((size_t)args->rho)*2+1;
kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
/* set all kernel values along axises to given scale */
for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
kernel->values[i] = (u == v || u == -v) ? args->sigma : nan;
kernel->minimum = kernel->maximum = args->sigma; /* a flat shape */
kernel->positive_range = args->sigma*(kernel->width*2.0 - 1.0);
break;
}
/* HitAndMiss Kernels */
case RingKernel:
case PeaksKernel:
{
ssize_t
limit1,
limit2,
scale;
if (args->rho < args->sigma)
{
kernel->width = ((size_t)args->sigma)*2+1;
limit1 = (ssize_t)(args->rho*args->rho);
limit2 = (ssize_t)(args->sigma*args->sigma);
}
else
{
kernel->width = ((size_t)args->rho)*2+1;
limit1 = (ssize_t)(args->sigma*args->sigma);
limit2 = (ssize_t)(args->rho*args->rho);
}
if ( limit2 <= 0 )
kernel->width = 7L, limit1 = 7L, limit2 = 11L;
kernel->height = kernel->width;
kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
/* set a ring of points of 'scale' ( 0.0 for PeaksKernel ) */
scale = (ssize_t) (( type == PeaksKernel) ? 0.0 : args->xi);
for ( i=0, v= -kernel->y; v <= (ssize_t)kernel->y; v++)
for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
{ ssize_t radius=u*u+v*v;
if (limit1 < radius && radius <= limit2)
kernel->positive_range += kernel->values[i] = (double) scale;
else
kernel->values[i] = nan;
}
kernel->minimum = kernel->maximum = (double) scale;
if ( type == PeaksKernel ) {
/* set the central point in the middle */
kernel->values[kernel->x+kernel->y*kernel->width] = 1.0;
kernel->positive_range = 1.0;
kernel->maximum = 1.0;
}
break;
}
case EdgesKernel:
{
kernel=ParseKernelArray("3: 0,0,0 -,1,- 1,1,1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ExpandMirrorKernelInfo(kernel); /* mirror expansion of other kernels */
break;
}
case CornersKernel:
{
kernel=ParseKernelArray("3: 0,0,- 0,1,1 -,1,-");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ExpandRotateKernelInfo(kernel, 90.0); /* Expand 90 degree rotations */
break;
}
case ThinDiagonalsKernel:
{
switch ( (int) args->rho ) {
case 0:
default:
{ KernelInfo
*new_kernel;
kernel=ParseKernelArray("3: 0,0,0 0,1,1 1,1,-");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
new_kernel=ParseKernelArray("3: 0,0,1 0,1,1 0,1,-");
if (new_kernel == (KernelInfo *) NULL)
return(DestroyKernelInfo(kernel));
new_kernel->type = type;
LastKernelInfo(kernel)->next = new_kernel;
ExpandMirrorKernelInfo(kernel);
break;
}
case 1:
kernel=ParseKernelArray("3: 0,0,0 0,1,1 1,1,-");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->sigma);
break;
case 2:
kernel=ParseKernelArray("3: 0,0,1 0,1,1 0,1,-");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->sigma);
break;
}
break;
}
case LineEndsKernel:
{ /* Kernels for finding the end of thin lines */
switch ( (int) args->rho ) {
case 0:
default:
/* set of kernels to find all end of lines */
kernel=AcquireKernelInfo("LineEnds:1>;LineEnds:2>");
if (kernel == (KernelInfo *) NULL)
return(kernel);
break;
case 1:
/* kernel for 4-connected line ends - no rotation */
kernel=ParseKernelArray("3: 0,0,- 0,1,1 0,0,-");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->sigma);
break;
case 2:
/* kernel to add for 8-connected lines - no rotation */
kernel=ParseKernelArray("3: 0,0,0 0,1,0 0,0,1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->sigma);
break;
case 3:
/* kernel to add for orthogonal line ends - does not find corners */
kernel=ParseKernelArray("3: 0,0,0 0,1,1 0,0,0");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->sigma);
break;
case 4:
/* traditional line end - fails on last T end */
kernel=ParseKernelArray("3: 0,0,0 0,1,- 0,0,-");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->sigma);
break;
}
break;
}
case LineJunctionsKernel:
{ /* kernels for finding the junctions of multiple lines */
switch ( (int) args->rho ) {
case 0:
default:
/* set of kernels to find all line junctions */
kernel=AcquireKernelInfo("LineJunctions:1@;LineJunctions:2>");
if (kernel == (KernelInfo *) NULL)
return(kernel);
break;
case 1:
/* Y Junction */
kernel=ParseKernelArray("3: 1,-,1 -,1,- -,1,-");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->sigma);
break;
case 2:
/* Diagonal T Junctions */
kernel=ParseKernelArray("3: 1,-,- -,1,- 1,-,1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->sigma);
break;
case 3:
/* Orthogonal T Junctions */
kernel=ParseKernelArray("3: -,-,- 1,1,1 -,1,-");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->sigma);
break;
case 4:
/* Diagonal X Junctions */
kernel=ParseKernelArray("3: 1,-,1 -,1,- 1,-,1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->sigma);
break;
case 5:
/* Orthogonal X Junctions - minimal diamond kernel */
kernel=ParseKernelArray("3: -,1,- 1,1,1 -,1,-");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
RotateKernelInfo(kernel, args->sigma);
break;
}
break;
}
case RidgesKernel:
{ /* Ridges - Ridge finding kernels */
KernelInfo
*new_kernel;
switch ( (int) args->rho ) {
case 1:
default:
kernel=ParseKernelArray("3x1:0,1,0");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ExpandRotateKernelInfo(kernel, 90.0); /* 2 rotated kernels (symmetrical) */
break;
case 2:
kernel=ParseKernelArray("4x1:0,1,1,0");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ExpandRotateKernelInfo(kernel, 90.0); /* 4 rotated kernels */
/* Kernels to find a stepped 'thick' line, 4 rotates + mirrors */
/* Unfortunatally we can not yet rotate a non-square kernel */
/* But then we can't flip a non-symetrical kernel either */
new_kernel=ParseKernelArray("4x3+1+1:0,1,1,- -,1,1,- -,1,1,0");
if (new_kernel == (KernelInfo *) NULL)
return(DestroyKernelInfo(kernel));
new_kernel->type = type;
LastKernelInfo(kernel)->next = new_kernel;
new_kernel=ParseKernelArray("4x3+2+1:0,1,1,- -,1,1,- -,1,1,0");
if (new_kernel == (KernelInfo *) NULL)
return(DestroyKernelInfo(kernel));
new_kernel->type = type;
LastKernelInfo(kernel)->next = new_kernel;
new_kernel=ParseKernelArray("4x3+1+1:-,1,1,0 -,1,1,- 0,1,1,-");
if (new_kernel == (KernelInfo *) NULL)
return(DestroyKernelInfo(kernel));
new_kernel->type = type;
LastKernelInfo(kernel)->next = new_kernel;
new_kernel=ParseKernelArray("4x3+2+1:-,1,1,0 -,1,1,- 0,1,1,-");
if (new_kernel == (KernelInfo *) NULL)
return(DestroyKernelInfo(kernel));
new_kernel->type = type;
LastKernelInfo(kernel)->next = new_kernel;
new_kernel=ParseKernelArray("3x4+1+1:0,-,- 1,1,1 1,1,1 -,-,0");
if (new_kernel == (KernelInfo *) NULL)
return(DestroyKernelInfo(kernel));
new_kernel->type = type;
LastKernelInfo(kernel)->next = new_kernel;
new_kernel=ParseKernelArray("3x4+1+2:0,-,- 1,1,1 1,1,1 -,-,0");
if (new_kernel == (KernelInfo *) NULL)
return(DestroyKernelInfo(kernel));
new_kernel->type = type;
LastKernelInfo(kernel)->next = new_kernel;
new_kernel=ParseKernelArray("3x4+1+1:-,-,0 1,1,1 1,1,1 0,-,-");
if (new_kernel == (KernelInfo *) NULL)
return(DestroyKernelInfo(kernel));
new_kernel->type = type;
LastKernelInfo(kernel)->next = new_kernel;
new_kernel=ParseKernelArray("3x4+1+2:-,-,0 1,1,1 1,1,1 0,-,-");
if (new_kernel == (KernelInfo *) NULL)
return(DestroyKernelInfo(kernel));
new_kernel->type = type;
LastKernelInfo(kernel)->next = new_kernel;
break;
}
break;
}
case ConvexHullKernel:
{
KernelInfo
*new_kernel;
/* first set of 8 kernels */
kernel=ParseKernelArray("3: 1,1,- 1,0,- 1,-,0");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ExpandRotateKernelInfo(kernel, 90.0);
/* append the mirror versions too - no flip function yet */
new_kernel=ParseKernelArray("3: 1,1,1 1,0,- -,-,0");
if (new_kernel == (KernelInfo *) NULL)
return(DestroyKernelInfo(kernel));
new_kernel->type = type;
ExpandRotateKernelInfo(new_kernel, 90.0);
LastKernelInfo(kernel)->next = new_kernel;
break;
}
case SkeletonKernel:
{
KernelInfo
*new_kernel;
switch ( (int) args->rho ) {
case 1:
default:
/* Traditional Skeleton...
