This folder contains libraries and headers of a few very popular still image codecs used by imgcodecs module. The libraries and headers are preferably to build Win32 and Win64 versions of OpenCV. On UNIX systems all the libraries are automatically detected by configure script. In order to use these versions of libraries instead of system ones on UNIX systems you should use BUILD_ CMake flags (for example, BUILD_PNG for the libpng library). ------------------------------------------------------------------------------------ libjpeg (deprecated) The Independent JPEG Group's JPEG software. Copyright (C) 1991-2012, Thomas G. Lane, Guido Vollbeding. See IGJ home page http://www.ijg.org for details and links to the source code libjpeg-turbo libjpeg-turbo is covered by three compatible BSD-style open source licenses. Refer to [LICENSE.md](libjpeg-turbo/LICENSE.md) for a roll-up of license terms. Site: https://github.com/libjpeg-turbo/libjpeg-turbo API is compatible with original libjpeg. WITH_JPEG CMake option must be ON to add libjpeg or libjpeg-turbo support to imgcodecs. BUILD_JPEG=ON selects libjpeg-turbo by default (since OpenCV 3.4.2). Enable BUILD_JPEG_TURBO_DISABLE=ON to force using of libjpeg (this option is removed in OpenCV 4.0). SIMD instructions are enabled by default. Use ENABLE_LIBJPEG_TURBO_SIMD to control SIMD instructions. ------------------------------------------------------------------------------------ libpng Portable Network Graphics library. The license and copyright notes can be found in libpng/LICENSE. See libpng home page http://www.libpng.org for details and links to the source code WITH_PNG CMake option must be ON to add libpng support to imgcodecs. libspng Portable Network Graphics library. The license and copyright notes can be found in libspng/LICENSE. See libspng home page https://www.libspng.org for details and links to the source code WITH_SPNG CMake option must be ON to add libspng support to imgcodecs ------------------------------------------------------------------------------------ libtiff Tag Image File Format (TIFF) Software Copyright (c) 1988-1997 Sam Leffler Copyright (c) 1991-1997 Silicon Graphics, Inc. See libtiff home page http://www.libtiff.org/ for details and links to the source code WITH_TIFF CMake option must be ON to add libtiff & zlib support to imgcodecs. ------------------------------------------------------------------------------------ zlib General purpose LZ77 compression library Copyright (C) 1995-2022 Jean-loup Gailly and Mark Adler. See zlib home page http://www.zlib.net for details and links to the source code ------------------------------------------------------------------------------------ jasper JasPer is a collection of software (i.e., a library and application programs) for the coding and manipulation of images. This software can handle image data in a variety of formats. One such format supported by JasPer is the JPEG-2000 format defined in ISO/IEC 15444-1. Copyright (c) 1999-2000 Image Power, Inc. Copyright (c) 1999-2000 The University of British Columbia Copyright (c) 2001-2003 Michael David Adams See JasPer official GitHub repository https://github.com/jasper-software/jasper.git for details and links to source code ------------------------------------------------------------------------------------ openexr OpenEXR is a high dynamic-range (HDR) image file format developed by Industrial Light & Magic for use in computer imaging applications. Copyright (c) 2006, Industrial Light & Magic, a division of Lucasfilm Entertainment Company Ltd. Portions contributed and copyright held by others as indicated. All rights reserved. The project homepage: http://www.openexr.com ------------------------------------------------------------------------------------ ffmpeg FFmpeg is a complete, cross-platform solution to record, convert and stream audio and video. It includes libavcodec - the leading audio/video codec library, and also libavformat, libavutils and other helper libraries that are used by OpenCV (in videoio module) to read and write video files. Copyright (c) 2001 Fabrice Bellard The project homepage: http://ffmpeg.org/. * On Linux/OSX we link user-installed ffmpeg (or ffmpeg fork libav). * On Windows we use pre-built ffmpeg binaries, see opencv/3rdparty/ffmpeg/readme.txt for details and licensing information ------------------------------------------------------------------------------------