MagickCore, C API: Colormap Methods @ ImageMagick
Author: ImageMagick Studio LLC
Description: Use ImageMagick® to create, edit, compose, convert bitmap images. With ImageMagick you can resize your image, crop it, change its shades and colors, add captions, among other operations.
Keywords: magickcore, c, api:, colormap, methods, ImageMagick, PerlMagick, image processing, image, photo, software, Magick++, OpenMP, convert

AcquireImageColormap • CycleColormap

## AcquireImageColormap

AcquireImageColormap() allocates an image colormap and initializes it to a linear gray colorspace. If the image already has a colormap, it is replaced. AcquireImageColormap() returns MagickTrue if successful, otherwise MagickFalse if there is not enough memory.

The format of the AcquireImageColormap method is:

    MagickBooleanType AcquireImageColormap(Image *image,const size_t colors,
      ExceptionInfo *exception)

A description of each parameter follows:

image
  the image.
colors
  the number of colors in the image colormap.
exception
  return any errors or warnings in this structure.

## CycleColormap

CycleColormap() displaces an image's colormap by a given number of positions. If you cycle the colormap a number of times you can produce a psychodelic effect.

WARNING: this assumes an images colormap is in a well know and defined order. Currently Imagemagick has no way of setting that order.

The format of the CycleColormapImage method is:

    MagickBooleanType CycleColormapImage(Image *image,const ssize_t displace,
      ExceptionInfo *exception)

A description of each parameter follows:

image
  the image.
displace
  displace the colormap this amount.
exception
  return any errors or warnings in this structure.