image=AllocateImage(image_info);
if (SetImageExtent(image,640,480) == MagickFalse)
  { /* an exception was thrown */ }
(void) QueryMagickColor("red",&image->background_color,&image->exception);
SetImageBackgroundColor(image);

(void) strcpy(image_info->filename,"image.jpg"):
image=ReadImage(image_info,exception);
if (image == (Image *) NULL)
  { /* an exception was thrown */ }

image=BlobToImage(blob_info,blob,extent,exception);
if (image == (Image *) NULL)
  { /* an exception was thrown */ }

$ identify -version
Version: ImageMagick 7.1.2-25 2026-06-04 Q16-HDRI https://imagemagick.org

const Quantum
  *p;

Quantum
  *q;

ssize_t
  x,
  y;

destination=CloneImage(source,source->columns,source->rows,MagickTrue,exception);
if (destination == (Image *) NULL)
  { /* an exception was thrown */ }
for (y=0; y < (ssize_t) source->rows; y++)
{
  p=GetVirtualPixels(source,0,y,source->columns,1,exception);
  q=GetAuthenticPixels(destination,0,y,destination->columns,1,exception);
  if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL)
    break;
  for (x=0; x < (ssize_t) source->columns; x++)
  {
    SetPixelRed(image,90*p->red/100,q);
    SetPixelGreen(image,90*p->green/100,q);
    SetPixelBlue(image,90*p->blue/100,q);
    SetPixelAlpha(image,90*p->opacity/100,q);
    p+=GetPixelChannels(source);
    q+=GetPixelChannels(destination);
  }
  if (SyncAuthenticPixels(destination,exception) == MagickFalse)
    break;
}
if (y < (ssize_t) source->rows)
  { /* an exception was thrown */ }

const void
  *metacontent;

for (y=0; y < (ssize_t) source->rows; y++)
{
  p=GetVirtualPixels(source,0,y,source->columns,1);
  if (p == (const Quantum *) NULL)
    break;
  metacontent=GetVirtualMetacontent(source);
  /* print meta content here */
}
if (y < (ssize_t) source->rows)
  /* an exception was thrown */

p=GetVirtualPixels(source,-3,-3,source->columns+3,6,exception);

-> identify -list resource
Resource limits:
  Width: 100MP
  Height: 100MP
  Area: 25.181GB
  Memory: 11.726GiB
  Map: 23.452GiB
  Disk: unlimited
  File: 768
  Thread: 12
  Throttle: 0
  Time: unlimited

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE policymap [
<!ELEMENT policymap (policy)*>
<!ATTLIST policymap xmlns CDATA #FIXED "">
<!ELEMENT policy EMPTY>
<!ATTLIST policy xmlns CDATA #FIXED "">
<!ATTLIST policy domain NMTOKEN #REQUIRED>
<!ATTLIST policy name NMTOKEN #IMPLIED>
<!ATTLIST policy pattern CDATA #IMPLIED>
<!ATTLIST policy rights NMTOKEN #IMPLIED>
<!ATTLIST policy stealth NMTOKEN #IMPLIED>
<!ATTLIST policy value CDATA #IMPLIED>
]>
<!--
  Creating a security policy that fits your specific local environment
  before making use of ImageMagick is highly advised. You can find guidance on
  setting up this policy at https://imagemagick.org/security-policy/,
  and it's important to verify your policy using the validation tool located
  at https://imagemagick-secevaluator.doyensec.com/.


  Secure ImageMagick security policy:

  This stringent security policy prioritizes the implementation of
  rigorous controls and restricted resource utilization to establish a
  profoundly secure setting while employing ImageMagick. It deactivates
  conceivably hazardous functionalities, including specific coders like
  SVG or HTTP. The policy promotes the tailoring of security measures to
  harmonize with the requirements of the local environment and the guidelines
  of the organization. This protocol encompasses explicit particulars like
  limitations on memory consumption, sanctioned pathways for reading and
  writing, confines on image sequences, the utmost permissible duration of
  workflows, allocation of disk space intended for image data, and even an
  undisclosed passphrase for remote connections. By adopting this robust
  policy, entities can elevate their overall security stance and alleviate
  potential vulnerabilities.
-->
<policymap>
  <!-- Set maximum parallel threads. -->
  <policy domain="resource" name="thread" value="2"/>
  <!-- Set maximum time in seconds. When this limit is exceeded, an exception
       is thrown and processing stops. -->
  <policy domain="resource" name="time" value="120"/>
  <!-- Set maximum number of open pixel cache files. When this limit is
       exceeded, any subsequent pixels cached to disk are closed and reopened
       on demand. -->
  <policy domain="resource" name="file" value="768"/>
  <!-- Set maximum amount of memory in bytes to allocate for the pixel cache
       from the heap. When this limit is exceeded, the image pixels are cached
       to memory-mapped disk. -->
  <policy domain="resource" name="memory" value="256MiB"/>
  <!-- Set maximum amount of memory map in bytes to allocate for the pixel
       cache. When this limit is exceeded, the image pixels are cached to
       disk. -->
  <policy domain="resource" name="map" value="512MiB"/>
  <!-- Set the maximum width * height of an image that can reside in the pixel
       cache memory. Images that exceed the area limit are cached to disk. -->
  <policy domain="resource" name="area" value="16KP"/>
  <!-- Set maximum amount of disk space in bytes permitted for use by the pixel
       cache. When this limit is exceeded, the pixel cache is not be created
       and an exception is thrown. -->
  <policy domain="resource" name="disk" value="1GiB"/>
  <!-- Set the maximum length of an image sequence.  When this limit is
       exceeded, an exception is thrown. -->
  <policy domain="resource" name="list-length" value="32"/>
  <!-- Set the maximum width of an image.  When this limit is exceeded, an
       exception is thrown. -->
  <policy domain="resource" name="width" value="8KP"/>
  <!-- Set the maximum height of an image.  When this limit is exceeded, an
       exception is thrown. -->
  <policy domain="resource" name="height" value="8KP"/>
  <!-- Periodically yield the CPU for at least the time specified in
       milliseconds. -->
  <!--  -->
  <!-- Do not create temporary files in the default shared directories, instead
       specify a private area to store only ImageMagick temporary files. -->
  <!--  -->
  <!-- Force memory initialization by memory mapping select memory
       allocations. -->
  <policy domain="cache" name="memory-map" value="anonymous"/>
  <!-- Ensure all image data is fully flushed and synchronized to disk. -->
  <policy domain="cache" name="synchronize" value="true"/>
  <!-- Replace passphrase for secure distributed processing -->
  <!--  -->
  <!-- Do not permit any delegates to execute. -->
  <policy domain="delegate" rights="none" pattern="*"/>
  <!-- Do not permit any image filters to load. -->
  <policy domain="filter" rights="none" pattern="*"/>
  <!-- Don't read/write from/to stdin/stdout. -->
  <policy domain="path" rights="none" pattern="-"/>
  <!-- don't read sensitive paths. -->
  <policy domain="path" rights="none" pattern="/etc/*"/>
  <!-- Indirect reads are not permitted. -->
  <policy domain="path" rights="none" pattern="@*"/>
  <!-- These image types are security risks on read, but write is fine -->
  <policy domain="module" rights="write" pattern="{MSL,MVG,PS,SVG,URL,XPS}"/>
  <!-- This policy sets the number of times to replace content of certain
       memory buffers and temporary files before they are freed or deleted. -->
  <policy domain="system" name="shred" value="1"/>
  <!-- Enable the initialization of buffers with zeros, resulting in a minor
       performance penalty but with improved security. -->
  <policy domain="system" name="memory-map" value="anonymous"/>
  <!-- Set the maximum amount of memory in bytes that is permitted for
       allocation requests. -->
  <policy domain="system" name="max-memory-request" value="256MiB"/>
</policymap>

$ magick -debug cache logo: -sharpen 3x2 null:
2016-12-17T13:33:42-05:00 0:00.000 0.000u 7.0.0 Cache magick: cache.c/DestroyPixelCache/1275/Cache
  destroy
2016-12-17T13:33:42-05:00 0:00.000 0.000u 7.0.0 Cache magick: cache.c/OpenPixelCache/3834/Cache
  open LOGO[0] (Heap Memory, 640x480x4 4.688MiB)
2016-12-17T13:33:42-05:00 0:00.010 0.000u 7.0.0 Cache magick: cache.c/OpenPixelCache/3834/Cache
  open LOGO[0] (Heap Memory, 640x480x3 3.516MiB)
2016-12-17T13:33:42-05:00 0:00.010 0.000u 7.0.0 Cache magick: cache.c/ClonePixelCachePixels/1044/Cache
  Memory => Memory
2016-12-17T13:33:42-05:00 0:00.020 0.010u 7.0.0 Cache magick: cache.c/ClonePixelCachePixels/1044/Cache
  Memory => Memory
2016-12-17T13:33:42-05:00 0:00.020 0.010u 7.0.0 Cache magick: cache.c/OpenPixelCache/3834/Cache
  open LOGO[0] (Heap Memory, 640x480x3 3.516MiB)
2016-12-17T13:33:42-05:00 0:00.050 0.100u 7.0.0 Cache magick: cache.c/DestroyPixelCache/1275/Cache
  destroy LOGO[0]
2016-12-17T13:33:42-05:00 0:00.050 0.100u 7.0.0 Cache magick: cache.c/DestroyPixelCache/1275/Cache
  destroy LOGO[0]

magick -distribute-cache 6668 &  // start on 192.168.100.50
magick -define registry:cache:hosts=192.168.100.50:6668 myimage.jpg -sharpen 5x2 mimage.png