** A cyclically rotated single kernel
*/
kernel=ParseKernelArray("3: 0,0,0 -,1,- 1,1,1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
ExpandRotateKernelInfo(kernel, 45.0); /* 8 rotations */
break;
case 2:
/* HIPR Variation of the cyclic skeleton
** Corners of the traditional method made more forgiving,
** but the retain the same cyclic order.
*/
kernel=ParseKernelArray("3: 0,0,0 -,1,- 1,1,1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = type;
new_kernel=ParseKernelArray("3: -,0,0 1,1,0 -,1,-");
if (new_kernel == (KernelInfo *) NULL)
return(new_kernel);
new_kernel->type = type;
LastKernelInfo(kernel)->next = new_kernel;
ExpandRotateKernelInfo(kernel, 90.0); /* 4 rotations of the 2 kernels */
break;
}
break;
}
/* Distance Measuring Kernels */
case ChebyshevKernel:
{
if (args->rho < 1.0)
kernel->width = kernel->height = 3; /* default radius = 1 */
else
kernel->width = kernel->height = ((size_t)args->rho)*2+1;
kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
kernel->positive_range += ( kernel->values[i] =
args->sigma*((labs((long) u)>labs((long) v)) ? labs((long) u) : labs((long) v)) );
kernel->maximum = kernel->values[0];
break;
}
case ManhattanKernel:
{
if (args->rho < 1.0)
kernel->width = kernel->height = 3; /* default radius = 1 */
else
kernel->width = kernel->height = ((size_t)args->rho)*2+1;
kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
kernel->positive_range += ( kernel->values[i] =
args->sigma*(labs((long) u)+labs((long) v)) );
kernel->maximum = kernel->values[0];
break;
}
case EuclideanKernel:
{
if (args->rho < 1.0)
kernel->width = kernel->height = 3; /* default radius = 1 */
else
kernel->width = kernel->height = ((size_t)args->rho)*2+1;
kernel->x = kernel->y = (ssize_t) (kernel->width-1)/2;
kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (kernel->values == (double *) NULL)
return(DestroyKernelInfo(kernel));
for ( i=0, v=-kernel->y; v <= (ssize_t)kernel->y; v++)
for ( u=-kernel->x; u <= (ssize_t)kernel->x; u++, i++)
kernel->positive_range += ( kernel->values[i] =
args->sigma*sqrt((double)(u*u+v*v)) );
kernel->maximum = kernel->values[0];
break;
}
case UnityKernel:
default:
{
/* Unity or No-Op Kernel - Basically just a single pixel on its own */
kernel=ParseKernelArray("1:1");
if (kernel == (KernelInfo *) NULL)
return(kernel);
kernel->type = ( type == UnityKernel ) ? UnityKernel : UndefinedKernel;
break;
}
break;
}
return(kernel);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% C l o n e K e r n e l I n f o %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% CloneKernelInfo() creates a new clone of the given Kernel List so that its
% can be modified without effecting the original. The cloned kernel should
% be destroyed using DestoryKernelInfo() when no longer needed.
%
% The format of the CloneKernelInfo method is:
%
% KernelInfo *CloneKernelInfo(const KernelInfo *kernel)
%
% A description of each parameter follows:
%
% o kernel: the Morphology/Convolution kernel to be cloned
%
*/
MagickExport KernelInfo *CloneKernelInfo(const KernelInfo *kernel)
{
register ssize_t
i;
KernelInfo
*new_kernel;
assert(kernel != (KernelInfo *) NULL);
new_kernel=(KernelInfo *) AcquireMagickMemory(sizeof(*kernel));
if (new_kernel == (KernelInfo *) NULL)
return(new_kernel);
*new_kernel=(*kernel); /* copy values in structure */
/* replace the values with a copy of the values */
new_kernel->values=(double *) AcquireQuantumMemory(kernel->width,
kernel->height*sizeof(double));
if (new_kernel->values == (double *) NULL)
return(DestroyKernelInfo(new_kernel));
for (i=0; i < (ssize_t) (kernel->width*kernel->height); i++)
new_kernel->values[i]=kernel->values[i];
/* Also clone the next kernel in the kernel list */
if ( kernel->next != (KernelInfo *) NULL ) {
new_kernel->next = CloneKernelInfo(kernel->next);
if ( new_kernel->next == (KernelInfo *) NULL )
return(DestroyKernelInfo(new_kernel));
}
return(new_kernel);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% D e s t r o y K e r n e l I n f o %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% DestroyKernelInfo() frees the memory used by a Convolution/Morphology
% kernel.
%
% The format of the DestroyKernelInfo method is:
%
% KernelInfo *DestroyKernelInfo(KernelInfo *kernel)
%
% A description of each parameter follows:
%
% o kernel: the Morphology/Convolution kernel to be destroyed
%
*/
MagickExport KernelInfo *DestroyKernelInfo(KernelInfo *kernel)
{
assert(kernel != (KernelInfo *) NULL);
if ( kernel->next != (KernelInfo *) NULL )
kernel->next = DestroyKernelInfo(kernel->next);
kernel->values = (double *)RelinquishMagickMemory(kernel->values);
kernel = (KernelInfo *) RelinquishMagickMemory(kernel);
return(kernel);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
+ E x p a n d M i r r o r K e r n e l I n f o %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ExpandMirrorKernelInfo() takes a single kernel, and expands it into a
% sequence of 90-degree rotated kernels but providing a reflected 180
% rotatation, before the -/+ 90-degree rotations.
%
% This special rotation order produces a better, more symetrical thinning of
% objects.
%
% The format of the ExpandMirrorKernelInfo method is:
%
% void ExpandMirrorKernelInfo(KernelInfo *kernel)
%
% A description of each parameter follows:
%
% o kernel: the Morphology/Convolution kernel
%
% This function is only internel to this module, as it is not finalized,
% especially with regard to non-orthogonal angles, and rotation of larger
% 2D kernels.
*/
#if 0
static void FlopKernelInfo(KernelInfo *kernel)
{ /* Do a Flop by reversing each row. */
size_t
y;
register ssize_t
x,r;
register double
*k,t;
for ( y=0, k=kernel->values; y < kernel->height; y++, k+=kernel->width)
for ( x=0, r=kernel->width-1; x<kernel->width/2; x++, r--)
t=k[x], k[x]=k[r], k[r]=t;
kernel->x = kernel->width - kernel->x - 1;
angle = fmod(angle+180.0, 360.0);
}
#endif
static void ExpandMirrorKernelInfo(KernelInfo *kernel)
{
KernelInfo
*clone,
*last;
last = kernel;
clone = CloneKernelInfo(last);
RotateKernelInfo(clone, 180); /* flip */
LastKernelInfo(last)->next = clone;
last = clone;
clone = CloneKernelInfo(last);
RotateKernelInfo(clone, 90); /* transpose */
LastKernelInfo(last)->next = clone;
last = clone;
clone = CloneKernelInfo(last);
RotateKernelInfo(clone, 180); /* flop */
LastKernelInfo(last)->next = clone;
return;
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
+ E x p a n d R o t a t e K e r n e l I n f o %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ExpandRotateKernelInfo() takes a kernel list, and expands it by rotating
% incrementally by the angle given, until the first kernel repeats.
%
% WARNING: 45 degree rotations only works for 3x3 kernels.
% While 90 degree roatations only works for linear and square kernels
%
% The format of the ExpandRotateKernelInfo method is:
%
% void ExpandRotateKernelInfo(KernelInfo *kernel, double angle)
%
% A description of each parameter follows:
%
% o kernel: the Morphology/Convolution kernel
%
% o angle: angle to rotate in degrees
%
% This function is only internel to this module, as it is not finalized,
% especially with regard to non-orthogonal angles, and rotation of larger
% 2D kernels.
*/
/* Internal Routine - Return true if two kernels are the same */
static MagickBooleanType SameKernelInfo(const KernelInfo *kernel1,
const KernelInfo *kernel2)
{
register size_t
i;
/* check size and origin location */
if ( kernel1->width != kernel2->width
|| kernel1->height != kernel2->height
|| kernel1->x != kernel2->x
|| kernel1->y != kernel2->y )
return MagickFalse;
/* check actual kernel values */
for (i=0; i < (kernel1->width*kernel1->height); i++) {
/* Test for Nan equivelence */
if ( IsNan(kernel1->values[i]) && !IsNan(kernel2->values[i]) )
return MagickFalse;
if ( IsNan(kernel2->values[i]) && !IsNan(kernel1->values[i]) )
return MagickFalse;
/* Test actual values are equivelent */
if ( fabs(kernel1->values[i] - kernel2->values[i]) > MagickEpsilon )
return MagickFalse;
}
return MagickTrue;
}
static void ExpandRotateKernelInfo(KernelInfo *kernel, const double angle)
{
KernelInfo
*clone,
*last;
last = kernel;
while(1) {
clone = CloneKernelInfo(last);
RotateKernelInfo(clone, angle);
if ( SameKernelInfo(kernel, clone) == MagickTrue )
break;
LastKernelInfo(last)->next = clone;
last = clone;
}
clone = DestroyKernelInfo(clone); /* kernel has repeated - junk the clone */
return;
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
+ C a l c M e t a K e r n a l I n f o %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% CalcKernelMetaData() recalculate the KernelInfo meta-data of this kernel only,
% using the kernel values. This should only ne used if it is not posible to
% calculate that meta-data in some easier way.
%
% It is important that the meta-data is correct before ScaleKernelInfo() is
% used to perform kernel normalization.
%
% The format of the CalcKernelMetaData method is:
%
% void CalcKernelMetaData(KernelInfo *kernel, const double scale )
%
% A description of each parameter follows:
%
% o kernel: the Morphology/Convolution kernel to modify
%
% WARNING: Minimum and Maximum values are assumed to include zero, even if
% zero is not part of the kernel (as in Gaussian Derived kernels). This
% however is not true for flat-shaped morphological kernels.
%
% WARNING: Only the specific kernel pointed to is modified, not a list of
% multiple kernels.
%
% This is an internal function and not expected to be useful outside this
% module. This could change however.
*/
static void CalcKernelMetaData(KernelInfo *kernel)
{
register size_t
i;
kernel->minimum = kernel->maximum = 0.0;
kernel->negative_range = kernel->positive_range = 0.0;
for (i=0; i < (kernel->width*kernel->height); i++)
{
if ( fabs(kernel->values[i]) < MagickEpsilon )
kernel->values[i] = 0.0;
( kernel->values[i] < 0)
? ( kernel->negative_range += kernel->values[i] )
: ( kernel->positive_range += kernel->values[i] );
Minimize(kernel->minimum, kernel->values[i]);
Maximize(kernel->maximum, kernel->values[i]);
}
return;
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% M o r p h o l o g y A p p l y %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% MorphologyApply() applies a morphological method, multiple times using
% a list of multiple kernels.
%
% It is basically equivelent to as MorphologyImageChannel() (see below) but
% without any user controls. This allows internel programs to use this
% function, to actually perform a specific task without posible interference
% by any API user supplied settings.
%
% It is MorphologyImageChannel() task to extract any such user controls, and
% pass them to this function for processing.
%
% More specifically kernels are not normalized/scaled/blended by the
% 'convolve:scale' Image Artifact (setting), nor is the convolve bias
% (-bias setting or image->bias) loooked at, but must be supplied from the
% function arguments.
