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class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Low-bitrate speech encoding format</div> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox vevent"><caption class="infobox-title summary">Codec 2</caption><tbody><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Programmer" title="Programmer">Developer(s)</a></th><td class="infobox-data">David Grant Rowe</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Initial release</th><td class="infobox-data">August 25, 2010<span style="display:none"> (<span class="bday dtstart published updated itvstart">2010-08-25</span>)</span></td></tr><tr style="display: none;"><td colspan="2" class="infobox-full-data"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1257001546"></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Software_release_life_cycle" title="Software release life cycle">Stable release</a></th><td class="infobox-data"><div style="margin:0px;">1.2.0 / June 24, 2023<span class="noprint">; 17 months ago</span><span style="display:none"> (<span class="bday dtstart published updated">2023-06-24</span>)</span></div></td></tr><tr style="display:none"><td colspan="2"> </td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Repository_(version_control)" title="Repository (version control)">Repository</a></th><td class="infobox-data"><span class="url"><a rel="nofollow" class="external text" href="https://github.com/drowe67/codec2">github<wbr />.com<wbr />/drowe67<wbr />/codec2</a></span></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Written in</th><td class="infobox-data"><a href="/wiki/C99" title="C99">C99</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Computing_platform" title="Computing platform">Platform</a></th><td class="infobox-data"><a href="/wiki/Cross-platform" class="mw-redirect" title="Cross-platform">Cross-platform</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Software_categories#Categorization_approaches" title="Software categories">Type</a></th><td class="infobox-data"><a href="/wiki/Audio_codec" title="Audio codec">Audio codec</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Software_license" title="Software license">License</a></th><td class="infobox-data"><a href="/wiki/GNU_LGPL" class="mw-redirect" title="GNU LGPL">GNU LGPL</a>, v2.1</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Website</th><td class="infobox-data"><span class="url"><a rel="nofollow" class="external text" href="https://www.rowetel.com/?page_id=452">www<wbr />.rowetel<wbr />.com?page<wbr />_id=452</a></span></td></tr></tbody></table> <p><b>Codec 2</b> is a low-bitrate speech audio <a href="/wiki/Codec" title="Codec">codec</a> (<a href="/wiki/Speech_coding" title="Speech coding">speech coding</a>) that is <a href="/wiki/Patent" title="Patent">patent</a> free and <a href="/wiki/Open-source_software" title="Open-source software">open source</a>.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> Codec 2 compresses speech using <a href="/wiki/Sinusoidal" class="mw-redirect" title="Sinusoidal">sinusoidal</a> coding, a method specialized for human <a href="/wiki/Speech" title="Speech">speech</a>. Bit rates of 3200 to 450 bit/s have been successfully created. Codec 2 was designed to be used for <a href="/wiki/Amateur_radio" title="Amateur radio">amateur radio</a> and other high compression voice applications. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Overview">Overview</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Codec_2&action=edit&section=1" title="Edit section: Overview"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The codec was developed by David Grant Rowe, with support and cooperation of other researchers (e.g., Jean-Marc Valin from <a href="/wiki/Opus_(audio_format)" title="Opus (audio format)">Opus</a>).<sup id="cite_ref-jmspeex_2-0" class="reference"><a href="#cite_note-jmspeex-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>Codec 2 consists of 3200, 2400, 1600, 1400, 1300, 1200, 700 and 450 bit/s codec modes. It outperforms most other low-bitrate <a href="/wiki/Speech_coding" title="Speech coding">speech codecs</a>. For example, it uses half the bandwidth of <a href="/wiki/Advanced_Multi-Band_Excitation" class="mw-redirect" title="Advanced Multi-Band Excitation">Advanced Multi-Band Excitation</a> to encode speech with similar quality.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (September 2020)">citation needed</span></a></i>]</sup> The speech codec uses 16-bit <a href="/wiki/Pulse-code_modulation" title="Pulse-code modulation">PCM</a> sampled audio, and outputs packed digital bytes. When sent packed digital bytes, it outputs PCM sampled audio. The audio sample rate is fixed at 8 kHz. </p><p>The <a href="/wiki/Reference_implementation" title="Reference implementation">reference implementation</a> is open source and is freely available in a <a href="/wiki/GitHub" title="GitHub">GitHub</a> repository.<sup id="cite_ref-git_3-0" class="reference"><a href="#cite_note-git-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> The source code is released under the terms of version 2.1 of the <a href="/wiki/GNU_Lesser_General_Public_License" title="GNU Lesser General Public License">GNU Lesser General Public License</a> (LGPL).<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> It is programmed in <a href="/wiki/C_(programming_language)" title="C (programming language)">C</a> and current source code requires <a href="/wiki/Floating-point_arithmetic" title="Floating-point arithmetic">floating-point arithmetic</a>, although the algorithm itself does not require this. The reference software package also includes a <a href="/wiki/Frequency-division_multiplex" class="mw-redirect" title="Frequency-division multiplex">frequency-division multiplex</a> digital voice software modem and a graphical user interface based on <a href="/wiki/WxWidgets" title="WxWidgets">WxWidgets</a>. The software is developed on <a href="/wiki/Linux" title="Linux">Linux</a> and a port for <a href="/wiki/Microsoft_Windows" title="Microsoft Windows">Microsoft Windows</a> created with <a href="/wiki/Cygwin" title="Cygwin">Cygwin</a> is offered in addition to an Apple <a href="/wiki/MacOS" title="MacOS">MacOS</a> version. </p><p>The codec has been presented in various conferences and has received the 2012 <a href="/wiki/American_Radio_Relay_League" title="American Radio Relay League">ARRL</a> Technical Innovation Award,<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> and the Linux Australia Conference's Best Presentation Award.