CacheView
  *first_row,
  *last_row;

first_row=AcquireVirtualCacheView(source,exception);
last_row=AcquireVirtualCacheView(source,exception);
for (y=0; y < (ssize_t) source->rows; y++)
{
  const Quantum
    *p,
    *q;

  p=GetCacheViewVirtualPixels(first_row,0,y,source->columns,1,exception);
  q=GetCacheViewVirtualPixels(last_row,0,source->rows-y-1,source->columns,1,exception);
  if ((p == (const Quantum *) NULL) || (q == (const Quantum *) NULL))
    break;
  for (x=0; x < (ssize_t) source->columns; x++)
  {
    /* do something with p & q here */
  }
}
last_row=DestroyCacheView(last_row);
first_row=DestroyCacheView(first_row);
if (y < (ssize_t) source->rows)
  { /* an exception was thrown */ }

magick -limit memory 2GB -limit map 4GB -define registry:temporary-path=/data/tmp ...

magick image.tif image.mpc
magick image.mpc -crop 100x100+0+0 +repage 1.png
magick image.mpc -crop 100x100+100+0 +repage 2.png
magick image.mpc -crop 100x100+200+0 +repage 3.png

(void) printf("image width: %lu, height: %lu\n",image->columns,image->rows);

const char
  *comment;

(void) SetImageProperty(image,"comment","This space for rent");
comment=GetImageProperty(image,"comment");
if (comment == (const char *) NULL)
  (void) printf("Image comment: %s\n",comment);

StringInfo
  *profile;

profile=AcquireStringInfo(length);
SetStringInfoDatum(profile,my_exif_profile);
(void) SetImageProfile(image,"EXIF",profile);
DestroyStringInfo(profile);
profile=GetImageProfile(image,"EXIF");
if (profile != (StringInfo *) NULL)
  (void) PrintStringInfo(stdout,"EXIF",profile);

static size_t StreamPixels(const Image *image,const void *pixels,const size_t columns)
{
  register const Quantum
    *p;

  MyData
    *my_data;

  my_data=(MyData *) image->client_data;
  p=(Quantum *) pixels;
  if (p != (const Quantum *) NULL)
    {
      /* process pixels here */
    }
  return(columns);
}

...

/* invoke the pixel stream here */
image_info->client_data=(void *) MyData;
image=ReadStream(image_info,&StreamPixels,exception);

magick logo: -resize 250000x250000 logo.miff

magick -define registry:temporary-path=/data/tmp logo:  \   
     -resize 250000x250000 logo.miff

magick -define registry:temporary-path=/data/tmp -limit memory 16mb \
  logo: -resize 250000x250000 logo.miff

magick -define registry:temporary-path=/data/tmp -limit area 0 \
  logo: -resize 250000x250000 logo.miff

magick -monitor -limit memory 2GiB -limit map 4GiB -define registry:temporary-path=/data/tmp \
  logo: -resize 250000x250000 logo.miff

magick -distribute-cache 6668 &  // start on 192.168.100.50
magick -distribute-cache 6668 &  // start on 192.168.100.51
magick -limit memory 2mb -limit map 2mb -limit disk 2gb \
  -define registry:cache:hosts=192.168.100.50:6668,192.168.100.51:6668 \
  myhugeimage.jpg -sharpen 5x2 myhugeimage.png

CacheView
  *image_view;

MagickBooleanType
  status;

ssize_t
  y;

/*
  Acquire a cache view to enable parallelism.
*/
status=MagickTrue;
image_view=AcquireVirtualCacheView(image,exception);
#pragma omp parallel for schedule(static,4) shared(status)
for (y=0; y < (ssize_t) image->rows; y++)
{
  register Quantum
    *q;

  register ssize_t
    x;

  register void
    *metacontent;

  if (status == MagickFalse)
    continue;
  /*
    Get a row of pixels.
  */
  q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
  if (q == (Quantum *) NULL)
    {
      status=MagickFalse;
      continue;
    }
  metacontent=GetCacheViewAuthenticMetacontent(image_view);
  for (x=0; x < (ssize_t) image->columns; x++)
  {
    /*
      Set the pixel color.
    */
    SetPixelRed(image,...,q);
    SetPixelGreen(image,...,q);
    SetPixelBlue(image,...,q);
    SetPixelAlpha(image,...,q);
    if (metacontent != NULL)
      metacontent[indexes+x]=...;
    q+=GetPixelChannels(image);
  }
  /*
    Sync the updated pixels to the pixel cache.
  */
  if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
    status=MagickFalse;
}
/*
  Destroy the cache view.
*/
image_view=DestroyCacheView(image_view);
if (status == MagickFalse)
  perror("something went wrong");

