1libjpeg-turbo Licenses 2====================== 3 4libjpeg-turbo is covered by three compatible BSD-style open source licenses: 5 6- The IJG (Independent JPEG Group) License, which is listed in 7 [README.ijg](README.ijg) 8 9 This license applies to the libjpeg API library and associated programs 10 (any code inherited from libjpeg, and any modifications to that code.) 11 12- The Modified (3-clause) BSD License, which is listed below 13 14 This license covers the TurboJPEG API library and associated programs, as 15 well as the build system. 16 17- The [zlib License](https://opensource.org/licenses/Zlib) 18 19 This license is a subset of the other two, and it covers the libjpeg-turbo 20 SIMD extensions. 21 22 23Complying with the libjpeg-turbo Licenses 24========================================= 25 26This section provides a roll-up of the libjpeg-turbo licensing terms, to the 27best of our understanding. 28 291. If you are distributing a modified version of the libjpeg-turbo source, 30 then: 31 32 1. You cannot alter or remove any existing copyright or license notices 33 from the source. 34 35 **Origin** 36 - Clause 1 of the IJG License 37 - Clause 1 of the Modified BSD License 38 - Clauses 1 and 3 of the zlib License 39 40 2. You must add your own copyright notice to the header of each source 41 file you modified, so others can tell that you modified that file (if 42 there is not an existing copyright header in that file, then you can 43 simply add a notice stating that you modified the file.) 44 45 **Origin** 46 - Clause 1 of the IJG License 47 - Clause 2 of the zlib License 48 49 3. You must include the IJG README file, and you must not alter any of the 50 copyright or license text in that file. 51 52 **Origin** 53 - Clause 1 of the IJG License 54 552. If you are distributing only libjpeg-turbo binaries without the source, or 56 if you are distributing an application that statically links with 57 libjpeg-turbo, then: 58 59 1. Your product documentation must include a message stating: 60 61 This software is based in part on the work of the Independent JPEG 62 Group. 63 64 **Origin** 65 - Clause 2 of the IJG license 66 67 2. If your binary distribution includes or uses the TurboJPEG API, then 68 your product documentation must include the text of the Modified BSD 69 License (see below.) 70 71 **Origin** 72 - Clause 2 of the Modified BSD License 73 743. You cannot use the name of the IJG or The libjpeg-turbo Project or the 75 contributors thereof in advertising, publicity, etc. 76 77 **Origin** 78 - IJG License 79 - Clause 3 of the Modified BSD License 80 814. The IJG and The libjpeg-turbo Project do not warrant libjpeg-turbo to be 82 free of defects, nor do we accept any liability for undesirable 83 consequences resulting from your use of the software. 84 85 **Origin** 86 - IJG License 87 - Modified BSD License 88 - zlib License 89 90 91The Modified (3-clause) BSD License 92=================================== 93 94Copyright (C)2009-2021 D. R. Commander. All Rights Reserved.<br> 95Copyright (C)2015 Viktor Szathmáry. All Rights Reserved. 96 97Redistribution and use in source and binary forms, with or without 98modification, are permitted provided that the following conditions are met: 99 100- Redistributions of source code must retain the above copyright notice, 101 this list of conditions and the following disclaimer. 102- Redistributions in binary form must reproduce the above copyright notice, 103 this list of conditions and the following disclaimer in the documentation 104 and/or other materials provided with the distribution. 105- Neither the name of the libjpeg-turbo Project nor the names of its 106 contributors may be used to endorse or promote products derived from this 107 software without specific prior written permission. 108 109THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS", 110AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 111IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 112ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE 113LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 114CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 115SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 116INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 117CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 118ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 119POSSIBILITY OF SUCH DAMAGE. 120 121 122Why Three Licenses? 123=================== 124 125The zlib License could have been used instead of the Modified (3-clause) BSD 126License, and since the IJG License effectively subsumes the distribution 127conditions of the zlib License, this would have effectively placed 128libjpeg-turbo binary distributions under the IJG License. However, the IJG 129License specifically refers to the Independent JPEG Group and does not extend 130attribution and endorsement protections to other entities. Thus, it was 131desirable to choose a license that granted us the same protections for new code 132that were granted to the IJG for code derived from their software. 133