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Technology">Technology</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Codec_2&action=edit&section=2" title="Edit section: Technology"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Internally, parametric audio coding algorithms operate on 10 ms PCM frames using a model of the human voice. Each of these audio segments is declared <a href="/wiki/Voiced" class="mw-redirect" title="Voiced">voiced</a> (vowel) or unvoiced (consonant). </p><p>Codec 2 uses <a href="/wiki/Sinusoidal_model" title="Sinusoidal model">sinusoidal coding</a> to model speech, which is closely related to that of <a href="/wiki/Multi-band_excitation" class="mw-redirect" title="Multi-band excitation">multi-band excitation</a> codecs. Sinusoidal coding is based on regularities (periodicity) in the pattern of overtone frequencies and layers harmonic sinusoids. Spoken audio is recreated by modelling speech as a sum of harmonically related sine waves with independent amplitudes called <a href="/wiki/Line_spectral_pairs" title="Line spectral pairs">Line spectral pairs</a>, or LSP, on top of a determined <a href="/wiki/Fundamental_frequency" title="Fundamental frequency">fundamental frequency</a> of the speaker's voice (pitch). The (quantised) pitch and the amplitude (energy) of the <a href="/wiki/Harmonics" class="mw-redirect" title="Harmonics">harmonics</a> are encoded, and with the LSP's are exchanged across a channel in a digital format. The LSP coefficients represent the <a href="/wiki/Linear_predictive_coding" title="Linear predictive coding">Linear Predictive Coding</a> (LPC) model in the frequency domain, and lend themselves to a robust and efficient quantisation of the LPC parameters.<sup id="cite_ref-thesis_7-0" class="reference"><a href="#cite_note-thesis-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> </p><p>The digital bytes are in a bit-field format that have been packed together into bytes. These bit fields are also optionally <a href="/wiki/Gray_code" title="Gray code">gray coded</a> before being grouped together. The gray coding may be useful if sending raw, but normally an application will just burst the bit fields out. The bit fields make up the various parameters that are stored or exchanged (pitch, energy, voicing Booleans, LSP's, etc.). </p><p>For example, Mode 3200, has 20 ms of audio converted to 64 bits. So 64 bits will be output every 20 ms (50 times a second), for a minimum data rate of 3200 bit/s. These 64 bits are sent as 8 bytes to the application, which has to unwrap the bit fields, or send the bytes over a data channel. </p><p>Another example is Mode 1300, which is sent 40 ms of audio, and outputs 52 bits every 40 ms (25 times a second), for a minimum rate of 1300 bit/s. These 52 bits are sent as 7 bytes to the application or data channel. </p> <div class="mw-heading mw-heading2"><h2 id="Adoption">Adoption</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Codec_2&action=edit&section=3" title="Edit section: Adoption"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Codec 2 is currently used in several radios and Software Defined Radio Systems </p> <ul><li>FreeDV<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup></li> <li>FlexRadio 6000 series<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup></li> <li>SM1000<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup></li> <li>Quisk<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/M17_(amateur_radio)" title="M17 (amateur radio)">M17 Project</a><sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup></li></ul> <p>Codec2 has also been integrated into <a href="/wiki/FreeSWITCH" title="FreeSWITCH">FreeSWITCH</a> and there's a <a href="/wiki/Patch_(computing)" title="Patch (computing)">patch</a> available for support in <a href="/wiki/Asterisk_(PBX)" title="Asterisk (PBX)">Asterisk</a>. </p><p>There was an FM-to-Codec2 digital voice repeater in earth orbit on amateur radio <a href="/wiki/CubeSat" title="CubeSat">CubeSat</a> <i>LilacSat-1</i> (call sign ON02CN, <a href="/wiki/QB50" class="mw-redirect" title="QB50">QB50</a> constellation), which was launched and subsequently deployed from the <a href="/wiki/International_Space_Station" title="International Space Station">International Space Station</a> in 2017.<sup id="cite_ref-ARRL2017_13-0" class="reference"><a href="#cite_note-ARRL2017-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Codec_2&action=edit&section=4" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The prominent <a href="/wiki/Free_software" title="Free software">free software</a> advocate and <a href="/wiki/Amateur_radio_operator" title="Amateur radio operator">radio amateur</a> <a href="/wiki/Bruce_Perens" title="Bruce Perens">Bruce Perens</a> lobbied for the creation of a free speech codec for operation at less than 5 kbit/s. Since he did not have the background himself, he approached Jean-Marc Valin in 2008, who introduced him to lead developer David Grant Rowe, who has worked with Valin on <a href="/wiki/Speex" title="Speex">Speex</a> on several occasions. Rowe himself was also a radio amateur (amateur radio <a href="/wiki/Call_sign" title="Call sign">call sign</a> VK5DGR) and had experience in creating and using voice codecs and other signal processing algorithms for speech signals. He obtained a PhD in speech coding in the 1990s and was involved in the development of one of the first <a href="/wiki/Satellite_phone" title="Satellite phone">satellite telephony</a> systems (<a href="/w/index.php?title=Mobilesat&action=edit&redlink=1" class="new" title="Mobilesat (page does not exist)">Mobilesat</a>). </p><p>He agreed to the task and announced his decision to work on a format on August 21, 2009. He built on the research and findings from his doctoral thesis.