#include "Magick++.h"
#include <assert.h>
#include "omp.h"

void ConvertBMPToImage(const BITMAPINFOHEADER *bmp_info,
  const unsigned char *restrict pixels,Magick::Image *image)
{
  /*
    Prepare the image so that we can modify the pixels directly.
  */
  assert(bmp_info->biCompression == BI_RGB);
  assert(bmp_info->biWidth == image->columns());
  assert(abs(bmp_info->biHeight) == image->rows());
  image->modifyImage();
  if (bmp_info->biBitCount == 24)
    image->type(MagickCore::TrueColorType);
  else
    image->type(MagickCore::TrueColorMatteType);
  register unsigned int bytes_per_row=bmp_info->biWidth*bmp_info->biBitCount/8;
  if (bytes_per_row % 4 != 0) {
    bytes_per_row=bytes_per_row+(4-bytes_per_row % 4);  // divisible by 4.
  }
  /*
    Copy all pixel data, row by row.
  */
  #pragma omp parallel for
  for (int y=0; y < int(image->rows()); y++)
  {
    int
      row;

    register const unsigned char
      *restrict p;

    register MagickCore::Quantum
      *restrict q;

    row=(bmp_info->biHeight > 0) ? (image->rows()-y-1) : y;
    p=pixels+row*bytes_per_row;
    q=image->setPixels(0,y,image->columns(),1);
    for (int x=0; x < int(image->columns()); x++)
    {
      SetPixelBlue(image,p[0],q);
      SetPixelGreen(image,p[1],q);
      SetPixelRed(image,p[2],q);
      if (bmp_info->biBitCount == 32) {
        SetPixelAlpha(image,p[3],q);
      }
      q+=GetPixelChannels(image);
      p+=bmp_info->biBitCount/8;
    }
    image->syncPixels();  // sync pixels to pixel cache.
  }
  return;
}

<policy domain="resource" name="thread" value="2"/>

export MAGICK_THREAD_LIMIT=12

$ magick -bench 10 model.png -sharpen 5x2 null:
Performance[1]: 10i 1.135ips 1.000e 8.760u 0:08.810
Performance[2]: 10i 2.020ips 0.640e 9.190u 0:04.950
Performance[3]: 10i 2.786ips 0.710e 9.400u 0:03.590
Performance[4]: 10i 3.378ips 0.749e 9.580u 0:02.960
Performance[5]: 10i 4.032ips 0.780e 9.580u 0:02.480
Performance[6]: 10i 4.566ips 0.801e 9.640u 0:02.190
Performance[7]: 10i 3.788ips 0.769e 10.980u 0:02.640
Performance[8]: 10i 4.115ips 0.784e 12.030u 0:02.430
Performance[9]: 10i 4.484ips 0.798e 12.860u 0:02.230
Performance[10]: 10i 4.274ips 0.790e 14.830u 0:02.340
Performance[11]: 10i 4.348ips 0.793e 16.500u 0:02.300
Performance[12]: 10i 4.525ips 0.799e 18.320u 0:02.210

<policy domain="resource" name="dynamic-throttle" value="true"/>

magick identify -version
Features: DPC Cipher Modules OpenCL OpenMP(4.5)

magick image.png -convolve '-1, -1, -1, -1, 9, -1, -1, -1, -1' convolve.png

static inline long ClampToCanvas(const long offset,const ulong range)
{
  if (offset < 0L)
    return(0L);
  if (offset >= range)
    return((long) (range-1L));
  return(offset);
}

static inline CLQuantum ClampToQuantum(const float value)
{
  if (value < 0.0)
    return((CLQuantum) 0);
  if (value >= (float) QuantumRange)
    return((CLQuantum) QuantumRange);
  return((CLQuantum) (value+0.5));
}

__kernel void Convolve(const __global CLPixelType *source,__constant float *filter,
  const ulong width,const ulong height,__global CLPixelType *destination)
{
  const ulong columns = get_global_size(0);
  const ulong rows = get_global_size(1);

  const long x = get_global_id(0);
  const long y = get_global_id(1);

  const float scale = (1.0/QuantumRange);
  const long mid_width = (width-1)/2;
  const long mid_height = (height-1)/2;
  float4 sum = { 0.0, 0.0, 0.0, 0.0 };
  float gamma = 0.0;
  register ulong i = 0;

  for (long v=(-mid_height); v <= mid_height; v++)
  {
    for (long u=(-mid_width); u <= mid_width; u++)
    {
      register const ulong index=ClampToCanvas(y+v,rows)*columns+ClampToCanvas(x+u,
        columns);
      const float alpha=scale*(QuantumRange-source[index].w);
      sum.x+=alpha*filter[i]*source[index].x;
      sum.y+=alpha*filter[i]*source[index].y;
      sum.z+=alpha*filter[i]*source[index].z;
      sum.w+=filter[i]*source[index].w;
      gamma+=alpha*filter[i];
      i++;
    }
  }

  gamma=1.0/(fabs(gamma) <= MagickEpsilon ? 1.0 : gamma);
  const ulong index=y*columns+x;
  destination[index].x=ClampToQuantum(gamma*sum.x);
  destination[index].y=ClampToQuantum(gamma*sum.y);
  destination[index].z=ClampToQuantum(gamma*sum.z);
  destination[index].w=ClampToQuantum(sum.w);
};

