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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Video codec</span></span>

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<p>A <b>video codec</b> is <a href="Software" title="Software">software</a> or <a href="Computer_hardware" title="Computer hardware">hardware</a> that <a href="Data_compression" title="Data compression">compresses</a> and <a href="Uncompressed_video" title="Uncompressed video">decompresses</a> <a href="Digital_video" title="Digital video">digital video</a>. In the context of video compression, <i><a href="Codec" title="Codec">codec</a></i> is a <a href="Portmanteau" class="mw-redirect" title="Portmanteau">portmanteau</a> of <i>encoder</i> and <i>decoder</i>, while a device that only compresses is typically called an <i><a href="Encoder_(digital)" title="Encoder (digital)">encoder</a></i>, and one that only decompresses is a <i>decoder</i>.

</p><p>The compressed data format usually conforms to a standard <a href="Video_coding_format" title="Video coding format">video coding format</a>. The compression is typically <a href="Lossy" class="mw-redirect" title="Lossy">lossy</a>, meaning that the compressed video lacks some information present in the original video. A consequence of this is that decompressed video has lower quality than the original, uncompressed video because there is insufficient information to accurately reconstruct the original video.

</p><p>There are complex relationships between the <a href="Video_quality" title="Video quality">video quality</a>, the amount of data used to represent the video (determined by the <a href="Bit_rate" title="Bit rate">bit rate</a>), the complexity of the encoding and decoding algorithms, sensitivity to data losses and errors, ease of editing, random access, and end-to-end delay (<a href="Latency_(engineering)" title="Latency (engineering)">latency</a>).

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<div class="mw-heading mw-heading2"><h2 id="History">History</h2></div>

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</style><div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Video_coding_format#History" title="Video coding format">Video coding format § History</a></div>

<p>Historically, video was stored as an analog signal on <a href="Magnetic_tape" title="Magnetic tape">magnetic tape</a>. Around the time when the <a href="Compact_disc" title="Compact disc">compact disc</a> entered the market as a digital-format replacement for analog audio, it became feasible to also store and convey video in digital form. Because of the large amount of storage and bandwidth needed to record and convey raw video, a method was needed to reduce the amount of data used to represent the raw video. Since then, <a href="Engineers" class="mw-redirect" title="Engineers">engineers</a> and <a href="Mathematicians" class="mw-redirect" title="Mathematicians">mathematicians</a> have developed a number of solutions for achieving this goal that involve compressing the digital video data.

</p><p>In 1974, <a href="Discrete_cosine_transform" title="Discrete cosine transform">discrete cosine transform</a> (DCT) compression was introduced by <a href="N._Ahmed" class="mw-redirect" title="N. Ahmed">Nasir Ahmed</a>, T. Natarajan and <a href="K._R._Rao" title="K. R. Rao">K. R. Rao</a>.<sup id="cite_ref-pubDCT_1-0" class="reference"><a href="#cite_note-pubDCT-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-pubRaoYip_2-0" class="reference"><a href="#cite_note-pubRaoYip-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-t81_3-0" class="reference"><a href="#cite_note-t81-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> During the late 1980s, a number of companies began experimenting with DCT <a href="Lossy_compression" title="Lossy compression">lossy compression</a> for video coding, leading to the development of the <a href="H.261" title="H.261">H.261</a> standard.<sup id="cite_ref-Ghanbari_4-0" class="reference"><a href="#cite_note-Ghanbari-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> H.261 was the first practical video coding standard,<sup id="cite_ref-history_5-0" class="reference"><a href="#cite_note-history-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> and was developed by a number of companies, including <a href="Hitachi" title="Hitachi">Hitachi</a>, <a href="PictureTel" title="PictureTel">PictureTel</a>, <a href="Nippon_Telegraph_and_Telephone" title="Nippon Telegraph and Telephone">NTT</a>, <a href="BT_plc" class="mw-redirect" title="BT plc">BT</a>, and <a href="Toshiba" title="Toshiba">Toshiba</a>, among others.<sup id="cite_ref-h261-patents_6-0" class="reference"><a href="#cite_note-h261-patents-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Since H.261, DCT compression has been adopted by all the major video coding standards that followed.<sup id="cite_ref-Ghanbari_4-1" class="reference"><a href="#cite_note-Ghanbari-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup>