%
% The format of the MorphologyApply method is:
%
% Image *MorphologyApply(const Image *image,MorphologyMethod method,
% const ssize_t iterations,const KernelInfo *kernel,
% const CompositeMethod compose, const double bias,
% ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the source image
%
% o method: the morphology method to be applied.
%
% o iterations: apply the operation this many times (or no change).
% A value of -1 means loop until no change found.
% How this is applied may depend on the morphology method.
% Typically this is a value of 1.
%
% o channel: the channel type.
%
% o kernel: An array of double representing the morphology kernel.
%
% o compose: How to handle or merge multi-kernel results.
% If 'UndefinedCompositeOp' use default for the Morphology method.
% If 'NoCompositeOp' force image to be re-iterated by each kernel.
% Otherwise merge the results using the compose method given.
%
% o bias: Convolution Output Bias.
%
% o exception: return any errors or warnings in this structure.
%
*/
/* Apply a Morphology Primative to an image using the given kernel.
** Two pre-created images must be provided, no image is created.
** It returns the number of pixels that changed betwene the images
** for convergence determination.
*/
static size_t MorphologyPrimitive(const Image *image, Image
*result_image, const MorphologyMethod method, const ChannelType channel,
const KernelInfo *kernel,const double bias,ExceptionInfo *exception)
{
#define MorphologyTag "Morphology/Image"
CacheView
*p_view,
*q_view;
ssize_t
y, offx, offy,
changed;
MagickBooleanType
status;
MagickOffsetType
progress;
assert(image != (Image *) NULL);
assert(image->signature == MagickSignature);
assert(result_image != (Image *) NULL);
assert(result_image->signature == MagickSignature);
assert(kernel != (KernelInfo *) NULL);
assert(kernel->signature == MagickSignature);
assert(exception != (ExceptionInfo *) NULL);
assert(exception->signature == MagickSignature);
status=MagickTrue;
changed=0;
progress=0;
p_view=AcquireCacheView(image);
q_view=AcquireCacheView(result_image);
/* Some methods (including convolve) needs use a reflected kernel.
* Adjust 'origin' offsets to loop though kernel as a reflection.
*/
offx = kernel->x;
offy = kernel->y;
switch(method) {
case ConvolveMorphology:
case DilateMorphology:
case DilateIntensityMorphology:
case DistanceMorphology:
/* kernel needs to used with reflection about origin */
offx = (ssize_t) kernel->width-offx-1;
offy = (ssize_t) kernel->height-offy-1;
break;
case ErodeMorphology:
case ErodeIntensityMorphology:
case HitAndMissMorphology:
case ThinningMorphology:
case ThickenMorphology:
/* kernel is used as is, without reflection */
break;
default:
assert("Not a Primitive Morphology Method" != (char *) NULL);
break;
}
if ( method == ConvolveMorphology && kernel->width == 1 )
{ /* Special handling (for speed) of vertical (blur) kernels.
** This performs its handling in columns rather than in rows.
** This is only done fo convolve as it is the only method that
** generates very large 1-D vertical kernels (such as a 'BlurKernel')
**
** Timing tests (on single CPU laptop)
** Using a vertical 1-d Blue with normal row-by-row (below)
** time convert logo: -morphology Convolve Blur:0x10+90 null:
** 0.807u
** Using this column method
** time convert logo: -morphology Convolve Blur:0x10+90 null:
** 0.620u
**
** Anthony Thyssen, 14 June 2010
*/
register ssize_t
x;
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
for (x=0; x < (ssize_t) image->columns; x++)
{
register const PixelPacket
*restrict p;
register const IndexPacket
*restrict p_indexes;
register PixelPacket
*restrict q;
register IndexPacket
*restrict q_indexes;
register ssize_t
y;
size_t
r;
if (status == MagickFalse)
continue;
p=GetCacheViewVirtualPixels(p_view, x, -offy,1,
image->rows+kernel->height, exception);
q=GetCacheViewAuthenticPixels(q_view,x,0,1,result_image->rows,exception);
if ((p == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
{
status=MagickFalse;
continue;
}
p_indexes=GetCacheViewVirtualIndexQueue(p_view);
q_indexes=GetCacheViewAuthenticIndexQueue(q_view);
r = offy; /* offset to the origin pixel in 'p' */
for (y=0; y < (ssize_t) image->rows; y++)
{
register ssize_t
v;
register const double
*restrict k;
register const PixelPacket
*restrict k_pixels;
register const IndexPacket
*restrict k_indexes;
MagickPixelPacket
result;
/* Copy input image to the output image for unused channels
* This removes need for 'cloning' a new image every iteration
*/
*q = p[r];
if (image->colorspace == CMYKColorspace)
q_indexes[y] = p_indexes[r];
/* Set the bias of the weighted average output */
result.red =
result.green =
result.blue =
result.opacity =
result.index = bias;
/* Weighted Average of pixels using reflected kernel
**
** NOTE for correct working of this operation for asymetrical
** kernels, the kernel needs to be applied in its reflected form.
** That is its values needs to be reversed.
*/
k = &kernel->values[ kernel->height-1 ];
k_pixels = p;
k_indexes = p_indexes;
if ( ((channel & SyncChannels) == 0 ) ||
(image->matte == MagickFalse) )
{ /* No 'Sync' involved.
** Convolution is simple greyscale channel operation
*/
for (v=0; v < (ssize_t) kernel->height; v++) {
if ( IsNan(*k) ) continue;
result.red += (*k)*k_pixels->red;
result.green += (*k)*k_pixels->green;
result.blue += (*k)*k_pixels->blue;
result.opacity += (*k)*k_pixels->opacity;
if ( image->colorspace == CMYKColorspace)
result.index += (*k)*(*k_indexes);
k--;
k_pixels++;
k_indexes++;
}
if ((channel & RedChannel) != 0)
q->red = ClampToQuantum(result.red);
if ((channel & GreenChannel) != 0)
q->green = ClampToQuantum(result.green);
if ((channel & BlueChannel) != 0)
q->blue = ClampToQuantum(result.blue);
if ((channel & OpacityChannel) != 0
&& image->matte == MagickTrue )
q->opacity = ClampToQuantum(result.opacity);
if ((channel & IndexChannel) != 0
&& image->colorspace == CMYKColorspace)
q_indexes[x] = ClampToQuantum(result.index);
}
else
{ /* Channel 'Sync' Flag, and Alpha Channel enabled.
** Weight the color channels with Alpha Channel so that
** transparent pixels are not part of the results.
*/
MagickRealType
alpha, /* alpha weighting of colors : kernel*alpha */
gamma; /* divisor, sum of color weighting values */
gamma=0.0;
for (v=0; v < (ssize_t) kernel->height; v++) {
if ( IsNan(*k) ) continue;
alpha=(*k)*(QuantumScale*(QuantumRange-k_pixels->opacity));
gamma += alpha;
result.red += alpha*k_pixels->red;
result.green += alpha*k_pixels->green;
result.blue += alpha*k_pixels->blue;
result.opacity += (*k)*k_pixels->opacity;
if ( image->colorspace == CMYKColorspace)
result.index += alpha*(*k_indexes);
k--;
k_pixels++;
k_indexes++;
}
/* Sync'ed channels, all channels are modified */
gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
q->red = ClampToQuantum(gamma*result.red);
q->green = ClampToQuantum(gamma*result.green);
q->blue = ClampToQuantum(gamma*result.blue);
q->opacity = ClampToQuantum(result.opacity);
if (image->colorspace == CMYKColorspace)
q_indexes[x] = ClampToQuantum(gamma*result.index);
}
/* Count up changed pixels */
if ( ( p[r].red != q->red )
|| ( p[r].green != q->green )
|| ( p[r].blue != q->blue )
|| ( p[r].opacity != q->opacity )
|| ( image->colorspace == CMYKColorspace &&
p_indexes[r] != q_indexes[x] ) )
changed++; /* The pixel was changed in some way! */
p++;
q++;
} /* y */
if ( SyncCacheViewAuthenticPixels(q_view,exception) == MagickFalse)
status=MagickFalse;
if (image->progress_monitor != (MagickProgressMonitor) NULL)
{
MagickBooleanType
proceed;
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp critical (MagickCore_MorphologyImage)
#endif
proceed=SetImageProgress(image,MorphologyTag,progress++,image->rows);
if (proceed == MagickFalse)
status=MagickFalse;
}
} /* x */
result_image->type=image->type;
q_view=DestroyCacheView(q_view);
p_view=DestroyCacheView(p_view);
return(status ? (size_t) changed : 0);
}
/*
** Normal handling of horizontal or rectangular kernels (row by row)
*/
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp parallel for schedule(dynamic,4) shared(progress,status)
#endif
for (y=0; y < (ssize_t) image->rows; y++)
{
register const PixelPacket
*restrict p;
register const IndexPacket
*restrict p_indexes;
register PixelPacket
*restrict q;
register IndexPacket
*restrict q_indexes;
register ssize_t
x;
size_t
r;
if (status == MagickFalse)
continue;
p=GetCacheViewVirtualPixels(p_view, -offx, y-offy,
image->columns+kernel->width, kernel->height, exception);
q=GetCacheViewAuthenticPixels(q_view,0,y,result_image->columns,1,
exception);
if ((p == (const PixelPacket *) NULL) || (q == (PixelPacket *) NULL))
{
status=MagickFalse;
continue;
}
p_indexes=GetCacheViewVirtualIndexQueue(p_view);
q_indexes=GetCacheViewAuthenticIndexQueue(q_view);
r = (image->columns+kernel->width)*offy+offx; /* offset to origin in 'p' */
for (x=0; x < (ssize_t) image->columns; x++)
{
ssize_t
v;
register ssize_t
u;
register const double
*restrict k;
register const PixelPacket
*restrict k_pixels;
register const IndexPacket
*restrict k_indexes;
MagickPixelPacket
result,
min,
max;
/* Copy input image to the output image for unused channels
* This removes need for 'cloning' a new image every iteration
*/
*q = p[r];
if (image->colorspace == CMYKColorspace)
q_indexes[x] = p_indexes[r];
/* Defaults */
min.red =
min.green =
min.blue =
min.opacity =
min.index = (MagickRealType) QuantumRange;
max.red =
max.green =
max.blue =
max.opacity =
max.index = (MagickRealType) 0;
/* default result is the original pixel value */
result.red = (MagickRealType) p[r].red;
result.green = (MagickRealType) p[r].green;
result.blue = (MagickRealType) p[r].blue;
result.opacity = QuantumRange - (MagickRealType) p[r].opacity;
result.index = 0.0;
if ( image->colorspace == CMYKColorspace)
result.index = (MagickRealType) p_indexes[r];
switch (method) {
case ConvolveMorphology:
/* Set the bias of the weighted average output */
result.red =
result.green =
result.blue =
result.opacity =
result.index = bias;
break;
case DilateIntensityMorphology:
case ErodeIntensityMorphology:
/* use a boolean flag indicating when first match found */
result.red = 0.0; /* result is not used otherwise */
break;
default:
break;
}
switch ( method ) {
case ConvolveMorphology:
/* Weighted Average of pixels using reflected kernel
**
** NOTE for correct working of this operation for asymetrical
** kernels, the kernel needs to be applied in its reflected form.
** That is its values needs to be reversed.
**
** Correlation is actually the same as this but without reflecting
** the kernel, and thus 'lower-level' that Convolution. However
** as Convolution is the more common method used, and it does not
** really cost us much in terms of processing to use a reflected
** kernel, so it is Convolution that is implemented.
**
** Correlation will have its kernel reflected before calling
** this function to do a Convolve.
**
** For more details of Correlation vs Convolution see
** http://www.cs.umd.edu/~djacobs/CMSC426/Convolution.pdf
*/
k = &kernel->values[ kernel->width*kernel->height-1 ];
k_pixels = p;
k_indexes = p_indexes;
if ( ((channel & SyncChannels) == 0 ) ||
(image->matte == MagickFalse) )
{ /* No 'Sync' involved.
** Convolution is simple greyscale channel operation
*/
for (v=0; v < (ssize_t) kernel->height; v++) {
for (u=0; u < (ssize_t) kernel->width; u++, k--) {
if ( IsNan(*k) ) continue;
result.red += (*k)*k_pixels[u].red;
result.green += (*k)*k_pixels[u].green;
result.blue += (*k)*k_pixels[u].blue;
result.opacity += (*k)*k_pixels[u].opacity;
if ( image->colorspace == CMYKColorspace)
result.index += (*k)*k_indexes[u];
}
k_pixels += image->columns+kernel->width;
k_indexes += image->columns+kernel->width;
}
if ((channel & RedChannel) != 0)
q->red = ClampToQuantum(result.red);
if ((channel & GreenChannel) != 0)
q->green = ClampToQuantum(result.green);
if ((channel & BlueChannel) != 0)
q->blue = ClampToQuantum(result.blue);
if ((channel & OpacityChannel) != 0
&& image->matte == MagickTrue )
q->opacity = ClampToQuantum(result.opacity);
if ((channel & IndexChannel) != 0
&& image->colorspace == CMYKColorspace)
q_indexes[x] = ClampToQuantum(result.index);
}
else
{ /* Channel 'Sync' Flag, and Alpha Channel enabled.
** Weight the color channels with Alpha Channel so that
** transparent pixels are not part of the results.
*/
MagickRealType
alpha, /* alpha weighting of colors : kernel*alpha */
gamma; /* divisor, sum of color weighting values */
gamma=0.0;
for (v=0; v < (ssize_t) kernel->height; v++) {
for (u=0; u < (ssize_t) kernel->width; u++, k--) {
if ( IsNan(*k) ) continue;
alpha=(*k)*(QuantumScale*(QuantumRange-
k_pixels[u].opacity));
gamma += alpha;
result.red += alpha*k_pixels[u].red;
result.green += alpha*k_pixels[u].green;
result.blue += alpha*k_pixels[u].blue;
result.opacity += (*k)*k_pixels[u].opacity;
if ( image->colorspace == CMYKColorspace)
result.index += alpha*k_indexes[u];
}
k_pixels += image->columns+kernel->width;
k_indexes += image->columns+kernel->width;
}
/* Sync'ed channels, all channels are modified */
gamma=1.0/(fabs((double) gamma) <= MagickEpsilon ? 1.0 : gamma);
q->red = ClampToQuantum(gamma*result.red);
q->green = ClampToQuantum(gamma*result.green);
q->blue = ClampToQuantum(gamma*result.blue);
q->opacity = ClampToQuantum(result.opacity);
if (image->colorspace == CMYKColorspace)
q_indexes[x] = ClampToQuantum(gamma*result.index);
}
break;
case ErodeMorphology:
/* Minimum Value within kernel neighbourhood
**
** NOTE that the kernel is not reflected for this operation!
**
** NOTE: in normal Greyscale Morphology, the kernel value should
** be added to the real value, this is currently not done, due to
** the nature of the boolean kernels being used.
*/
k = kernel->values;
k_pixels = p;
k_indexes = p_indexes;
for (v=0; v < (ssize_t) kernel->height; v++) {
for (u=0; u < (ssize_t) kernel->width; u++, k++) {
if ( IsNan(*k) || (*k) < 0.5 ) continue;
Minimize(min.red, (double) k_pixels[u].red);
Minimize(min.green, (double) k_pixels[u].green);
Minimize(min.blue, (double) k_pixels[u].blue);
Minimize(min.opacity,
QuantumRange-(double) k_pixels[u].opacity);
if ( image->colorspace == CMYKColorspace)
Minimize(min.index, (double) k_indexes[u]);
}
k_pixels += image->columns+kernel->width;
k_indexes += image->columns+kernel->width;
}
break;
case DilateMorphology:
/* Maximum Value within kernel neighbourhood
**
** NOTE for correct working of this operation for asymetrical
** kernels, the kernel needs to be applied in its reflected form.
** That is its values needs to be reversed.
**
** NOTE: in normal Greyscale Morphology, the kernel value should
** be added to the real value, this is currently not done, due to
** the nature of the boolean kernels being used.
**
*/
k = &kernel->values[ kernel->width*kernel->height-1 ];
k_pixels = p;
k_indexes = p_indexes;
for (v=0; v < (ssize_t) kernel->height; v++) {
for (u=0; u < (ssize_t) kernel->width; u++, k--) {
if ( IsNan(*k) || (*k) < 0.5 ) continue;
Maximize(max.red, (double) k_pixels[u].red);
Maximize(max.green, (double) k_pixels[u].green);
Maximize(max.blue, (double) k_pixels[u].blue);
Maximize(max.opacity,
QuantumRange-(double) k_pixels[u].opacity);
if ( image->colorspace == CMYKColorspace)
Maximize(max.index, (double) k_indexes[u]);
}
k_pixels += image->columns+kernel->width;
k_indexes += image->columns+kernel->width;
}
break;
case HitAndMissMorphology:
case ThinningMorphology:
case ThickenMorphology:
/* Minimum of Foreground Pixel minus Maxumum of Background Pixels
**
** NOTE that the kernel is not reflected for this operation,
** and consists of both foreground and background pixel
** neighbourhoods, 0.0 for background, and 1.0 for foreground
** with either Nan or 0.5 values for don't care.
**
** Note that this will never produce a meaningless negative
** result. Such results can cause Thinning/Thicken to not work
** correctly when used against a greyscale image.
*/
k = kernel->values;
k_pixels = p;
k_indexes = p_indexes;
for (v=0; v < (ssize_t) kernel->height; v++) {
for (u=0; u < (ssize_t) kernel->width; u++, k++) {
if ( IsNan(*k) ) continue;
if ( (*k) > 0.7 )
{ /* minimim of foreground pixels */
Minimize(min.red, (double) k_pixels[u].red);
Minimize(min.green, (double) k_pixels[u].green);
Minimize(min.blue, (double) k_pixels[u].blue);
Minimize(min.opacity,
QuantumRange-(double) k_pixels[u].opacity);
if ( image->colorspace == CMYKColorspace)
Minimize(min.index, (double) k_indexes[u]);
}
else if ( (*k) < 0.3 )
{ /* maximum of background pixels */
Maximize(max.red, (double) k_pixels[u].red);
Maximize(max.green, (double) k_pixels[u].green);
Maximize(max.blue, (double) k_pixels[u].blue);
Maximize(max.opacity,
QuantumRange-(double) k_pixels[u].opacity);
if ( image->colorspace == CMYKColorspace)
Maximize(max.index, (double) k_indexes[u]);
}
}
k_pixels += image->columns+kernel->width;
k_indexes += image->columns+kernel->width;
}
/* Pattern Match if difference is positive */
min.red -= max.red; Maximize( min.red, 0.0 );
min.green -= max.green; Maximize( min.green, 0.0 );
min.blue -= max.blue; Maximize( min.blue, 0.0 );
min.opacity -= max.opacity; Maximize( min.opacity, 0.0 );
min.index -= max.index; Maximize( min.index, 0.0 );
break;
case ErodeIntensityMorphology:
/* Select Pixel with Minimum Intensity within kernel neighbourhood
**
** WARNING: the intensity test fails for CMYK and does not
** take into account the moderating effect of the alpha channel
** on the intensity.
**
** NOTE that the kernel is not reflected for this operation!
*/
k = kernel->values;
k_pixels = p;
k_indexes = p_indexes;
for (v=0; v < (ssize_t) kernel->height; v++) {
for (u=0; u < (ssize_t) kernel->width; u++, k++) {
if ( IsNan(*k) || (*k) < 0.5 ) continue;
if ( result.red == 0.0 ||
PixelIntensity(&(k_pixels[u])) < PixelIntensity(q) ) {
/* copy the whole pixel - no channel selection */
*q = k_pixels[u];
if ( result.red > 0.0 ) changed++;
result.red = 1.0;
}
}
k_pixels += image->columns+kernel->width;
k_indexes += image->columns+kernel->width;
}
break;
case DilateIntensityMorphology:
/* Select Pixel with Maximum Intensity within kernel neighbourhood
**
** WARNING: the intensity test fails for CMYK and does not
** take into account the moderating effect of the alpha channel
** on the intensity (yet).
**
** NOTE for correct working of this operation for asymetrical
** kernels, the kernel needs to be applied in its reflected form.
** That is its values needs to be reversed.
*/
k = &kernel->values[ kernel->width*kernel->height-1 ];
k_pixels = p;
k_indexes = p_indexes;
for (v=0; v < (ssize_t) kernel->height; v++) {
for (u=0; u < (ssize_t) kernel->width; u++, k--) {
if ( IsNan(*k) || (*k) < 0.5 ) continue; /* boolean kernel */
if ( result.red == 0.0 ||
PixelIntensity(&(k_pixels[u])) > PixelIntensity(q) ) {
/* copy the whole pixel - no channel selection */
*q = k_pixels[u];
if ( result.red > 0.0 ) changed++;
result.red = 1.0;
}
}
k_pixels += image->columns+kernel->width;
k_indexes += image->columns+kernel->width;
}
break;
case DistanceMorphology:
/* Add kernel Value and select the minimum value found.