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> The underlying sinusoidal modelling goes back to developments by Robert J. McAulay and Thomas F. Quatieri (MIT Lincoln labs) from the mid-1980s. </p><p>In August 2010, David Rowe published version 0.1 alpha.<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> Version 0.2 was released towards the end of 2011, introducing a mode with 1,400 bits/s and significant improvements in quantization. </p><p>In January 2012, at <a href="/wiki/Linux.conf.au" title="Linux.conf.au">linux.conf.au</a>, Jean-Marc Valin helped improve the quantization of line spectral pairs, which Rowe is less familiar with.<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> After several changes to the available bit rate modes in winter and spring 2011/2012, 2,400, 1,400 and 1,200 bit/s modes were available after May of that year. </p><p>Codec 2 700C, a new mode with a bit rate of 700 bit/s, was finished in early 2017.<sup id="cite_ref-Slashdot170113_18-0" class="reference"><a href="#cite_note-Slashdot170113-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> </p><p>In July 2018 an experimental 450 bit/s mode was demonstrated, which was developed as part of a master thesis at the University of Erlangen-Nuremberg. By clever training of the vector quantization the data rate could be further reduced based on the principle of the 700C mode.<sup id="cite_ref-Southgate2018_19-0" class="reference"><a href="#cite_note-Southgate2018-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Codec_2&action=edit&section=5" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-columns references-column-width reflist-columns-2"> <ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.tapr.org/pdf/DCC2011-Codec2-VK5DGR.pdf">"DCC2011-Codec2-VK5DGR"</a> <span class="cs1-format">(PDF)</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=DCC2011-Codec2-VK5DGR&rft_id=http%3A%2F%2Fwww.tapr.org%2Fpdf%2FDCC2011-Codec2-VK5DGR.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACodec+2" class="Z3988"></span></span> </li> <li id="cite_note-jmspeex-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-jmspeex_2-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20150619052003/http://jmspeex.livejournal.com/10446.html">"A Pitch-Energy Quantizer for Codec2"</a>. 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href="/wiki/H.262/MPEG-2_Part_2" title="H.262/MPEG-2 Part 2">H.262</a></li> <li><a href="/wiki/H.263" title="H.263">H.263</a></li> <li><a href="/wiki/Advanced_Video_Coding" title="Advanced Video Coding">H.264 / AVC</a></li> <li><a href="/wiki/High_Efficiency_Video_Coding" title="High Efficiency Video Coding">H.265 / HEVC</a></li> <li><a href="/wiki/Versatile_Video_Coding" title="Versatile Video Coding">H.266 / VVC</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Society_of_Motion_Picture_and_Television_Engineers" title="Society of Motion Picture and Television Engineers">SMPTE</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/VC-1" title="VC-1">VC-1</a></li> <li><a href="/wiki/Dirac_(video_compression_format)" title="Dirac (video compression format)">VC-2</a></li> <li><a href="/wiki/Avid_DNxHD" title="Avid DNxHD">VC-3</a></li> <li><a href="/wiki/CineForm" title="CineForm">VC-5</a></li> <li><a href="/wiki/VC-6" title="VC-6">VC-6</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/On2_Technologies" title="On2 Technologies">TrueMotion</a> and AOMedia</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/On2_Technologies#TrueMotion_S" title="On2 Technologies">TrueMotion S</a></li> <li><a href="/wiki/VP3" title="VP3">VP3</a></li> <li><a href="/wiki/VP6" title="VP6">VP6</a></li> <li><a href="/wiki/VP7" class="mw-redirect" title="VP7">VP7</a></li> <li><a href="/wiki/VP8" title="VP8">VP8</a></li> <li><a href="/wiki/VP9" title="VP9">VP9</a></li> <li><a href="/wiki/AV1" title="AV1">AV1</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em">Chinese Standard</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Audio_Video_Standard#First_generation" title="Audio Video Standard">AVS1 P2/AVS+</a>(GB/T 20090.2/16)</li> <li><a href="/wiki/Audio_Video_Standard#Second_generation" title="Audio Video Standard">AVS2 P2</a>(GB/T 33475.2,GY/T 299.1) <ul><li>HDR Vivid(GY/T 358)</li></ul></li> <li>AVS3 P2(GY/T 368)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em">Others</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Apple_Video" title="Apple Video">Apple Video</a></li> <li><a href="/wiki/Audio_Video_Standard" title="Audio Video Standard">AVS</a></li> <li><a href="/wiki/Bink_Video" title="Bink Video">Bink</a></li> <li><a href="/wiki/Cinepak" title="Cinepak">Cinepak</a></li> <li><a href="/wiki/Daala" title="Daala">Daala</a></li> <li><a href="/wiki/Digital_Video_Interactive" title="Digital Video Interactive">DVI</a></li> <li><a href="/wiki/FFV1" title="FFV1">FFV1</a></li> <li><a href="/wiki/Huffyuv" title="Huffyuv">Huffyuv</a></li> <li><a href="/wiki/Indeo" title="Indeo">Indeo</a></li> <li><a href="/wiki/Lagarith" title="Lagarith">Lagarith</a></li> <li><a href="/wiki/Microsoft_Video_1" title="Microsoft Video 1">Microsoft Video 1</a></li> <li><a href="/wiki/MSU_Lossless_Video_Codec" title="MSU Lossless Video Codec">MSU Lossless</a></li> <li><a href="/wiki/OMS_Video" title="OMS Video">OMS Video</a></li> <li><a href="/wiki/Pixlet" title="Pixlet">Pixlet</a></li> <li><a href="/wiki/Apple_ProRes" title="Apple ProRes">ProRes</a> <ul><li><a href="/wiki/ProRes_422" class="mw-redirect" title="ProRes 422">422</a></li> <li><a href="/wiki/ProRes_4444" class="mw-redirect" title="ProRes 4444">4444</a></li></ul></li> <li>QuickTime <ul><li><a href="/wiki/QuickTime_Animation" title="QuickTime Animation">Animation</a></li> <li><a href="/wiki/QuickTime_Graphics" title="QuickTime Graphics">Graphics</a></li></ul></li> <li><a href="/wiki/RealVideo" title="RealVideo">RealVideo</a></li> <li><a href="/wiki/RTVideo" title="RTVideo">RTVideo</a></li> <li><a href="/wiki/SheerVideo" title="SheerVideo">SheerVideo</a></li> <li><a href="/wiki/Smacker_video" title="Smacker video">Smacker</a></li> <li><a href="/wiki/Sorenson_Media" title="Sorenson Media">Sorenson Video/Spark</a></li> <li><a href="/wiki/Theora" title="Theora">Theora</a></li> <li><a href="/wiki/Thor_(video_codec)" title="Thor (video codec)">Thor</a></li> <li><a