#include <MagickCore/studio.h>
#include <MagickCore/blob.h>
#include <MagickCore/cache.h>
#include <MagickCore/colorspace.h>
#include <MagickCore/exception.h>
#include <MagickCore/image.h>
#include <MagickCore/list.h>
#include <MagickCore/magick.h>
#include <MagickCore/memory_.h>
#include <MagickCore/monitor.h>
#include <MagickCore/pixel-accessor.h>
#include <MagickCore/string_.h>
#include <MagickCore/module.h>
#include "filter/blob-private.h"
#include "filter/exception-private.h"
#include "filter/image-private.h"
#include "filter/monitor-private.h"
#include "filter/quantum-private.h"

/*
  Forward declarations.
*/
static MagickBooleanType
  WriteMGKImage(const ImageInfo *,Image *,ExceptionInfo *);

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   I s M G K                                                                 %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  IsMGK() returns MagickTrue if the image format type, identified by the
%  magick string, is MGK.
%
%  The format of the IsMGK method is:
%
%      MagickBooleanType IsMGK(const unsigned char *magick,const size_t length)
%
%  A description of each parameter follows:
%
%    o magick: This string is generally the first few bytes of an image file
%      or blob.
%
%    o length: Specifies the length of the magick string.
%
*/
static MagickBooleanType IsMGK(const unsigned char *magick,const size_t length)
{
  if (length < 7)
    return(MagickFalse);
  if (LocaleNCompare((char *) magick,"id=mgk",7) == 0)
    return(MagickTrue);
  return(MagickFalse);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   R e a d M G K I m a g e                                                   %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  ReadMGKImage() reads a MGK image file and returns it.  It allocates the
%  memory necessary for the new Image structure and returns a pointer to the
%  new image.
%
%  The format of the ReadMGKImage method is:
%
%      Image *ReadMGKImage(const ImageInfo *image_info,
%        ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image_info: the image info.
%
%    o exception: return any errors or warnings in this structure.
%
*/
static Image *ReadMGKImage(const ImageInfo *image_info,ExceptionInfo *exception)
{
  char
    buffer[MaxTextExtent];

  Image
    *image;

  long
    y;

  MagickBooleanType
    status;

  register long
    x;

  register Quantum
    *q;

  register unsigned char
    *p;

  ssize_t
    count;

  unsigned char
    *pixels;

  unsigned long
    columns,
    rows;

  /*
    Open image file.
  */
  assert(image_info != (const ImageInfo *) NULL);
  assert(image_info->signature == MagickCoreSignature);
  if (image_info->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
      image_info->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickCoreSignature);
  image=AcquireImage(image_info,exception);
  status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
  if (status == MagickFalse)
    {
      image=DestroyImageList(image);
      return((Image *) NULL);
    }
  /*
    Read MGK image.
  */
  (void) ReadBlobString(image,buffer);  /* read magic number */
  if (IsMGK(buffer,7) == MagickFalse)
    ThrowReaderException(CorruptImageError,"ImproperImageHeader");
  (void) ReadBlobString(image,buffer);
  count=(ssize_t) sscanf(buffer,"%lu %lu\n",&columns,&rows);
  if (count <= 0)
    ThrowReaderException(CorruptImageError,"ImproperImageHeader");
  do
  {
    /*
      Initialize image structure.
    */
    image->columns=columns;
    image->rows=rows;
    image->depth=8;
    if ((image_info->ping != MagickFalse) && (image_info->number_scenes != 0))
      if (image->scene >= (image_info->scene+image_info->number_scenes-1))
        break;
    /*
      Convert MGK raster image to pixel packets.
    */
    if (SetImageExtent(image,image->columns,image->rows,exception) == MagickFalse)
      return(DestroyImageList(image));
    pixels=(unsigned char *) AcquireQuantumMemory((size_t) image->columns,
      3UL*sizeof(*pixels));
    if (pixels == (unsigned char *) NULL)
      ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
    for (y=0; y < (long) image->rows; y++)
    {
      count=(ssize_t) ReadBlob(image,(size_t) (3*image->columns),pixels);
      if (count != (ssize_t) (3*image->columns))
        ThrowReaderException(CorruptImageError,"UnableToReadImageData");
      p=pixels;
      q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
      if (q == (Quantum *) NULL)
        break;
      for (x=0; x < (long) image->columns; x++)
      {
        SetPixelRed(image,ScaleCharToQuantum(*p++),q);
        SetPixelGreen(image,ScaleCharToQuantum(*p++),q);
        SetPixelBlue(image,ScaleCharToQuantum(*p++),q);
        q+=GetPixelChannels(image);
      }
      if (SyncAuthenticPixels(image,exception) == MagickFalse)
        break;
      if (image->previous == (Image *) NULL)
        if ((image->progress_monitor != (MagickProgressMonitor) NULL) &&
            (QuantumTick(y,image->rows) != MagickFalse))
          {
            status=image->progress_monitor(LoadImageTag,y,image->rows,
              image->client_data);
            if (status == MagickFalse)
              break;
          }
    }
    pixels=(unsigned char *) RelinquishMagickMemory(pixels);
    if (EOFBlob(image) != MagickFalse)
      {
        ThrowFileException(exception,CorruptImageError,"UnexpectedEndOfFile",
          image->filename);
        break;
      }
    /*
      Proceed to next image.
    */
    if (image_info->number_scenes != 0)
      if (image->scene >= (image_info->scene+image_info->number_scenes-1))
        break;
    *buffer='\0';
    (void) ReadBlobString(image,buffer);
    count=(ssize_t) sscanf(buffer,"%lu %lu\n",&columns,&rows);
    if (count > 0)
      {
        /*
          Allocate next image structure.
        */
        AcquireNextImage(image_info,image,exception);
        if (GetNextImageInList(image) == (Image *) NULL)
          {
            image=DestroyImageList(image);
            return((Image *) NULL);
          }
        image=SyncNextImageInList(image);
        if (image->progress_monitor != (MagickProgressMonitor) NULL)
          {
            status=SetImageProgress(image,LoadImageTag,TellBlob(image),
              GetBlobSize(image));
            if (status == MagickFalse)
              break;
          }
      }
  } while (count > 0);
  (void) CloseBlob(image);
  return(GetFirstImageInList(image));
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   R e g i s t e r M G K I m a g e                                           %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  RegisterMGKImage() adds attributes for the MGK image format to
%  the list of supported formats.  The attributes include the image format
%  tag, a method to read and/or write the format, whether the format
%  supports the saving of more than one frame to the same file or blob,
%  whether the format supports native in-memory I/O, and a brief
%  description of the format.
%
%  The format of the RegisterMGKImage method is:
%
%      unsigned long RegisterMGKImage(void)
%
*/
ModuleExport unsigned long RegisterMGKImage(void)
{
  MagickInfo
    *entry;