** The result is a iterative distance from edge of image shape.
**
** All Distance Kernels are symetrical, but that may not always
** be the case. For example how about a distance from left edges?
** To work correctly with asymetrical kernels the reflected kernel
** needs to be applied.
**
** Actually this is really a GreyErode with a negative kernel!
**
*/
k = &kernel->values[ kernel->width*kernel->height-1 ];
k_pixels = p;
k_indexes = p_indexes;
for (v=0; v < (ssize_t) kernel->height; v++) {
for (u=0; u < (ssize_t) kernel->width; u++, k--) {
if ( IsNan(*k) ) continue;
Minimize(result.red, (*k)+k_pixels[u].red);
Minimize(result.green, (*k)+k_pixels[u].green);
Minimize(result.blue, (*k)+k_pixels[u].blue);
Minimize(result.opacity, (*k)+QuantumRange-k_pixels[u].opacity);
if ( image->colorspace == CMYKColorspace)
Minimize(result.index, (*k)+k_indexes[u]);
}
k_pixels += image->columns+kernel->width;
k_indexes += image->columns+kernel->width;
}
break;
case UndefinedMorphology:
default:
break; /* Do nothing */
}
/* Final mathematics of results (combine with original image?)
**
** NOTE: Difference Morphology operators Edge* and *Hat could also
** be done here but works better with iteration as a image difference
** in the controling function (below). Thicken and Thinning however
** should be done here so thay can be iterated correctly.
*/
switch ( method ) {
case HitAndMissMorphology:
case ErodeMorphology:
result = min; /* minimum of neighbourhood */
break;
case DilateMorphology:
result = max; /* maximum of neighbourhood */
break;
case ThinningMorphology:
/* subtract pattern match from original */
result.red -= min.red;
result.green -= min.green;
result.blue -= min.blue;
result.opacity -= min.opacity;
result.index -= min.index;
break;
case ThickenMorphology:
/* Add the pattern matchs to the original */
result.red += min.red;
result.green += min.green;
result.blue += min.blue;
result.opacity += min.opacity;
result.index += min.index;
break;
default:
/* result directly calculated or assigned */
break;
}
/* Assign the resulting pixel values - Clamping Result */
switch ( method ) {
case UndefinedMorphology:
case ConvolveMorphology:
case DilateIntensityMorphology:
case ErodeIntensityMorphology:
break; /* full pixel was directly assigned - not a channel method */
default:
if ((channel & RedChannel) != 0)
q->red = ClampToQuantum(result.red);
if ((channel & GreenChannel) != 0)
q->green = ClampToQuantum(result.green);
if ((channel & BlueChannel) != 0)
q->blue = ClampToQuantum(result.blue);
if ((channel & OpacityChannel) != 0
&& image->matte == MagickTrue )
q->opacity = ClampToQuantum(QuantumRange-result.opacity);
if ((channel & IndexChannel) != 0
&& image->colorspace == CMYKColorspace)
q_indexes[x] = ClampToQuantum(result.index);
break;
}
/* Count up changed pixels */
if ( ( p[r].red != q->red )
|| ( p[r].green != q->green )
|| ( p[r].blue != q->blue )
|| ( p[r].opacity != q->opacity )
|| ( image->colorspace == CMYKColorspace &&
p_indexes[r] != q_indexes[x] ) )
changed++; /* The pixel was changed in some way! */
p++;
q++;
} /* x */
if ( SyncCacheViewAuthenticPixels(q_view,exception) == MagickFalse)
status=MagickFalse;
if (image->progress_monitor != (MagickProgressMonitor) NULL)
{
MagickBooleanType
proceed;
#if defined(MAGICKCORE_OPENMP_SUPPORT)
#pragma omp critical (MagickCore_MorphologyImage)
#endif
proceed=SetImageProgress(image,MorphologyTag,progress++,image->rows);
if (proceed == MagickFalse)
status=MagickFalse;
}
} /* y */
result_image->type=image->type;
q_view=DestroyCacheView(q_view);
p_view=DestroyCacheView(p_view);
return(status ? (size_t) changed : 0);
}
MagickExport Image *MorphologyApply(const Image *image, const ChannelType
channel,const MorphologyMethod method, const ssize_t iterations,
const KernelInfo *kernel, const CompositeOperator compose,
const double bias, ExceptionInfo *exception)
{
Image
*curr_image, /* Image we are working with or iterating */
*work_image, /* secondary image for primative iteration */
*save_image, /* saved image - for 'edge' method only */
*rslt_image; /* resultant image - after multi-kernel handling */
KernelInfo
*reflected_kernel, /* A reflected copy of the kernel (if needed) */
*norm_kernel, /* the current normal un-reflected kernel */
*rflt_kernel, /* the current reflected kernel (if needed) */
*this_kernel; /* the kernel being applied */
MorphologyMethod
primative; /* the current morphology primative being applied */
CompositeOperator
rslt_compose; /* multi-kernel compose method for results to use */
MagickBooleanType
verbose; /* verbose output of results */
size_t
method_loop, /* Loop 1: number of compound method iterations */
method_limit, /* maximum number of compound method iterations */
kernel_number, /* Loop 2: the kernel number being applied */
stage_loop, /* Loop 3: primative loop for compound morphology */
stage_limit, /* how many primatives in this compound */
kernel_loop, /* Loop 4: iterate the kernel (basic morphology) */
kernel_limit, /* number of times to iterate kernel */
count, /* total count of primative steps applied */
changed, /* number pixels changed by last primative operation */
kernel_changed, /* total count of changed using iterated kernel */
method_changed; /* total count of changed over method iteration */
char
v_info[80];
assert(image != (Image *) NULL);
assert(image->signature == MagickSignature);
assert(kernel != (KernelInfo *) NULL);
assert(kernel->signature == MagickSignature);
assert(exception != (ExceptionInfo *) NULL);
assert(exception->signature == MagickSignature);
count = 0; /* number of low-level morphology primatives performed */
if ( iterations == 0 )
return((Image *)NULL); /* null operation - nothing to do! */
kernel_limit = (size_t) iterations;
if ( iterations < 0 ) /* negative interations = infinite (well alomst) */
kernel_limit = image->columns > image->rows ? image->columns : image->rows;
verbose = ( GetImageArtifact(image,"verbose") != (const char *) NULL ) ?
MagickTrue : MagickFalse;
/* initialise for cleanup */
curr_image = (Image *) image;
work_image = save_image = rslt_image = (Image *) NULL;
reflected_kernel = (KernelInfo *) NULL;
/* Initialize specific methods
* + which loop should use the given iteratations
* + how many primatives make up the compound morphology
* + multi-kernel compose method to use (by default)
*/
method_limit = 1; /* just do method once, unless otherwise set */
stage_limit = 1; /* assume method is not a compount */
rslt_compose = compose; /* and we are composing multi-kernels as given */
switch( method ) {
case SmoothMorphology: /* 4 primative compound morphology */
stage_limit = 4;
break;
case OpenMorphology: /* 2 primative compound morphology */
case OpenIntensityMorphology:
case TopHatMorphology:
case CloseMorphology:
case CloseIntensityMorphology:
case BottomHatMorphology:
case EdgeMorphology:
stage_limit = 2;
break;
case HitAndMissMorphology:
rslt_compose = LightenCompositeOp; /* Union of multi-kernel results */
/* FALL THUR */
case ThinningMorphology:
case ThickenMorphology:
method_limit = kernel_limit; /* iterate the whole method */
kernel_limit = 1; /* do not do kernel iteration */
break;
default:
break;
}
/* Handle user (caller) specified multi-kernel composition method */
if ( compose != UndefinedCompositeOp )
rslt_compose = compose; /* override default composition for method */
if ( rslt_compose == UndefinedCompositeOp )
rslt_compose = NoCompositeOp; /* still not defined! Then re-iterate */
/* Some methods require a reflected kernel to use with primatives.
* Create the reflected kernel for those methods. */
switch ( method ) {
case CorrelateMorphology:
case CloseMorphology:
case CloseIntensityMorphology:
case BottomHatMorphology:
case SmoothMorphology:
reflected_kernel = CloneKernelInfo(kernel);
if (reflected_kernel == (KernelInfo *) NULL)
goto error_cleanup;
RotateKernelInfo(reflected_kernel,180);
break;
default:
break;
}
/* Loop 1: iterate the compound method */
method_loop = 0;
method_changed = 1;
while ( method_loop < method_limit && method_changed > 0 ) {
method_loop++;
method_changed = 0;
/* Loop 2: iterate over each kernel in a multi-kernel list */
norm_kernel = (KernelInfo *) kernel;
this_kernel = (KernelInfo *) kernel;
rflt_kernel = reflected_kernel;
kernel_number = 0;
while ( norm_kernel != NULL ) {
/* Loop 3: Compound Morphology Staging - Select Primative to apply */
stage_loop = 0; /* the compound morphology stage number */
while ( stage_loop < stage_limit ) {
stage_loop++; /* The stage of the compound morphology */
/* Select primative morphology for this stage of compound method */
this_kernel = norm_kernel; /* default use unreflected kernel */
primative = method; /* Assume method is a primative */
switch( method ) {
case ErodeMorphology: /* just erode */
case EdgeInMorphology: /* erode and image difference */
primative = ErodeMorphology;
break;
case DilateMorphology: /* just dilate */
case EdgeOutMorphology: /* dilate and image difference */
primative = DilateMorphology;
break;
case OpenMorphology: /* erode then dialate */
case TopHatMorphology: /* open and image difference */
primative = ErodeMorphology;
if ( stage_loop == 2 )
primative = DilateMorphology;
break;
case OpenIntensityMorphology:
primative = ErodeIntensityMorphology;
if ( stage_loop == 2 )
primative = DilateIntensityMorphology;
break;
case CloseMorphology: /* dilate, then erode */
case BottomHatMorphology: /* close and image difference */
this_kernel = rflt_kernel; /* use the reflected kernel */
primative = DilateMorphology;
if ( stage_loop == 2 )
primative = ErodeMorphology;
break;
case CloseIntensityMorphology:
this_kernel = rflt_kernel; /* use the reflected kernel */
primative = DilateIntensityMorphology;
if ( stage_loop == 2 )
primative = ErodeIntensityMorphology;
break;
case SmoothMorphology: /* open, close */
switch ( stage_loop ) {
case 1: /* start an open method, which starts with Erode */
primative = ErodeMorphology;
break;
case 2: /* now Dilate the Erode */
primative = DilateMorphology;
break;
case 3: /* Reflect kernel a close */
this_kernel = rflt_kernel; /* use the reflected kernel */
primative = DilateMorphology;
break;
case 4: /* Finish the Close */
this_kernel = rflt_kernel; /* use the reflected kernel */
primative = ErodeMorphology;
break;
}
break;
case EdgeMorphology: /* dilate and erode difference */
primative = DilateMorphology;
if ( stage_loop == 2 ) {
save_image = curr_image; /* save the image difference */
curr_image = (Image *) image;
primative = ErodeMorphology;
}
break;
case CorrelateMorphology:
/* A Correlation is a Convolution with a reflected kernel.