href="/wiki/Ut_Video_Codec_Suite" title="Ut Video Codec Suite">Ut</a></li> <li><a href="/wiki/Windows_Media_Video" title="Windows Media Video">WMV</a></li> <li><a href="/wiki/RatDVD" title="RatDVD">XEB</a></li> <li><a href="/wiki/YULS" title="YULS">YULS</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Audio_coding_format" title="Audio coding format">Audio<br />compression</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/International_Organization_for_Standardization" title="International Organization for Standardization">ISO</a>, <a href="/wiki/International_Electrotechnical_Commission" title="International Electrotechnical Commission">IEC</a>,<br /> <a href="/wiki/Moving_Picture_Experts_Group" title="Moving Picture Experts Group">MPEG</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/MPEG-1_Audio_Layer_II" title="MPEG-1 Audio Layer II">MPEG-1 Layer II</a> <ul><li><a href="/wiki/MPEG_Multichannel" title="MPEG Multichannel">Multichannel</a></li></ul></li> <li><a href="/wiki/MPEG-1_Audio_Layer_I" title="MPEG-1 Audio Layer I">MPEG-1 Layer I</a></li> <li><a href="/wiki/MP3" title="MP3">MPEG-1 Layer III (MP3)</a></li> <li><a href="/wiki/Advanced_Audio_Coding" title="Advanced Audio Coding">AAC</a> <ul><li><a href="/wiki/High-Efficiency_Advanced_Audio_Coding" title="High-Efficiency Advanced Audio Coding">HE-AAC</a></li> <li><a href="/wiki/AAC-LD" title="AAC-LD">AAC-LD</a></li></ul></li> <li><a href="/wiki/MPEG_Surround" title="MPEG Surround">MPEG Surround</a></li> <li><a href="/wiki/Audio_Lossless_Coding" title="Audio Lossless Coding">MPEG-4 ALS</a></li> <li><a href="/wiki/MPEG-4_SLS" title="MPEG-4 SLS">MPEG-4 SLS</a></li> <li><a href="/wiki/Super_Audio_CD#DST" title="Super Audio CD">MPEG-4 DST</a></li> <li><a href="/wiki/Harmonic_Vector_Excitation_Coding" title="Harmonic Vector Excitation Coding">MPEG-4 HVXC</a></li> <li><a href="/wiki/Code-excited_linear_prediction" title="Code-excited linear prediction">MPEG-4 CELP</a></li> <li><a href="/wiki/Unified_Speech_and_Audio_Coding" title="Unified Speech and Audio Coding">MPEG-D USAC</a></li> <li><a href="/wiki/MPEG-H_3D_Audio" title="MPEG-H 3D Audio">MPEG-H 3D Audio</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/ITU-T" title="ITU-T">ITU-T</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/G.711" title="G.711">G.711</a> <ul><li><a href="/wiki/A-law_algorithm" title="A-law algorithm">A-law</a></li> <li><a href="/wiki/%CE%9C-law_algorithm" title="Μ-law algorithm">µ-law</a></li></ul></li> <li><a href="/wiki/G.718" title="G.718">G.718</a></li> <li><a href="/wiki/G.719" title="G.719">G.719</a></li> <li><a href="/wiki/G.722" title="G.722">G.722</a></li> <li><a href="/wiki/G.722.1" title="G.722.1">G.722.1</a></li> <li><a href="/wiki/Adaptive_Multi-Rate_Wideband" title="Adaptive Multi-Rate Wideband">G.722.2</a></li> <li><a href="/wiki/G.723" title="G.723">G.723</a></li> <li><a href="/wiki/G.723.1" title="G.723.1">G.723.1</a></li> <li><a href="/wiki/G.726" title="G.726">G.726</a></li> <li><a href="/wiki/G.728" title="G.728">G.728</a></li> <li><a href="/wiki/G.729" title="G.729">G.729</a></li> <li><a href="/wiki/G.729.1" title="G.729.1">G.729.1</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Internet_Engineering_Task_Force" title="Internet Engineering Task Force">IETF</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Opus_(audio_format)" title="Opus (audio format)">Opus</a></li> <li><a href="/wiki/Internet_Low_Bitrate_Codec" title="Internet Low Bitrate Codec">iLBC</a></li> <li><a href="/wiki/Speex" title="Speex">Speex</a></li> <li><a href="/wiki/Vorbis" title="Vorbis">Vorbis</a></li> <li><a href="/wiki/FLAC" title="FLAC">FLAC</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/3GPP" title="3GPP">3GPP</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Adaptive_Multi-Rate_audio_codec" title="Adaptive Multi-Rate audio codec">AMR</a></li> <li><a href="/wiki/Adaptive_Multi-Rate_Wideband" title="Adaptive Multi-Rate Wideband">AMR-WB</a></li> <li><a href="/wiki/Extended_Adaptive_Multi-Rate_%E2%80%93_Wideband" title="Extended Adaptive Multi-Rate – Wideband">AMR-WB+</a></li> <li><a href="/wiki/Enhanced_Variable_Rate_Codec" title="Enhanced Variable Rate Codec">EVRC</a></li> <li><a href="/wiki/Enhanced_Variable_Rate_Codec_B" title="Enhanced Variable Rate Codec B">EVRC-B</a></li> <li><a href="/wiki/Enhanced_Voice_Services" title="Enhanced Voice Services">EVS</a></li> <li><a href="/wiki/Half_Rate" title="Half Rate">GSM-HR</a></li> <li><a href="/wiki/Full_Rate" title="Full Rate">GSM-FR</a></li> <li><a href="/wiki/Enhanced_full_rate" title="Enhanced full rate">GSM-EFR</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/ETSI" class="mw-redirect" title="ETSI">ETSI</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Dolby_Digital" title="Dolby Digital">AC-3</a></li> <li><a href="/wiki/Dolby_AC-4" title="Dolby AC-4">AC-4</a></li> <li><a href="/wiki/DTS_(sound_system)" class="mw-redirect" title="DTS (sound system)">DTS</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Bluetooth_Special_Interest_Group" title="Bluetooth Special Interest Group">Bluetooth SIG</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/SBC_(codec)" title="SBC (codec)">SBC</a></li> <li><a href="/wiki/LC3_(codec)" title="LC3 (codec)">LC3</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em">Chinese Standard</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Audio_Video_Standard#First_generation" title="Audio Video Standard">AVS1 P10</a>(GB/T 20090.10)</li> <li><a href="/wiki/Audio_Video_Standard#Second_generation" title="Audio Video Standard">AVS2 P3</a>(GB/T 33475.3) <ul><li><a href="/w/index.php?title=Audio_Vivid&action=edit&redlink=1" class="new" title="Audio Vivid (page does not exist)">Audio Vivid</a>(GY/T 363)</li></ul></li> <li><a href="/wiki/Dynamic_Resolution_Adaptation" title="Dynamic Resolution Adaptation">DRA</a>(GB/T 22726)</li> <li><a href="/wiki/L2HC" title="L2HC">L2HC</a></li> <li>ExAC(SJ/T 11299.4)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em">Others</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Algebraic_code-excited_linear_prediction" title="Algebraic code-excited linear prediction">ACELP</a></li> <li><a href="/wiki/Apple_Lossless_Audio_Codec" title="Apple Lossless