___ ____ _ _ _ |_ _|_ __ ___ __ _ __ _ ___ _ _ / ___|(_)_ __ ___ (_) | __ _ _ __ | || '_ ` _ \ / _` |/ _` |/ _ \ (_|_) \___ \| | '_ ` _ \| | |/ _` | '__| | || | | | | | (_| | (_| | __/ _ _ ___) | | | | | | | | | (_| | | |___|_| |_| |_|\__,_|\__, |\___| (_|_) |____/|_|_| |_| |_|_|_|\__,_|_| |___/ This is the README for Image::Similar version 0.07. Image::Similar is a "module" for the Perl computer programming language, a library of computer code to install on a computer. This document contains four sections: 1. About - what the module does 2. Documentation - how to learn more about the module 3. Installation - how to install this module on a computer 4. Help - what to do if you get stuck ----------------------------------------------------------------------------- 1. ABOUT Image::Similar - find out how similar two images are This is an experimental module for comparing images. It uses a simplified form of the algorithm described in "An image signature for any kind of image" to calculate image signatures and distances between images. The algorithm consists of converting the image into greyscale, chopping it into a grid, and then computing a signature based on relative lightness and darkness of the blocks of the grid. The module does not contain its own image-reading facility, so images must be loaded to the module via one of the following supported Perl modules: "Imager" (recommended) All image types are supported. If you have no preference, I suggest using Imager, since it is a very well-behaved module. The conversion to greyscale is done using Imager's own routines. "GD" All image types are supported. RGB images are combined to greyscale using constants taken from the source code of "Imager". "Image::Imlib2" All image types are supported. RGB images are combined to greyscale using constants taken from the source code of "Imager". "Image::PNG::Libpng" This module is used for some internals of Image::Similar related to testing, thus it was installed when you installed Image::Similar. However, Image::PNG::Libpng is only for PNG images. Image::Similar supports all PNG image types. It currently only supports bit depths of eight. RGB images are combined to greyscale using constants taken from the source code of "Imager". As of this version, there is no handling of the alpha channel (transparent pixels) and the background value is ignored. Use "load_image" to load the image. ----------------------------------------------------------------------------- 2. DOCUMENTATION You can read the documentation for the module online at the following websites: * http://search.cpan.org/perldoc?Image::Similar * http://metacpan.org/release/Image-Similar (These links go to the latest version of the module.) After installing the module, you can read the documentation on your computer using perldoc Image::Similar ----------------------------------------------------------------------------- 3. INSTALLATION This module requires Perl version 5.6.1 or later. To install the module from CPAN, use cpan Image::Similar If you have the App::cpanminus installer, you may prefer cpanm Image::Similar To install the module from the source file, Image-Similar-0.07.tar.gz, follow this sequence of commands: tar xfz Image-Similar-0.07.tar.gz cd Image-Similar-0.07 perl Makefile.PL make make install If you want to test the module before installing it, use "make test" after "make" and before "make install". ----------------------------------------------------------------------------- 4. HELP To get help with the module, you can email the author, Ben Bullock, at . If you think there is a problem in the module, you can report a bug at , or if you want to alter the source code of Image::Similar, try the public repository on github at . ----------------------------------------------------------------------------- This README was written on Sat Jul 15 16:00:52 2017. -----------------------------------------------------------------------------