  entry=AcquireMagickInfo("MGK","MGK","MGK image");
  entry->decoder=(DecodeImageHandler *) ReadMGKImage;
  entry->encoder=(EncodeImageHandler *) WriteMGKImage;
  entry->magick=(IsImageFormatHandler *) IsMGK;
  (void) RegisterMagickInfo(entry);
  return(MagickImageCoderSignature);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   U n r e g i s t e r M G K I m a g e                                       %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  UnregisterMGKImage() removes format registrations made by the
%  MGK module from the list of supported formats.
%
%  The format of the UnregisterMGKImage method is:
%
%      UnregisterMGKImage(void)
%
*/
ModuleExport void UnregisterMGKImage(void)
{
  (void) UnregisterMagickInfo("MGK");
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   W r i t e M G K I m a g e                                                 %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  WriteMGKImage() writes an image to a file in red, green, and blue MGK
%  rasterfile format.
%
%  The format of the WriteMGKImage method is:
%
%      MagickBooleanType WriteMGKImage(const ImageInfo *image_info,
%        Image *image)
%
%  A description of each parameter follows.
%
%    o image_info: the image info.
%
%    o image:  The image.
%
%    o exception:  return any errors or warnings in this structure.
%
*/
static MagickBooleanType WriteMGKImage(const ImageInfo *image_info,Image *image,
  ExceptionInfo *exception)
{
  char
    buffer[MaxTextExtent];

  long
    y;

  MagickBooleanType
    status;

  MagickOffsetType
    scene;

  register const Quantum
    *p;

  register long
    x;

  register unsigned char
    *q;

  unsigned char
    *pixels;