** However a Convolution is a weighted sum using a reflected
** kernel. It may seem stange to convert a Correlation into a
** Convolution as the Correlation is the simplier method, but
** Convolution is much more commonly used, and it makes sense to
** implement it directly so as to avoid the need to duplicate the
** kernel when it is not required (which is typically the
** default).
*/
this_kernel = rflt_kernel; /* use the reflected kernel */
primative = ConvolveMorphology;
break;
default:
break;
}
assert( this_kernel != (KernelInfo *) NULL );
/* Extra information for debugging compound operations */
if ( verbose == MagickTrue ) {
if ( stage_limit > 1 )
(void) FormatMagickString(v_info,MaxTextExtent,"%s:%.20g.%.20g -> ",
MagickOptionToMnemonic(MagickMorphologyOptions,method),(double)
method_loop,(double) stage_loop);
else if ( primative != method )
(void) FormatMagickString(v_info, MaxTextExtent, "%s:%.20g -> ",
MagickOptionToMnemonic(MagickMorphologyOptions, method),(double)
method_loop);
else
v_info[0] = '\0';
}
/* Loop 4: Iterate the kernel with primative */
kernel_loop = 0;
kernel_changed = 0;
changed = 1;
while ( kernel_loop < kernel_limit && changed > 0 ) {
kernel_loop++; /* the iteration of this kernel */
/* Create a destination image, if not yet defined */
if ( work_image == (Image *) NULL )
{
work_image=CloneImage(image,0,0,MagickTrue,exception);
if (work_image == (Image *) NULL)
goto error_cleanup;
if (SetImageStorageClass(work_image,DirectClass) == MagickFalse)
{
InheritException(exception,&work_image->exception);
goto error_cleanup;
}
}
/* APPLY THE MORPHOLOGICAL PRIMITIVE (curr -> work) */
count++;
changed = MorphologyPrimitive(curr_image, work_image, primative,
channel, this_kernel, bias, exception);
kernel_changed += changed;
method_changed += changed;
if ( verbose == MagickTrue ) {
if ( kernel_loop > 1 )
fprintf(stderr, "\n"); /* add end-of-line from previous */
(void) fprintf(stderr, "%s%s%s:%.20g.%.20g #%.20g => Changed %.20g",
v_info,MagickOptionToMnemonic(MagickMorphologyOptions,
primative),(this_kernel == rflt_kernel ) ? "*" : "",
(double) (method_loop+kernel_loop-1),(double) kernel_number,
(double) count,(double) changed);
}
/* prepare next loop */
{ Image *tmp = work_image; /* swap images for iteration */
work_image = curr_image;
curr_image = tmp;
}
if ( work_image == image )
work_image = (Image *) NULL; /* replace input 'image' */
} /* End Loop 4: Iterate the kernel with primative */
if ( verbose == MagickTrue && kernel_changed != changed )
fprintf(stderr, " Total %.20g",(double) kernel_changed);
if ( verbose == MagickTrue && stage_loop < stage_limit )
fprintf(stderr, "\n"); /* add end-of-line before looping */
#if 0
fprintf(stderr, "--E-- image=0x%lx\n", (unsigned long)image);
fprintf(stderr, " curr =0x%lx\n", (unsigned long)curr_image);
fprintf(stderr, " work =0x%lx\n", (unsigned long)work_image);
fprintf(stderr, " save =0x%lx\n", (unsigned long)save_image);
fprintf(stderr, " union=0x%lx\n", (unsigned long)rslt_image);
#endif
} /* End Loop 3: Primative (staging) Loop for Coumpound Methods */
/* Final Post-processing for some Compound Methods
**
** The removal of any 'Sync' channel flag in the Image Compositon
** below ensures the methematical compose method is applied in a
** purely mathematical way, and only to the selected channels.
** Turn off SVG composition 'alpha blending'.
*/
switch( method ) {
case EdgeOutMorphology:
case EdgeInMorphology:
case TopHatMorphology:
case BottomHatMorphology:
if ( verbose == MagickTrue )
fprintf(stderr, "\n%s: Difference with original image",
MagickOptionToMnemonic(MagickMorphologyOptions, method) );
(void) CompositeImageChannel(curr_image,
(ChannelType) (channel & ~SyncChannels),
DifferenceCompositeOp, image, 0, 0);
break;
case EdgeMorphology:
if ( verbose == MagickTrue )
fprintf(stderr, "\n%s: Difference of Dilate and Erode",
MagickOptionToMnemonic(MagickMorphologyOptions, method) );
(void) CompositeImageChannel(curr_image,
(ChannelType) (channel & ~SyncChannels),
DifferenceCompositeOp, save_image, 0, 0);
save_image = DestroyImage(save_image); /* finished with save image */
break;
default:
break;
}
/* multi-kernel handling: re-iterate, or compose results */
if ( kernel->next == (KernelInfo *) NULL )
rslt_image = curr_image; /* just return the resulting image */
else if ( rslt_compose == NoCompositeOp )
{ if ( verbose == MagickTrue ) {
if ( this_kernel->next != (KernelInfo *) NULL )
fprintf(stderr, " (re-iterate)");
else
fprintf(stderr, " (done)");
}
rslt_image = curr_image; /* return result, and re-iterate */
}
else if ( rslt_image == (Image *) NULL)
{ if ( verbose == MagickTrue )
fprintf(stderr, " (save for compose)");
rslt_image = curr_image;
curr_image = (Image *) image; /* continue with original image */
}
else
{ /* add the new 'current' result to the composition
**
** The removal of any 'Sync' channel flag in the Image Compositon
** below ensures the methematical compose method is applied in a
** purely mathematical way, and only to the selected channels.
** Turn off SVG composition 'alpha blending'.
**
** The compose image order is specifically so that the new image can
** be subtarcted 'Minus' from the collected result, to allow you to
** convert a HitAndMiss methd into a Thinning method.
*/
if ( verbose == MagickTrue )
fprintf(stderr, " (compose \"%s\")",
MagickOptionToMnemonic(MagickComposeOptions, rslt_compose) );
(void) CompositeImageChannel(curr_image,
(ChannelType) (channel & ~SyncChannels), rslt_compose,
rslt_image, 0, 0);
rslt_image = DestroyImage(rslt_image);
rslt_image = curr_image;
curr_image = (Image *) image; /* continue with original image */
}
if ( verbose == MagickTrue )
fprintf(stderr, "\n");
/* loop to the next kernel in a multi-kernel list */
norm_kernel = norm_kernel->next;
if ( rflt_kernel != (KernelInfo *) NULL )
rflt_kernel = rflt_kernel->next;
kernel_number++;
} /* End Loop 2: Loop over each kernel */
} /* End Loop 1: compound method interation */
goto exit_cleanup;
/* Yes goto's are bad, but it makes cleanup lot more efficient */
error_cleanup:
if ( curr_image != (Image *) NULL &&
curr_image != rslt_image &&
curr_image != image )
curr_image = DestroyImage(curr_image);
if ( rslt_image != (Image *) NULL )
rslt_image = DestroyImage(rslt_image);
exit_cleanup:
if ( curr_image != (Image *) NULL &&
curr_image != rslt_image &&
curr_image != image )
curr_image = DestroyImage(curr_image);
if ( work_image != (Image *) NULL )
work_image = DestroyImage(work_image);
if ( save_image != (Image *) NULL )
save_image = DestroyImage(save_image);
if ( reflected_kernel != (KernelInfo *) NULL )
reflected_kernel = DestroyKernelInfo(reflected_kernel);
return(rslt_image);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% M o r p h o l o g y I m a g e C h a n n e l %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% MorphologyImageChannel() applies a user supplied kernel to the image
% according to the given mophology method.
%
% This function applies any and all user defined settings before calling
% the above internal function MorphologyApply().
%
% User defined settings include...
% * Output Bias for Convolution and correlation ("-bias")
% * Kernel Scale/normalize settings ("-set 'option:convolve:scale'")
% This can also includes the addition of a scaled unity kernel.
% * Show Kernel being applied ("-set option:showkernel 1")
%
% The format of the MorphologyImage method is:
%
% Image *MorphologyImage(const Image *image,MorphologyMethod method,
% const ssize_t iterations,KernelInfo *kernel,ExceptionInfo *exception)
%
% Image *MorphologyImageChannel(const Image *image, const ChannelType
% channel,MorphologyMethod method,const ssize_t iterations,
% KernelInfo *kernel,ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image: the image.
%
% o method: the morphology method to be applied.
%
% o iterations: apply the operation this many times (or no change).
% A value of -1 means loop until no change found.
% How this is applied may depend on the morphology method.
% Typically this is a value of 1.
%
% o channel: the channel type.