Audio Codec">ALAC</a></li> <li><a href="/wiki/Asao_(codec)" title="Asao (codec)">Asao</a></li> <li><a href="/wiki/Adaptive_Transform_Acoustic_Coding" class="mw-redirect" title="Adaptive Transform Acoustic Coding">ATRAC</a></li> <li><a href="/wiki/CELT" title="CELT">CELT</a></li> <li><a class="mw-selflink selflink">Codec 2</a></li> <li><a href="/wiki/Internet_Speech_Audio_Codec" title="Internet Speech Audio Codec">iSAC</a></li> <li><a href="/wiki/Lyra_(codec)" title="Lyra (codec)">Lyra</a></li> <li><a href="/wiki/Mixed-excitation_linear_prediction" title="Mixed-excitation linear prediction">MELP</a></li> <li><a href="/wiki/Monkey%27s_Audio" title="Monkey's Audio">Monkey's Audio</a></li> <li><a href="/wiki/MT9" title="MT9">MT9</a></li> <li><a href="/wiki/Musepack" title="Musepack">Musepack</a></li> <li><a href="/wiki/OptimFROG" title="OptimFROG">OptimFROG</a></li> <li><a href="/wiki/Original_Sound_Quality" title="Original Sound Quality">OSQ</a></li> <li><a href="/wiki/Qualcomm_code-excited_linear_prediction" title="Qualcomm code-excited linear prediction">QCELP</a></li> <li><a href="/wiki/Relaxed_code-excited_linear_prediction" title="Relaxed code-excited linear prediction">RCELP</a></li> <li><a href="/wiki/RealAudio" title="RealAudio">RealAudio</a></li> <li><a href="/wiki/RTAudio" title="RTAudio">RTAudio</a></li> <li><a href="/wiki/Avid_Audio#Sound_Designer_file_formats" title="Avid Audio">SD2</a></li> <li><a href="/wiki/Shorten_file_format" class="mw-redirect" title="Shorten file format">SHN</a></li> <li><a href="/wiki/SILK" title="SILK">SILK</a></li> <li><a href="/wiki/Siren_(codec)" title="Siren (codec)">Siren</a></li> <li><a href="/wiki/Selectable_Mode_Vocoder" title="Selectable Mode Vocoder">SMV</a></li> <li><a href="/wiki/SVOPC" title="SVOPC">SVOPC</a></li> <li>TTA <ul><li>True Audio</li></ul></li> <li><a href="/wiki/TwinVQ" title="TwinVQ">TwinVQ</a></li> <li><a href="/wiki/Variable-Rate_Multimode_Wideband" title="Variable-Rate Multimode Wideband">VMR-WB</a></li> <li><a href="/wiki/Vector_sum_excited_linear_prediction" title="Vector sum excited linear prediction">VSELP</a></li> <li><a href="/wiki/WavPack" title="WavPack">WavPack</a></li> <li><a href="/wiki/Windows_Media_Audio" title="Windows Media Audio">WMA</a></li> <li><a href="/wiki/Master_Quality_Authenticated" title="Master Quality Authenticated">MQA</a></li> <li><a href="/wiki/AptX" title="AptX">aptX</a></li> <li><a href="/wiki/AptX#aptX_HD" title="AptX">aptX HD</a></li> <li><a href="/wiki/AptX#aptX_Low_Latency" title="AptX">aptX Low Latency</a></li> <li><a href="/wiki/AptX#aptX_Adaptive" title="AptX">aptX Adaptive</a></li> <li><a href="/wiki/LDAC_(codec)" title="LDAC (codec)">LDAC</a></li> <li><a href="/wiki/LHDC_(codec)" title="LHDC (codec)">LHDC</a></li> <li><a href="/wiki/LHDC_(codec)#LLAC" title="LHDC (codec)">LLAC</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Image_compression" title="Image compression">Image<br />compression</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/International_Electrotechnical_Commission" title="International Electrotechnical Commission">IEC</a>, <a href="/wiki/International_Organization_for_Standardization" title="International Organization for Standardization">ISO</a>, <a href="/wiki/Internet_Engineering_Task_Force" title="Internet Engineering Task Force">IETF</a>, <br /><a href="/wiki/World_Wide_Web_Consortium" title="World Wide Web Consortium">W3C</a>, <a href="/wiki/ITU-T" title="ITU-T">ITU-T</a>, <a href="/wiki/Joint_Photographic_Experts_Group" title="Joint Photographic Experts Group">JPEG</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Group_4_compression" title="Group 4 compression">CCITT Group 4</a></li> <li><a href="/wiki/GIF" title="GIF">GIF</a></li> <li><a href="/wiki/High_Efficiency_Image_File_Format#HEIC:_HEVC_in_HEIF" title="High Efficiency Image File Format">HEIC / HEIF</a></li> <li><a href="/wiki/High_Efficiency_Video_Coding#Main_Still_Picture" title="High Efficiency Video Coding">HEVC</a></li> <li><a href="/wiki/JBIG" title="JBIG">JBIG</a></li> <li><a href="/wiki/JBIG2" title="JBIG2">JBIG2</a></li> <li><a href="/wiki/JPEG" title="JPEG">JPEG</a></li> <li><a href="/wiki/JPEG_2000" title="JPEG 2000">JPEG 2000</a></li> <li><a href="/wiki/JPEG-LS" class="mw-redirect" title="JPEG-LS">JPEG-LS</a></li> <li><a href="/wiki/JPEG_XL" title="JPEG XL">JPEG XL</a></li> <li><a href="/wiki/JPEG_XR" title="JPEG XR">JPEG XR</a></li> <li><a href="/wiki/JPEG_XS" title="JPEG XS">JPEG XS</a></li> <li><a href="/wiki/JPEG_XT" title="JPEG XT">JPEG XT</a></li> <li><a href="/wiki/Portable_Network_Graphics" class="mw-redirect" title="Portable Network Graphics">PNG</a></li> <li><a href="/wiki/TIFF" title="TIFF">TIFF</a></li> <li><a href="/wiki/TIFF/EP" title="TIFF/EP">TIFF/EP</a></li> <li><a href="/wiki/TIFF/IT" class="mw-redirect" title="TIFF/IT">TIFF/IT</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em">Others</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/APNG" title="APNG">APNG</a></li> <li><a href="/wiki/AV1" title="AV1">AV1</a></li> <li><a href="/wiki/AVIF" title="AVIF">AVIF</a></li> <li><a href="/wiki/Better_Portable_Graphics" title="Better Portable Graphics">BPG</a></li> <li><a href="/wiki/DjVu" title="DjVu">DjVu</a></li> <li><a href="/wiki/OpenEXR" title="OpenEXR">EXR</a></li> <li><a href="/wiki/Free_Lossless_Image_Format" title="Free Lossless Image Format">FLIF</a></li> <li><a href="/wiki/ICER_(file_format)" title="ICER (file format)">ICER</a></li> <li><a href="/wiki/Multiple-image_Network_Graphics" title="Multiple-image Network Graphics">MNG</a></li> <li><a href="/wiki/Progressive_Graphics_File" title="Progressive Graphics File">PGF</a></li> <li><a href="/wiki/QOI_(image_format)" title="QOI (image format)">QOI</a></li> <li><a href="/wiki/QuickTime_VR" title="QuickTime VR">QTVR</a></li> <li><a href="/wiki/Wireless_Application_Protocol_Bitmap_Format" title="Wireless Application Protocol Bitmap Format">WBMP</a></li> <li><a href="/wiki/WebP" title="WebP">WebP</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Digital_container_format" class="mw-redirect" title="Digital container format">Containers</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/International_Organization_for_Standardization" title="International