  /*
    Open output image file.
  */
  assert(image_info != (const ImageInfo *) NULL);
  assert(image_info->signature == MagickCoreSignature);
  assert(image != (Image *) NULL);
  assert(image->signature == MagickCoreSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  status=OpenBlob(image_info,image,WriteBinaryBlobMode,exception);
  if (status == MagickFalse)
    return(status);
  scene=0;
  do
  {
    /*
      Allocate memory for pixels.
    */
    if (image->colorspace != RGBColorspace)
      (void) SetImageColorspace(image,RGBColorspace,exception);
    pixels=(unsigned char *) AcquireQuantumMemory((size_t) image->columns,
      3UL*sizeof(*pixels));
    if (pixels == (unsigned char *) NULL)
      ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
    /*
      Initialize raster file header.
    */
    (void) WriteBlobString(image,"id=mgk\n");
    (void) FormatLocaleString(buffer,MaxTextExtent,"%lu %lu\n",image->columns,
       image->rows);
    (void) WriteBlobString(image,buffer);
    for (y=0; y < (long) image->rows; y++)
    {
      p=GetVirtualPixels(image,0,y,image->columns,1,exception);
      if (p == (const Quantum *) NULL)
        break;
      q=pixels;
      for (x=0; x < (long) image->columns; x++)
      {
        *q++=ScaleQuantumToChar(GetPixelRed(image,p));
        *q++=ScaleQuantumToChar(GetPixelGreen(image,p));
        *q++=ScaleQuantumToChar(GetPixelBlue(image,p));
        p+=GetPixelChannels(image);
      }
      (void) WriteBlob(image,(size_t) (q-pixels),pixels);
      if (image->previous == (Image *) NULL)
        if ((image->progress_monitor != (MagickProgressMonitor) NULL) &&
            (QuantumTick(y,image->rows) != MagickFalse))
          {
            status=image->progress_monitor(SaveImageTag,y,image->rows,
              image->client_data);
            if (status == MagickFalse)
              break;
          }
    }
    pixels=(unsigned char *) RelinquishMagickMemory(pixels);
    if (GetNextImageInList(image) == (Image *) NULL)
      break;
    image=SyncNextImageInList(image);
    status=SetImageProgress(image,SaveImagesTag,scene,
      GetImageListLength(image));
    if (status == MagickFalse)
      break;
    scene++;
  } while (image_info->adjoin != MagickFalse);
  (void) CloseBlob(image);
  return(MagickTrue);
}

magick logo: logo.mgk
display logo.mgk

export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <assert.h>
#include <math.h>
#include "MagickCore/studio.h"
#include "MagickCore/MagickCore.h"

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   a n a l y z e I m a g e                                                   %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  analyzeImage() computes the brightness and saturation mean,  standard
%  deviation, kurtosis and skewness and stores these values as attributes
%  of the image.
%
%  The format of the analyzeImage method is:
%
%      size_t analyzeImage(Image *images,const int argc,char **argv,
%        ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o image: the address of a structure of type Image.
%
%    o argc: Specifies a pointer to an integer describing the number of
%      elements in the argument vector.
%
%    o argv: Specifies a pointer to a text array containing the command line
%      arguments.
%
%    o exception: return any errors or warnings in this structure.
%
*/

typedef struct _StatisticsInfo
{
  double
    area,
    brightness,
    mean,
    standard_deviation,
    sum[5],
    kurtosis,
    skewness;
} StatisticsInfo;

static inline int GetMagickNumberThreads(const Image *source,
  const Image *destination,const size_t chunk,int multithreaded)
{
#define MagickMax(x,y)  (((x) > (y)) ? (x) : (y))
#define MagickMin(x,y)  (((x) < (y)) ? (x) : (y))

  /*
    Number of threads bounded by the amount of work and any thread resource
    limit.  The limit is 2 if the pixel cache type is not memory or
    memory-mapped.
  */
  if (multithreaded == 0)
    return(1);
  if (((GetImagePixelCacheType(source) != MemoryCache) &&
       (GetImagePixelCacheType(source) != MapCache)) ||
      ((GetImagePixelCacheType(destination) != MemoryCache) &&
       (GetImagePixelCacheType(destination) != MapCache)))
    return(MagickMax(MagickMin(GetMagickResourceLimit(ThreadResource),2),1));
  return(MagickMax(MagickMin((ssize_t) GetMagickResourceLimit(ThreadResource),
    (ssize_t) (chunk)/64),1));
}

ModuleExport size_t analyzeImage(Image **images,const int argc,
  const char **argv,ExceptionInfo *exception)
{
#define AnalyzeImageFilterTag  "Filter/Analyze"
#define magick_number_threads(source,destination,chunk,multithreaded) \
  num_threads(GetMagickNumberThreads(source,destination,chunk,multithreaded))

  char
    text[MagickPathExtent];

  Image
    *image;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  assert(images != (Image **) NULL);
  assert(*images != (Image *) NULL);
  assert((*images)->signature == MagickCoreSignature);
  (void) argc;
  (void) argv;
  status=MagickTrue;
  progress=0;
  for (image=(*images); image != (Image *) NULL; image=GetNextImageInList(image))
  {
    CacheView
      *image_view;

    double
      area;

    ssize_t
      y;

    StatisticsInfo
      brightness,
      saturation;

    if (status == MagickFalse)
      continue;
    (void) memset(&brightness,0,sizeof(brightness));
    (void) memset(&saturation,0,sizeof(saturation));
    status=MagickTrue;
    image_view=AcquireVirtualCacheView(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(static) \
    shared(progress,status,brightness,saturation) \
    magick_number_threads(image,image,image->rows,1)
#endif
    for (y=0; y < (ssize_t) image->rows; y++)
    {
      const Quantum
        *p;

      ssize_t
        i,
        x;

