A program that compares two images using a perceptually based image metric.
Copyright (C) 2006-2011 Yangli Hector Yee
Copyright (C) 2011-2016 Steven Myint, Jeff Terrace
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE. See the GNU General Public License for more details in the
Download CMake from http://www.cmake.org if you do not already have it on your system.
- Download FreeImage from https://sourceforge.net/projects/freeimage.
- On OS X with MacPorts:
port install freeimage
- On OS X with Brew:
brew install freeimage
- On Ubuntu:
apt-get install libfreeimage-dev
- On OS X with MacPorts:
$ cmake .
To specify the install directory, use:
$ make install DESTDIR="/home/me/mydist"
Usage: perceptualdiff image1 image2 Compares image1 and image2 using a perceptually based image metric. Options: --verbose Turn on verbose mode --fov deg Field of view in degrees [0.1, 89.9] (default: 45.0) --threshold p Number of pixels p below which differences are ignored --gamma g Value to convert rgb into linear space (default: 2.2) --luminance l White luminance (default: 100.0 cdm^-2) --luminance-only Only consider luminance; ignore chroma (color) in the comparison --color-factor How much of color to use [0.0, 1.0] (default: 1.0) --down-sample How many powers of two to down sample the image (default: 0) --scale Scale images to match each other's dimensions --sum-errors Print a sum of the luminance and color differences --output o Write difference to the file o --version Print version
Check that perceptualdiff is built with OpenMP support:
$ ./perceptualdiff | grep -i openmp OpenMP status: enabled
- Hector Yee, project administrator and originator - hectorgon.blogspot.com.
- Scott Corley, for png file IO code.
- Tobias Sauerwein, for make install, package_source Cmake configuration.
- Cairo Team, for bugfixes.
- Jim Tilander, rewrote the IO to use FreeImage.
- Steven Myint, for OpenMP support and bug fixes.
- Jeff Terrace, for better FreeImage support and new command-line options.
- 1.0 - Initial distribution
- 1.0.1 - Fixed off by one convolution error and libpng interface to 1.2.8
- 1.0.2 - [jt] Converted the loading and saving routines to use FreeImage
- 1.1 - Added colorfactor and downsample options. Also always output difference file if requested. Always print out differing pixels even if the test passes.
- 1.1.1 - Turn off color test in low lighting conditions.
- 1.1.2 - Add OpenMP parallel processing support and fix bugs.
- 1.2 - Add
--sum-errors, use more standard option style, and fix bugs.
- 1.3 - Add MSVC compatibility.
- 1.4 - Detect differences due to the alpha channel. This was lost in 1.0.2 when FreeImage was introduced.
- 2.0 - Support usage as a library.
- 2.1 - Allow accessing stats directly when used as a library.