G'MIC - GREYC's Magic for Image Computing: A Full-Featured Open-Source Framework for Image Processing
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A Full-Featured Open-Source Framework for Image Processing

Latest stable version: 3.6.1 (2025/08/26)

Reference
Table of Contents  ▸  List of Commands  ▸  Colors  ▸  contrast◀  compose_channels    |    count_colors  ▶

contrast

Arguments:

  • strength

Description:

Change contrast of selected images, with specified strength.
If strength is positive, image contrast is amplified.
If strength is negative, image contrast is reduced.
A typical value range for parameter strength is [-100,100].

Example of use:

image.jpg +contrast 20

Command: image.jpg +contrast 20
Command: image.jpg +contrast 20
G'MIC - GREYC's Magic for Image Computing: A Full-Featured Open-Source Framework for Image Processing

G'MIC is an open-source software distributed under the CeCILL free software licenses (LGPL-like and/or
GPL-compatible). Copyrights (C) Since July 2008, David Tschumperlé - GREYC UMR CNRS 6072, Image Team.