      StatisticsInfo
        local_brightness,
        local_saturation;

      if (status == MagickFalse)
        continue;
      p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
      if (p == (const Quantum *) NULL)
        {
          status=MagickFalse;
          continue;
        }
      (void) memset(&local_brightness,0,sizeof(local_brightness));
      (void) memset(&local_saturation,0,sizeof(local_saturation));
      for (x=0; x < (ssize_t) image->columns; x++)
      {
        double
          b,
          h,
          s;

        ConvertRGBToHSL(GetPixelRed(image,p),GetPixelGreen(image,p),
          GetPixelBlue(image,p),&h,&s,&b);
        b*=QuantumRange;
        for (i=1; i <= 4; i++)
          local_brightness.sum[i]+=pow(b,(double) i);
        s*=QuantumRange;
        for (i=1; i <= 4; i++)
          local_saturation.sum[i]+=pow(s,(double) i);
        p+=GetPixelChannels(image);
      }
#if defined(MAGICKCORE_OPENMP_SUPPORT)
      #pragma omp critical (analyzeImage)
#endif
      for (i=1; i <= 4; i++)
      {
        brightness.sum[i]+=local_brightness.sum[i];
        saturation.sum[i]+=local_saturation.sum[i];
      }
    }
    image_view=DestroyCacheView(image_view);
    area=(double) image->columns*image->rows;
    brightness.mean=brightness.sum[1]/area;
    (void) FormatLocaleString(text,MagickPathExtent,"%g",brightness.mean);
    (void) SetImageProperty(image,"filter:brightness:mean",text,exception);
    brightness.standard_deviation=sqrt(brightness.sum[2]/area-
      (brightness.sum[1]/area*brightness.sum[1]/area));
    (void) FormatLocaleString(text,MagickPathExtent,"%g",
      brightness.standard_deviation);
    (void) SetImageProperty(image,"filter:brightness:standard-deviation",text,
      exception);
    if (fabs(brightness.standard_deviation) >= MagickEpsilon)
      brightness.kurtosis=(brightness.sum[4]/area-4.0*brightness.mean*
        brightness.sum[3]/area+6.0*brightness.mean*brightness.mean*
        brightness.sum[2]/area-3.0*brightness.mean*brightness.mean*
        brightness.mean*brightness.mean)/(brightness.standard_deviation*
        brightness.standard_deviation*brightness.standard_deviation*
        brightness.standard_deviation)-3.0;
    (void) FormatLocaleString(text,MagickPathExtent,"%g",brightness.kurtosis);
    (void) SetImageProperty(image,"filter:brightness:kurtosis",text,exception);
    if (brightness.standard_deviation != 0)
      brightness.skewness=(brightness.sum[3]/area-3.0*brightness.mean*
        brightness.sum[2]/area+2.0*brightness.mean*brightness.mean*
        brightness.mean)/(brightness.standard_deviation*
        brightness.standard_deviation*brightness.standard_deviation);
    (void) FormatLocaleString(text,MagickPathExtent,"%g",brightness.skewness);
    (void) SetImageProperty(image,"filter:brightness:skewness",text,exception);
    saturation.mean=saturation.sum[1]/area;
    (void) FormatLocaleString(text,MagickPathExtent,"%g",saturation.mean);
    (void) SetImageProperty(image,"filter:saturation:mean",text,exception);
    saturation.standard_deviation=sqrt(saturation.sum[2]/area-
      (saturation.sum[1]/area*saturation.sum[1]/area));
    (void) FormatLocaleString(text,MagickPathExtent,"%g",
      saturation.standard_deviation);
    (void) SetImageProperty(image,"filter:saturation:standard-deviation",text,
      exception);
    if (fabs(saturation.standard_deviation) >= MagickEpsilon)
      saturation.kurtosis=(saturation.sum[4]/area-4.0*saturation.mean*
        saturation.sum[3]/area+6.0*saturation.mean*saturation.mean*
        saturation.sum[2]/area-3.0*saturation.mean*saturation.mean*
        saturation.mean*saturation.mean)/(saturation.standard_deviation*
        saturation.standard_deviation*saturation.standard_deviation*
        saturation.standard_deviation)-3.0;
    (void) FormatLocaleString(text,MagickPathExtent,"%g",saturation.kurtosis);
    (void) SetImageProperty(image,"filter:saturation:kurtosis",text,exception);
    if (fabs(saturation.standard_deviation) >= MagickEpsilon)
      saturation.skewness=(saturation.sum[3]/area-3.0*saturation.mean*
        saturation.sum[2]/area+2.0*saturation.mean*saturation.mean*
        saturation.mean)/(saturation.standard_deviation*
        saturation.standard_deviation*saturation.standard_deviation);
    (void) FormatLocaleString(text,MagickPathExtent,"%g",saturation.skewness);
    (void) SetImageProperty(image,"filter:saturation:skewness",text,exception);
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
        #pragma omp atomic
#endif
        progress++;
        proceed=SetImageProgress(image,AnalyzeImageFilterTag,progress,
          GetImageListLength(image));
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  return(MagickImageFilterSignature);
}