Organization for Standardization">ISO</a>, <a href="/wiki/International_Electrotechnical_Commission" title="International Electrotechnical Commission">IEC</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/MPEG_elementary_stream" title="MPEG elementary stream">MPEG-ES</a> <ul><li><a href="/wiki/Packetized_elementary_stream" title="Packetized elementary stream">MPEG-PES</a></li></ul></li> <li><a href="/wiki/MPEG_program_stream" title="MPEG program stream">MPEG-PS</a></li> <li><a href="/wiki/MPEG_transport_stream" title="MPEG transport stream">MPEG-TS</a></li> <li><a href="/wiki/ISO/IEC_base_media_file_format" class="mw-redirect" title="ISO/IEC base media file format">ISO/IEC base media file format</a></li> <li><a href="/wiki/MPEG-4_Part_14" class="mw-redirect" title="MPEG-4 Part 14">MPEG-4 Part 14</a> (MP4)</li> <li><a href="/wiki/Motion_JPEG_2000" title="Motion JPEG 2000">Motion JPEG 2000</a></li> <li><a href="/wiki/MPEG-21" title="MPEG-21">MPEG-21 Part 9</a></li> <li><a href="/wiki/MPEG_media_transport" title="MPEG media transport">MPEG media transport</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/ITU-T" title="ITU-T">ITU-T</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/MPEG-2#Systems" title="MPEG-2">H.222.0</a></li> <li><a href="/wiki/Motion_JPEG_2000" title="Motion JPEG 2000">T.802</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Internet_Engineering_Task_Force" title="Internet Engineering Task Force">IETF</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Real-time_Transport_Protocol" title="Real-time Transport Protocol">RTP</a></li> <li><a href="/wiki/Ogg" title="Ogg">Ogg</a></li> <li><a href="/wiki/Matroska" title="Matroska">Matroska</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Society_of_Motion_Picture_and_Television_Engineers" title="Society of Motion Picture and Television Engineers">SMPTE</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/General_Exchange_Format" title="General Exchange Format">GXF</a></li> <li><a href="/wiki/Material_Exchange_Format" title="Material Exchange Format">MXF</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em">Others</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/3GP_and_3G2" title="3GP and 3G2">3GP and 3G2</a></li> <li><a href="/wiki/AMV_video_format" title="AMV video format">AMV</a></li> <li><a href="/wiki/Advanced_Systems_Format" title="Advanced Systems Format">ASF</a></li> <li><a href="/wiki/Audio_Interchange_File_Format" title="Audio Interchange File Format">AIFF</a></li> <li><a href="/wiki/Audio_Video_Interleave" title="Audio Video Interleave">AVI</a></li> <li><a href="/wiki/Au_file_format" title="Au file format">AU</a></li> <li><a href="/wiki/Better_Portable_Graphics" title="Better Portable Graphics">BPG</a></li> <li><a href="/wiki/Bink_Video" title="Bink Video">Bink</a> <ul><li><a href="/wiki/Smacker_video" title="Smacker video">Smacker</a></li></ul></li> <li><a href="/wiki/BMP_file_format" title="BMP file format">BMP</a></li> <li><a href="/wiki/DivX#DivX_Media_Format_(DMF)" title="DivX">DivX Media Format</a></li> <li><a href="/wiki/Enhanced_VOB" title="Enhanced VOB">EVO</a></li> <li><a href="/wiki/Flash_Video" title="Flash Video">Flash Video</a></li> <li><a href="/wiki/High_Efficiency_Image_File_Format" title="High Efficiency Image File Format">HEIF</a></li> <li><a href="/wiki/Interchange_File_Format" title="Interchange File Format">IFF</a></li> <li><a href="/wiki/.m2ts" title=".m2ts">M2TS</a></li> <li><a href="/wiki/Matroska" title="Matroska">Matroska</a> <ul><li><a href="/wiki/WebM" title="WebM">WebM</a></li></ul></li> <li><a href="/wiki/QuickTime_File_Format" title="QuickTime File Format">QuickTime File Format</a></li> <li><a href="/wiki/RatDVD" title="RatDVD">RatDVD</a></li> <li><a href="/wiki/RealMedia" title="RealMedia">RealMedia</a></li> <li><a href="/wiki/Resource_Interchange_File_Format" title="Resource Interchange File Format">RIFF</a> <ul><li><a href="/wiki/WAV" title="WAV">WAV</a></li></ul></li> <li><a href="/wiki/MOD_and_TOD" title="MOD and TOD">MOD and TOD</a></li> <li><a href="/wiki/VOB" title="VOB">VOB, IFO and BUP</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Collaborations</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/NETVC" title="NETVC">NETVC</a></li> <li><a href="/wiki/MPEG_LA" title="MPEG LA">MPEG LA</a></li> <li><a href="/wiki/Alliance_for_Open_Media" title="Alliance for Open Media">Alliance for Open Media</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Data_compression" title="Data compression">Methods</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Entropy_encoding" class="mw-redirect" title="Entropy encoding">Entropy</a> <ul><li><a href="/wiki/Arithmetic_coding" title="Arithmetic coding">Arithmetic</a></li> <li><a href="/wiki/Huffman_coding" title="Huffman coding">Huffman</a></li> <li><a href="/wiki/Modified_Huffman_coding" title="Modified Huffman coding">Modified</a></li></ul></li> <li><a href="/wiki/Linear_predictive_coding" title="Linear predictive coding">LPC</a> <ul><li><a href="/wiki/Algebraic_code-excited_linear_prediction" title="Algebraic code-excited linear prediction">ACELP</a></li> <li><a href="/wiki/Code-excited_linear_prediction" title="Code-excited linear prediction">CELP</a></li> <li><a href="/wiki/Line_spectral_pairs" title="Line spectral pairs">LSP</a></li> <li><a href="/wiki/Warped_linear_predictive_coding" title="Warped linear predictive coding">WLPC</a></li></ul></li> <li><a href="/wiki/Lossless_compression" title="Lossless compression">Lossless</a></li> <li><a href="/wiki/Lossy_compression" title="Lossy compression">Lossy</a></li> <li><a href="/wiki/LZ77_and_LZ78" title="LZ77 and LZ78">LZ</a> <ul><li><a href="/wiki/DEFLATE" class="mw-redirect" title="DEFLATE">DEFLATE</a></li> <li><a href="/wiki/Lempel%E2%80%93Ziv%E2%80%93Welch" title="Lempel–Ziv–Welch">LZW</a></li></ul></li> <li><a href="/wiki/Pulse-code_modulation" title="Pulse-code modulation">PCM</a> <ul><li><a href="/wiki/A-law_algorithm" title="A-law algorithm">A-law</a></li> <li><a href="/wiki/%CE%9C-law_algorithm" title="Μ-law algorithm">µ-law</a></li> <li><a href="/wiki/Adaptive_differential_pulse-code_modulation" title="Adaptive differential pulse-code modulation">ADPCM</a></li> <li><a