%
% o kernel: An array of double representing the morphology kernel.
% Warning: kernel may be normalized for the Convolve method.
%
% o exception: return any errors or warnings in this structure.
%
*/
MagickExport Image *MorphologyImageChannel(const Image *image,
const ChannelType channel,const MorphologyMethod method,
const ssize_t iterations,const KernelInfo *kernel,ExceptionInfo *exception)
{
const char
*artifact;
KernelInfo
*curr_kernel;
CompositeOperator
compose;
Image
*morphology_image;
/* Apply Convolve/Correlate Normalization and Scaling Factors.
* This is done BEFORE the ShowKernelInfo() function is called so that
* users can see the results of the 'option:convolve:scale' option.
*/
curr_kernel = (KernelInfo *) kernel;
if ( method == ConvolveMorphology || method == CorrelateMorphology )
{
artifact = GetImageArtifact(image,"convolve:scale");
if ( artifact != (const char *)NULL ) {
if ( curr_kernel == kernel )
curr_kernel = CloneKernelInfo(kernel);
if (curr_kernel == (KernelInfo *) NULL) {
curr_kernel=DestroyKernelInfo(curr_kernel);
return((Image *) NULL);
}
ScaleGeometryKernelInfo(curr_kernel, artifact);
}
}
/* display the (normalized) kernel via stderr */
artifact = GetImageArtifact(image,"showkernel");
if ( artifact == (const char *) NULL)
artifact = GetImageArtifact(image,"convolve:showkernel");
if ( artifact == (const char *) NULL)
artifact = GetImageArtifact(image,"morphology:showkernel");
if ( artifact != (const char *) NULL)
ShowKernelInfo(curr_kernel);
/* Override the default handling of multi-kernel morphology results
* If 'Undefined' use the default method
* If 'None' (default for 'Convolve') re-iterate previous result
* Otherwise merge resulting images using compose method given.
* Default for 'HitAndMiss' is 'Lighten'.
*/
compose = UndefinedCompositeOp; /* use default for method */
artifact = GetImageArtifact(image,"morphology:compose");
if ( artifact != (const char *) NULL)
compose = (CompositeOperator) ParseMagickOption(
MagickComposeOptions,MagickFalse,artifact);
/* Apply the Morphology */
morphology_image = MorphologyApply(image, channel, method, iterations,
curr_kernel, compose, image->bias, exception);
/* Cleanup and Exit */
if ( curr_kernel != kernel )
curr_kernel=DestroyKernelInfo(curr_kernel);
return(morphology_image);
}
MagickExport Image *MorphologyImage(const Image *image, const MorphologyMethod
method, const ssize_t iterations,const KernelInfo *kernel, ExceptionInfo
*exception)
{
Image
*morphology_image;
morphology_image=MorphologyImageChannel(image,DefaultChannels,method,
iterations,kernel,exception);
return(morphology_image);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
+ R o t a t e K e r n e l I n f o %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% RotateKernelInfo() rotates the kernel by the angle given.
%
% Currently it is restricted to 90 degree angles, of either 1D kernels
% or square kernels. And 'circular' rotations of 45 degrees for 3x3 kernels.
% It will ignore usless rotations for specific 'named' built-in kernels.
%
% The format of the RotateKernelInfo method is:
%
% void RotateKernelInfo(KernelInfo *kernel, double angle)
%
% A description of each parameter follows:
%
% o kernel: the Morphology/Convolution kernel
%
% o angle: angle to rotate in degrees
%
% This function is currently internal to this module only, but can be exported
% to other modules if needed.
*/
static void RotateKernelInfo(KernelInfo *kernel, double angle)
{
/* angle the lower kernels first */
if ( kernel->next != (KernelInfo *) NULL)
RotateKernelInfo(kernel->next, angle);
/* WARNING: Currently assumes the kernel (rightly) is horizontally symetrical
**
** TODO: expand beyond simple 90 degree rotates, flips and flops
*/
/* Modulus the angle */
angle = fmod(angle, 360.0);
if ( angle < 0 )
angle += 360.0;
if ( 337.5 < angle || angle <= 22.5 )
return; /* Near zero angle - no change! - At least not at this time */
/* Handle special cases */
switch (kernel->type) {
/* These built-in kernels are cylindrical kernels, rotating is useless */
case GaussianKernel:
case DoGKernel:
case LoGKernel:
case DiskKernel:
case PeaksKernel:
case LaplacianKernel:
case ChebyshevKernel:
case ManhattanKernel:
case EuclideanKernel:
return;
/* These may be rotatable at non-90 angles in the future */
/* but simply rotating them in multiples of 90 degrees is useless */
case SquareKernel:
case DiamondKernel:
case PlusKernel:
case CrossKernel:
return;
/* These only allows a +/-90 degree rotation (by transpose) */
/* A 180 degree rotation is useless */
case BlurKernel:
case RectangleKernel:
if ( 135.0 < angle && angle <= 225.0 )
return;
if ( 225.0 < angle && angle <= 315.0 )
angle -= 180;
break;
default:
break;
}
/* Attempt rotations by 45 degrees */
if ( 22.5 < fmod(angle,90.0) && fmod(angle,90.0) <= 67.5 )
{
if ( kernel->width == 3 && kernel->height == 3 )
{ /* Rotate a 3x3 square by 45 degree angle */
MagickRealType t = kernel->values[0];
kernel->values[0] = kernel->values[3];
kernel->values[3] = kernel->values[6];
kernel->values[6] = kernel->values[7];
kernel->values[7] = kernel->values[8];
kernel->values[8] = kernel->values[5];
kernel->values[5] = kernel->values[2];
kernel->values[2] = kernel->values[1];
kernel->values[1] = t;
/* rotate non-centered origin */
if ( kernel->x != 1 || kernel->y != 1 ) {
ssize_t x,y;
x = (ssize_t) kernel->x-1;
y = (ssize_t) kernel->y-1;
if ( x == y ) x = 0;
else if ( x == 0 ) x = -y;
else if ( x == -y ) y = 0;
else if ( y == 0 ) y = x;
kernel->x = (ssize_t) x+1;
kernel->y = (ssize_t) y+1;
}
angle = fmod(angle+315.0, 360.0); /* angle reduced 45 degrees */
kernel->angle = fmod(kernel->angle+45.0, 360.0);
}
else
perror("Unable to rotate non-3x3 kernel by 45 degrees");
}
if ( 45.0 < fmod(angle, 180.0) && fmod(angle,180.0) <= 135.0 )
{
if ( kernel->width == 1 || kernel->height == 1 )
{ /* Do a transpose of a 1 dimentional kernel,
** which results in a fast 90 degree rotation of some type.
*/
ssize_t
t;
t = (ssize_t) kernel->width;
kernel->width = kernel->height;
kernel->height = (size_t) t;
t = kernel->x;
kernel->x = kernel->y;
kernel->y = t;
if ( kernel->width == 1 ) {
angle = fmod(angle+270.0, 360.0); /* angle reduced 90 degrees */
kernel->angle = fmod(kernel->angle+90.0, 360.0);
} else {
angle = fmod(angle+90.0, 360.0); /* angle increased 90 degrees */
kernel->angle = fmod(kernel->angle+270.0, 360.0);
}
}
else if ( kernel->width == kernel->height )
{ /* Rotate a square array of values by 90 degrees */
{ register size_t
i,j,x,y;
register MagickRealType
*k,t;
k=kernel->values;
for( i=0, x=kernel->width-1; i<=x; i++, x--)
for( j=0, y=kernel->height-1; j<y; j++, y--)
{ t = k[i+j*kernel->width];
k[i+j*kernel->width] = k[j+x*kernel->width];
k[j+x*kernel->width] = k[x+y*kernel->width];
k[x+y*kernel->width] = k[y+i*kernel->width];
k[y+i*kernel->width] = t;
}
}
/* rotate the origin - relative to center of array */
{ register ssize_t x,y;
x = (ssize_t) (kernel->x*2-kernel->width+1);
y = (ssize_t) (kernel->y*2-kernel->height+1);
kernel->x = (ssize_t) ( -y +(ssize_t) kernel->width-1)/2;
kernel->y = (ssize_t) ( +x +(ssize_t) kernel->height-1)/2;
}
angle = fmod(angle+270.0, 360.0); /* angle reduced 90 degrees */
kernel->angle = fmod(kernel->angle+90.0, 360.0);
}
else
perror("Unable to rotate a non-square, non-linear kernel 90 degrees");
}
if ( 135.0 < angle && angle <= 225.0 )
{
/* For a 180 degree rotation - also know as a reflection
* This is actually a very very common operation!
* Basically all that is needed is a reversal of the kernel data!
* And a reflection of the origon
*/
size_t
i,j;
register double
*k,t;
k=kernel->values;
for ( i=0, j=kernel->width*kernel->height-1; i<j; i++, j--)
t=k[i], k[i]=k[j], k[j]=t;
kernel->x = (ssize_t) kernel->width - kernel->x - 1;
kernel->y = (ssize_t) kernel->height - kernel->y - 1;
angle = fmod(angle-180.0, 360.0); /* angle+180 degrees */
kernel->angle = fmod(kernel->angle+180.0, 360.0);
}
/* At this point angle should at least between -45 (315) and +45 degrees
* In the future some form of non-orthogonal angled rotates could be
* performed here, posibily with a linear kernel restriction.
*/
return;
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% S c a l e G e o m e t r y K e r n e l I n f o %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ScaleGeometryKernelInfo() takes a geometry argument string, typically
% provided as a "-set option:convolve:scale {geometry}" user setting,
% and modifies the kernel according to the parsed arguments of that setting.
%
% The first argument (and any normalization flags) are passed to
% ScaleKernelInfo() to scale/normalize the kernel. The second argument
% is then passed to UnityAddKernelInfo() to add a scled unity kernel
% into the scaled/normalized kernel.
%
% The format of the ScaleKernelInfo method is:
%
% void ScaleKernelInfo(KernelInfo *kernel, const double scaling_factor,
% const MagickStatusType normalize_flags )
%
% A description of each parameter follows:
%
% o kernel: the Morphology/Convolution kernel to modify
%
% o geometry:
% The geometry string to parse, typically from the user provided
% "-set option:convolve:scale {geometry}" setting.
