Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with
or
.
Download ZIP
A program that compares two images using a perceptually based image metric.
C++ CMake Shell
branch: master

Clean up

latest commit c180beba4a
@myint authored
Failed to load latest commit information.
test Make variable read-only
.clang-format Allow more whitespace
.clang_complete Enable "clang_complete"
.gitignore Update for dSYM directory.
.syntastic_cpp_config Enable OpenMP
.travis.yml Use normal cpp-coveralls
CMakeLists.txt Use consistent casing
FindFreeImage.cmake Changed cmake to find freeimage automatically
LICENSE Move to the correct place
README.rst Format
compare_args.cpp Undo a signature change of "main()"
compare_args.h Undo a signature change of "main()"
coverage.bash Move common code to "coverage.bash"
coveralls.bash
coverity.bash Document
lpyramid.cpp Clean up
lpyramid.h Undo unnecessary usage of const in declarations
memcheck.bash Track origins of memory errors
memcheck.supp Suppress false positive from FreeImage
metric.cpp More effective by move some temp array into loop so just need one tem…
metric.h Increment copyright date
perceptualdiff.cpp Undo a signature change of "main()"
rgba_image.cpp Increment copyright date
rgba_image.h

README.rst

perceptualdiff

A program that compares two images using a perceptually based image metric.

Build status Static analysis status

Copyright (C) 2006-2011 Yangli Hector Yee

Copyright (C) 2011-2015 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 file LICENSE.

Build Instructions

  1. Download CMake from http://www.cmake.org if you do not already have it on your system.

  2. 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
  3. Type:

    $ cmake .
    
  4. Type:

    $ make
    
  5. To specify the install directory, use:

    $ make install DESTDIR="/home/me/mydist"
    

Usage

Command line:

Usage: peceptualdiff 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)
  --luminanceonly  Only consider luminance; ignore chroma (color) in the
                   comparison
  --colorfactor    How much of color to use [0.0, 1.0] (default: 1.0)
  --downsample     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

Check that perceptualdiff is built with OpenMP support:

$ ./perceptualdiff | grep -i openmp
OpenMP status: enabled

Credits

  • 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.

Version History

  • 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.

Links

Something went wrong with that request. Please try again.