href="/wiki/Differential_pulse-code_modulation" title="Differential pulse-code modulation">DPCM</a></li></ul></li> <li><a href="/wiki/Transform_coding" title="Transform coding">Transforms</a> <ul><li><a href="/wiki/Discrete_cosine_transform" title="Discrete cosine transform">DCT</a></li> <li><a href="/wiki/Fast_Fourier_transform" title="Fast Fourier transform">FFT</a></li> <li><a href="/wiki/Modified_discrete_cosine_transform" title="Modified discrete cosine transform">MDCT</a></li> <li><a href="/wiki/Wavelet" title="Wavelet">Wavelet</a> <ul><li><a href="/wiki/Daubechies_wavelet" title="Daubechies wavelet">Daubechies</a></li> <li><a href="/wiki/Discrete_wavelet_transform" title="Discrete wavelet transform">DWT</a></li></ul></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Lists</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Comparison_of_audio_coding_formats" title="Comparison of audio coding formats">Comparison of audio coding formats</a></li> <li><a href="/wiki/Comparison_of_video_codecs" title="Comparison of video codecs">Comparison of video codecs</a></li> <li><a href="/wiki/List_of_codecs" title="List of codecs">List of codecs</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div>See <a href="/wiki/Template:Compression_methods" title="Template:Compression methods">Compression methods</a> for techniques and <a href="/wiki/Template:Compression_software" title="Template:Compression software">Compression software</a> for codecs</div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Data_compression_software" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Compression_software" title="Template:Compression software"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Compression_software" title="Template talk:Compression software"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Compression_software" title="Special:EditPage/Template:Compression software"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Data_compression_software" style="font-size:114%;margin:0 4em"><a href="/wiki/Data_compression" title="Data compression">Data compression</a> software</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Comparison_of_file_archivers" title="Comparison of file archivers">Archivers</a> with<br /> compression<br /> <span style="font-size:85%;">(<a href="/wiki/Comparison_of_file_archivers" title="Comparison of file archivers">comparison</a>)</span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:7em"><a href="/wiki/Free_software" title="Free software">Free software</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/7-Zip" title="7-Zip">7-Zip</a></li> <li><a href="/wiki/Ark_(software)" title="Ark (software)">Ark</a></li> <li><a href="/wiki/Haiku_Applications#Expander" class="mw-redirect" title="Haiku Applications">Expander</a></li> <li><a href="/wiki/FreeArc" title="FreeArc">FreeArc</a></li> <li><a href="/wiki/GNOME_Archive_Manager" class="mw-redirect" title="GNOME Archive Manager">GNOME Archive Manager</a></li> <li><a href="/wiki/Info-ZIP" title="Info-ZIP">Info-ZIP</a></li> <li><a href="/wiki/KGB_Archiver" title="KGB Archiver">KGB Archiver</a></li> <li><a href="/wiki/PAQ" title="PAQ">PAQ</a></li> <li><a href="/wiki/Pax_(command)" title="Pax (command)">pax</a></li> <li><a href="/wiki/PeaZip" title="PeaZip">PeaZip</a></li> <li><a href="/wiki/XAD_(software)" title="XAD (software)">XAD</a> (decompression only)</li> <li><a href="/wiki/Xarchiver" title="Xarchiver">Xarchiver</a></li> <li><a href="/wiki/Zipeg" title="Zipeg">Zipeg</a></li> <li><a href="/wiki/ZPAQ" title="ZPAQ">ZPAQ</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em"><a href="/wiki/Freeware" title="Freeware">Freeware</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Filzip" title="Filzip">Filzip</a></li> <li><a href="/wiki/LHA_(file_format)" title="LHA (file format)">LHA</a></li> <li><a href="/wiki/Lhasa_(computing)" title="Lhasa (computing)">Lhasa</a> (decompression only)</li> <li><a href="/wiki/StuffIt_Expander" title="StuffIt Expander">StuffIt Expander</a> (decompression only)</li> <li><a href="/wiki/The_Unarchiver" title="The Unarchiver">The Unarchiver</a> (decompression only)</li> <li><a href="/wiki/TUGZip" title="TUGZip">TUGZip</a></li> <li><a href="/wiki/ZipGenius" title="ZipGenius">ZipGenius</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em"><a href="/wiki/Commercial_software" title="Commercial software">Commercial</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ARC_(file_format)" title="ARC (file format)">ARC</a></li> <li><a href="/wiki/ALZip" title="ALZip">ALZip</a></li> <li><a href="/wiki/Archive_Utility" class="mw-redirect" title="Archive Utility">Archive Utility</a></li> <li><a href="/wiki/ARJ" title="ARJ">ARJ</a></li> <li><a href="/wiki/BetterZip" title="BetterZip">BetterZip</a></li> <li><a href="/wiki/MacBinary" title="MacBinary">MacBinary</a></li> <li><a href="/wiki/PKZIP" title="PKZIP">PKZIP/SecureZIP</a></li> <li><a href="/wiki/PowerArchiver" title="PowerArchiver">PowerArchiver</a></li> <li><a href="/wiki/StuffIt" title="StuffIt">StuffIt</a></li> <li><a href="/wiki/WinAce" title="WinAce">WinAce</a></li> <li><a href="/wiki/WinRAR" title="WinRAR">WinRAR</a></li> <li><a href="/wiki/WinZip" title="WinZip">WinZip</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Non-archiving<br />compressors</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:7em">Generic</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bzip2" title="Bzip2">bzip2</a></li> <li><a href="/wiki/Compress_(software)" title="Compress (software)">compress</a></li> <li><a href="/wiki/Gzip" title="Gzip">gzip</a></li> <li><a href="/wiki/Lzip" title="Lzip">lzip</a></li> <li><a href="/wiki/Lzop" title="Lzop">lzop</a></li> <li><a href="/wiki/Pack_(software)" title="Pack (software)">pack</a></li> <li><a href="/wiki/Rzip" title="Rzip">rzip</a></li> <li><a href="/wiki/Snappy_(compression)" title="Snappy (compression)">Snappy</a></li> <li><a href="/wiki/XZ_Utils" title="XZ Utils">XZ Utils</a></li> <li><a href="/wiki/Zstd" title="Zstd">zstd</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em"><a href="/wiki/Executable_compression" title="Executable compression">For code</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"><a