%
*/
MagickExport void ScaleGeometryKernelInfo (KernelInfo *kernel,
const char *geometry)
{
GeometryFlags
flags;
GeometryInfo
args;
SetGeometryInfo(&args);
flags = (GeometryFlags) ParseGeometry(geometry, &args);
#if 0
/* For Debugging Geometry Input */
fprintf(stderr, "Geometry = 0x%04X : %lg x %lg %+lg %+lg\n",
flags, args.rho, args.sigma, args.xi, args.psi );
#endif
if ( (flags & PercentValue) != 0 ) /* Handle Percentage flag*/
args.rho *= 0.01, args.sigma *= 0.01;
if ( (flags & RhoValue) == 0 ) /* Set Defaults for missing args */
args.rho = 1.0;
if ( (flags & SigmaValue) == 0 )
args.sigma = 0.0;
/* Scale/Normalize the input kernel */
ScaleKernelInfo(kernel, args.rho, flags);
/* Add Unity Kernel, for blending with original */
if ( (flags & SigmaValue) != 0 )
UnityAddKernelInfo(kernel, args.sigma);
return;
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% S c a l e K e r n e l I n f o %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ScaleKernelInfo() scales the given kernel list by the given amount, with or
% without normalization of the sum of the kernel values (as per given flags).
%
% By default (no flags given) the values within the kernel is scaled
% directly using given scaling factor without change.
%
% If either of the two 'normalize_flags' are given the kernel will first be
% normalized and then further scaled by the scaling factor value given.
%
% Kernel normalization ('normalize_flags' given) is designed to ensure that
% any use of the kernel scaling factor with 'Convolve' or 'Correlate'
% morphology methods will fall into -1.0 to +1.0 range. Note that for
% non-HDRI versions of IM this may cause images to have any negative results
% clipped, unless some 'bias' is used.
%
% More specifically. Kernels which only contain positive values (such as a
% 'Gaussian' kernel) will be scaled so that those values sum to +1.0,
% ensuring a 0.0 to +1.0 output range for non-HDRI images.
%
% For Kernels that contain some negative values, (such as 'Sharpen' kernels)
% the kernel will be scaled by the absolute of the sum of kernel values, so
% that it will generally fall within the +/- 1.0 range.
%
% For kernels whose values sum to zero, (such as 'Laplician' kernels) kernel
% will be scaled by just the sum of the postive values, so that its output
% range will again fall into the +/- 1.0 range.
%
% For special kernels designed for locating shapes using 'Correlate', (often
% only containing +1 and -1 values, representing foreground/brackground
% matching) a special normalization method is provided to scale the positive
% values seperatally to those of the negative values, so the kernel will be
% forced to become a zero-sum kernel better suited to such searches.
%
% WARNING: Correct normalization of the kernel assumes that the '*_range'
% attributes within the kernel structure have been correctly set during the
% kernels creation.
%
% NOTE: The values used for 'normalize_flags' have been selected specifically
% to match the use of geometry options, so that '!' means NormalizeValue, '^'
% means CorrelateNormalizeValue. All other GeometryFlags values are ignored.
%
% The format of the ScaleKernelInfo method is:
%
% void ScaleKernelInfo(KernelInfo *kernel, const double scaling_factor,
% const MagickStatusType normalize_flags )
%
% A description of each parameter follows:
%
% o kernel: the Morphology/Convolution kernel
%
% o scaling_factor:
% multiply all values (after normalization) by this factor if not
% zero. If the kernel is normalized regardless of any flags.
%
% o normalize_flags:
% GeometryFlags defining normalization method to use.
% specifically: NormalizeValue, CorrelateNormalizeValue,
% and/or PercentValue
%
*/
MagickExport void ScaleKernelInfo(KernelInfo *kernel,
const double scaling_factor,const GeometryFlags normalize_flags)
{
register ssize_t
i;
register double
pos_scale,
neg_scale;
/* do the other kernels in a multi-kernel list first */
if ( kernel->next != (KernelInfo *) NULL)
ScaleKernelInfo(kernel->next, scaling_factor, normalize_flags);
/* Normalization of Kernel */
pos_scale = 1.0;
if ( (normalize_flags&NormalizeValue) != 0 ) {
if ( fabs(kernel->positive_range + kernel->negative_range) > MagickEpsilon )
/* non-zero-summing kernel (generally positive) */
pos_scale = fabs(kernel->positive_range + kernel->negative_range);
else
/* zero-summing kernel */
pos_scale = kernel->positive_range;
}
/* Force kernel into a normalized zero-summing kernel */
if ( (normalize_flags&CorrelateNormalizeValue) != 0 ) {
pos_scale = ( fabs(kernel->positive_range) > MagickEpsilon )
? kernel->positive_range : 1.0;
neg_scale = ( fabs(kernel->negative_range) > MagickEpsilon )
? -kernel->negative_range : 1.0;
}
else
neg_scale = pos_scale;
/* finialize scaling_factor for positive and negative components */
pos_scale = scaling_factor/pos_scale;
neg_scale = scaling_factor/neg_scale;
for (i=0; i < (ssize_t) (kernel->width*kernel->height); i++)
if ( ! IsNan(kernel->values[i]) )
kernel->values[i] *= (kernel->values[i] >= 0) ? pos_scale : neg_scale;
/* convolution output range */
kernel->positive_range *= pos_scale;
kernel->negative_range *= neg_scale;
/* maximum and minimum values in kernel */
kernel->maximum *= (kernel->maximum >= 0.0) ? pos_scale : neg_scale;
kernel->minimum *= (kernel->minimum >= 0.0) ? pos_scale : neg_scale;
/* swap kernel settings if user's scaling factor is negative */
if ( scaling_factor < MagickEpsilon ) {
double t;
t = kernel->positive_range;
kernel->positive_range = kernel->negative_range;
kernel->negative_range = t;
t = kernel->maximum;
kernel->maximum = kernel->minimum;
kernel->minimum = 1;
}
return;
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% S h o w K e r n e l I n f o %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ShowKernelInfo() outputs the details of the given kernel defination to
% standard error, generally due to a users 'showkernel' option request.
%
% The format of the ShowKernel method is:
%
% void ShowKernelInfo(KernelInfo *kernel)
%
% A description of each parameter follows:
%
% o kernel: the Morphology/Convolution kernel
%
*/
MagickExport void ShowKernelInfo(KernelInfo *kernel)
{
KernelInfo
*k;
size_t
c, i, u, v;
for (c=0, k=kernel; k != (KernelInfo *) NULL; c++, k=k->next ) {
fprintf(stderr, "Kernel");
if ( kernel->next != (KernelInfo *) NULL )
fprintf(stderr, " #%lu", (unsigned long) c );
fprintf(stderr, " \"%s",
MagickOptionToMnemonic(MagickKernelOptions, k->type) );
if ( fabs(k->angle) > MagickEpsilon )
fprintf(stderr, "@%lg", k->angle);
fprintf(stderr, "\" of size %lux%lu%+ld%+ld",(unsigned long) k->width,
(unsigned long) k->height,(long) k->x,(long) k->y);
fprintf(stderr,
" with values from %.*lg to %.*lg\n",
GetMagickPrecision(), k->minimum,
GetMagickPrecision(), k->maximum);
fprintf(stderr, "Forming a output range from %.*lg to %.*lg",
GetMagickPrecision(), k->negative_range,
GetMagickPrecision(), k->positive_range);
if ( fabs(k->positive_range+k->negative_range) < MagickEpsilon )
fprintf(stderr, " (Zero-Summing)\n");
else if ( fabs(k->positive_range+k->negative_range-1.0) < MagickEpsilon )
fprintf(stderr, " (Normalized)\n");
else
fprintf(stderr, " (Sum %.*lg)\n",
GetMagickPrecision(), k->positive_range+k->negative_range);
for (i=v=0; v < k->height; v++) {
fprintf(stderr, "%2lu:", (unsigned long) v );
for (u=0; u < k->width; u++, i++)
if ( IsNan(k->values[i]) )
fprintf(stderr," %*s", GetMagickPrecision()+3, "nan");
else
fprintf(stderr," %*.*lg", GetMagickPrecision()+3,
GetMagickPrecision(), k->values[i]);
fprintf(stderr,"\n");
}
}
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% U n i t y A d d K e r n a l I n f o %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% UnityAddKernelInfo() Adds a given amount of the 'Unity' Convolution Kernel
% to the given pre-scaled and normalized Kernel. This in effect adds that
% amount of the original image into the resulting convolution kernel. This
% value is usually provided by the user as a percentage value in the
% 'convolve:scale' setting.
%
% The resulting effect is to convert the defined kernels into blended
% soft-blurs, unsharp kernels or into sharpening kernels.
%
% The format of the UnityAdditionKernelInfo method is:
%
% void UnityAdditionKernelInfo(KernelInfo *kernel, const double scale )
%
% A description of each parameter follows:
%
% o kernel: the Morphology/Convolution kernel
%
% o scale:
% scaling factor for the unity kernel to be added to
% the given kernel.
%
*/
MagickExport void UnityAddKernelInfo(KernelInfo *kernel,
const double scale)
{
/* do the other kernels in a multi-kernel list first */
if ( kernel->next != (KernelInfo *) NULL)
UnityAddKernelInfo(kernel->next, scale);
/* Add the scaled unity kernel to the existing kernel */
kernel->values[kernel->x+kernel->y*kernel->width] += scale;
CalcKernelMetaData(kernel); /* recalculate the meta-data */
return;
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% Z e r o K e r n e l N a n s %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ZeroKernelNans() replaces any special 'nan' value that may be present in
% the kernel with a zero value. This is typically done when the kernel will
% be used in special hardware (GPU) convolution processors, to simply
% matters.
%
% The format of the ZeroKernelNans method is:
%
% void ZeroKernelNans (KernelInfo *kernel)
%
% A description of each parameter follows:
%
% o kernel: the Morphology/Convolution kernel
%
*/
MagickExport void ZeroKernelNans(KernelInfo *kernel)
{
register size_t
i;
/* do the other kernels in a multi-kernel list first */
if ( kernel->next != (KernelInfo *) NULL)
ZeroKernelNans(kernel->next);
for (i=0; i < (kernel->width*kernel->height); i++)
if ( IsNan(kernel->values[i]) )
kernel->values[i] = 0.0;
return;
}