href="/wiki/UPX" title="UPX">UPX</a></div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Data_compression#Audio" title="Data compression">Audio<br /> compression</a><br /> <span style="font-size:85%;">(<a href="/wiki/Comparison_of_audio_coding_formats" title="Comparison of audio coding formats">comparison</a>)</span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:7em;padding-top:5px; padding-bottom:5px"><a href="/wiki/Lossy_compression" title="Lossy compression">Lossy</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Advanced_Audio_Coding" title="Advanced Audio Coding">AAC</a> <ul><li><a href="/wiki/Fraunhofer_FDK_AAC" title="Fraunhofer FDK AAC">Fraunhofer FDK AAC</a></li> <li><a href="/wiki/Nero_AAC_Codec" title="Nero AAC Codec">Nero AAC Codec</a></li> <li><a href="/wiki/FAAC" title="FAAC">FAAC</a></li></ul></li> <li><a href="/wiki/Helix_(multimedia_project)" title="Helix (multimedia project)">Helix DNA Producer</a></li> <li><a href="/wiki/MP3" title="MP3">MP3</a> <ul><li><a href="/wiki/L3enc" title="L3enc">l3enc</a></li> <li><a href="/wiki/LAME" title="LAME">LAME</a></li></ul></li> <li><a href="/wiki/TooLAME" title="TooLAME">TooLAME</a></li> <li><a href="/wiki/Libavcodec" title="Libavcodec">libavcodec</a></li> <li><a href="/wiki/CELT" title="CELT">libcelt</a></li> <li><a href="/wiki/Opus_(audio_format)" title="Opus (audio format)">libopus</a></li> <li><a href="/wiki/Speex" title="Speex">libspeex</a></li> <li><a href="/wiki/Musepack" title="Musepack">Musepack</a></li> <li><a href="/wiki/Vorbis" title="Vorbis">libvorbis</a></li> <li><a href="/wiki/Windows_Media_Encoder" title="Windows Media Encoder">Windows Media Encoder</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em;padding-top:5px; padding-bottom:5px"><a href="/wiki/Lossless_compression" title="Lossless compression">Lossless</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Apple_Lossless_Audio_Codec" title="Apple Lossless Audio Codec">ALAC</a></li> <li><a href="/wiki/FLAC" title="FLAC">FLAC</a></li> <li><a href="/wiki/Libavcodec" title="Libavcodec">libavcodec</a></li> <li><a href="/wiki/Monkey%27s_Audio" title="Monkey's Audio">Monkey's Audio</a></li> <li><a href="/wiki/Audio_Lossless_Coding" title="Audio Lossless Coding">mp4als</a></li> <li><a href="/wiki/OptimFROG" title="OptimFROG">OptimFROG</a></li> <li><a href="/wiki/Shorten_(codec)" title="Shorten (codec)">Shorten</a></li> <li><a href="/wiki/WavPack" title="WavPack">WavPack</a></li> <li><a href="/wiki/L2HC" title="L2HC">L2HC</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Data_compression#Video" title="Data compression">Video<br /> compression</a><br /> <span style="font-size:85%;">(<a href="/wiki/Comparison_of_video_codecs" title="Comparison of video codecs">comparison</a>)</span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:7em"><a href="/wiki/Lossy_compression" title="Lossy compression">Lossy</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/MPEG-4_Part_2" title="MPEG-4 Part 2">MPEG-4 ASP</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/3ivx" title="3ivx">3ivx</a></li> <li><a href="/wiki/DivX" title="DivX">DivX</a></li> <li><a href="/wiki/Nero_Digital" title="Nero Digital">Nero Digital</a></li> <li><a href="/wiki/FFmpeg" title="FFmpeg">FFmpeg</a></li> <li><a href="/wiki/HDX4" title="HDX4">HDX4</a></li> <li><a href="/wiki/Xvid" title="Xvid">Xvid</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Advanced_Video_Coding" title="Advanced Video Coding">H.264</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/CoreAVC" title="CoreAVC">CoreAVC</a></li> <li>Blu-code</li> <li><a href="/wiki/DivX" title="DivX">DivX</a></li> <li><a href="/wiki/FFmpeg" title="FFmpeg">FFmpeg</a></li> <li><a href="/wiki/Nero_Digital" title="Nero Digital">Nero Digital</a></li> <li><a href="/wiki/OpenH264" title="OpenH264">OpenH264</a></li> <li><a href="/wiki/QuickTime" title="QuickTime">QuickTime</a></li> <li><a href="/wiki/X264" title="X264">x264</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/High_Efficiency_Video_Coding" title="High Efficiency Video Coding">HEVC</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/DivX" title="DivX">DivX</a></li> <li><a href="/wiki/X265" title="X265">x265</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Others</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/CineForm" title="CineForm">CineForm</a></li> <li><a href="/wiki/Cinepak" title="Cinepak">Cinepak</a></li> <li><a href="/wiki/Daala" title="Daala">Daala</a></li> <li><a href="/wiki/Avid_DNxHD" title="Avid DNxHD">DNxHD</a></li> <li><a href="/wiki/Helix_(multimedia_project)" title="Helix (multimedia project)">Helix DNA Producer</a></li> <li><a href="/wiki/Indeo" title="Indeo">Indeo</a></li> <li><a href="/wiki/Libavcodec" title="Libavcodec">libavcodec</a></li> <li><a href="/wiki/Dirac_(video_compression_format)" title="Dirac (video compression format)">Schrödinger (Dirac)</a></li> <li><a href="/wiki/Smart_Bitrate_Control" title="Smart Bitrate Control">SBC</a></li> <li><a href="/wiki/Sorenson_codec" class="mw-redirect" title="Sorenson codec">Sorenson</a></li> <li><a href="/wiki/VP7" class="mw-redirect" title="VP7">VP7</a></li> <li><a href="/wiki/Theora" title="Theora">libtheora</a></li> <li><a href="/wiki/Libvpx" title="Libvpx">libvpx</a></li> <li><a href="/wiki/Windows_Media_Encoder" title="Windows Media Encoder">Windows Media Encoder</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em"><a href="/wiki/Lossless_compression" title="Lossless compression">Lossless</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/FFV1" title="FFV1">FFV1</a></li> <li><a href="/wiki/Huffyuv" title="Huffyuv">Huffyuv</a></li> <li><a href="/wiki/Lagarith" title="Lagarith">Lagarith</a></li> <li><a href="/wiki/MSU_Lossless_Video_Codec" title="MSU Lossless Video Codec">MSU Lossless</a></li> <li><a href="/wiki/YULS" title="YULS">YULS</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li>See also: <a href="/wiki/Template:Compression_methods" title="Template:Compression methods">compression methods</a> and <a href="/wiki/Template:Compression_formats" title="Template:Compression formats">compression formats</a></li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" 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