</p><p>The most popular <a href="Video_coding_standard" class="mw-redirect" title="Video coding standard">video coding standards</a> used for codecs have been the <a href="MPEG" class="mw-redirect" title="MPEG">MPEG</a> standards. <a href="MPEG-1" title="MPEG-1">MPEG-1</a> was developed by the <a href="Motion_Picture_Experts_Group" class="mw-redirect" title="Motion Picture Experts Group">Motion Picture Experts Group</a> (MPEG) in 1991, and it was designed to compress <a href="VHS" title="VHS">VHS</a>-quality video. It was succeeded in 1994 by <a href="MPEG-2" title="MPEG-2">MPEG-2</a>/<a href="H.262" class="mw-redirect" title="H.262">H.262</a>,<sup id="cite_ref-history_5-1" class="reference"><a href="#cite_note-history-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> which was developed by a number of companies, primarily <a href="Sony" title="Sony">Sony</a>, <a href="Technicolor_SA" class="mw-redirect" title="Technicolor SA">Thomson</a> and <a href="Mitsubishi_Electric" title="Mitsubishi Electric">Mitsubishi Electric</a>.<sup id="cite_ref-mp2-patents_7-0" class="reference"><a href="#cite_note-mp2-patents-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> MPEG-2 became the standard video format for <a href="DVD" title="DVD">DVD</a> and <a href="SD_digital_television" class="mw-redirect" title="SD digital television">SD digital television</a>.<sup id="cite_ref-history_5-2" class="reference"><a href="#cite_note-history-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> In 1999, it was followed by <a href="MPEG-4_Visual" class="mw-redirect" title="MPEG-4 Visual">MPEG-4</a>/<a href="H.263" title="H.263">H.263</a>, which was a major leap forward for video compression technology.<sup id="cite_ref-history_5-3" class="reference"><a href="#cite_note-history-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> It was developed by a number of companies, primarily Mitsubishi Electric, Hitachi and <a href="Panasonic" title="Panasonic">Panasonic</a>.<sup id="cite_ref-mp4-patents_8-0" class="reference"><a href="#cite_note-mp4-patents-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup>

</p><p>The most widely used video coding format, as of 2016, is <a href="H.264/MPEG-4_AVC" class="mw-redirect" title="H.264/MPEG-4 AVC">H.264/MPEG-4 AVC</a>. It was developed in 2003 by a number of organizations, primarily Panasonic, <a href="Godo_kaisha" class="mw-redirect" title="Godo kaisha">Godo Kaisha IP Bridge</a> and <a href="LG_Electronics" title="LG Electronics">LG Electronics</a>.<sup id="cite_ref-avc-patents_9-0" class="reference"><a href="#cite_note-avc-patents-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> H.264 is the main video encoding standard for <a href="Blu-ray_Disc" class="mw-redirect" title="Blu-ray Disc">Blu-ray Discs</a>, and is widely used by streaming internet services such as <a href="YouTube" title="YouTube">YouTube</a>, <a href="Netflix" title="Netflix">Netflix</a>, <a href="Vimeo" title="Vimeo">Vimeo</a>, and <a href="ITunes_Store" title="ITunes Store">iTunes Store</a>, web software such as <a href="Adobe_Flash_Player" title="Adobe Flash Player">Adobe Flash Player</a> and <a href="Microsoft_Silverlight" title="Microsoft Silverlight">Microsoft Silverlight</a>, and various <a href="HDTV" class="mw-redirect" title="HDTV">HDTV</a> broadcasts over terrestrial and satellite television.

</p><p>AVC has been succeeded by <a href="HEVC" class="mw-redirect" title="HEVC">HEVC</a> (H.265), developed in 2013. It is heavily patented, with the majority of patents belonging to <a href="Samsung_Electronics" title="Samsung Electronics">Samsung Electronics</a>, <a href="GE" class="mw-redirect" title="GE">GE</a>, NTT and <a href="JVC_Kenwood" class="mw-redirect" title="JVC Kenwood">JVC Kenwood</a>.<sup id="cite_ref-hevc-patents_10-0" class="reference"><a href="#cite_note-hevc-patents-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-hevcadvance_11-0" class="reference"><a href="#cite_note-hevcadvance-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> The adoption of HEVC has been hampered by its complex licensing structure. HEVC is in turn succeeded by <a href="Versatile_Video_Coding" title="Versatile Video Coding">Versatile Video Coding</a> (VVC).

</p><p>There are also the open and free <a href="VP8" title="VP8">VP8</a>, <a href="VP9" title="VP9">VP9</a> and <a href="AV1" title="AV1">AV1</a> video coding formats, used by YouTube, all of which were developed with involvement from <a href="Google" title="Google">Google</a>.

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<div class="mw-heading mw-heading2"><h2 id="Applications">Applications</h2></div>

<p>Video codecs are used in DVD players, <a href="Internet_video" title="Internet video">Internet video</a>, <a href="Video_on_demand" title="Video on demand">video on demand</a>, <a href="Digital_cable" title="Digital cable">digital cable</a>, <a href="Digital_terrestrial_television" title="Digital terrestrial television">digital terrestrial television</a>, <a href="Videotelephony" title="Videotelephony">videotelephony</a> and a variety of other applications. In particular, they are widely used in applications that record or transmit video, which may not be feasible with the high data volumes and bandwidths of uncompressed video. For example, they are used in <a href="Operating_theater" title="Operating theater">operating theaters</a> to record surgical operations, in <a href="IP_camera" title="IP camera">IP cameras</a> in security systems, and in <a href="Remotely_operated_underwater_vehicle" title="Remotely operated underwater vehicle">remotely operated underwater vehicles</a> and <a href="Unmanned_aerial_vehicle" title="Unmanned aerial vehicle">unmanned aerial vehicles</a>. Any video stream or file can be encoded using a wide variety of live video format options. Here are some of the H.264 encoder settings that need to be set when streaming to an HTML5 video player.<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>

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<div class="mw-heading mw-heading2"><h2 id="Video_codec_design">Video codec design</h2></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Video_coding_format" title="Video coding format">Video coding format</a></div>

<p>Video codecs seek to represent a fundamentally analog data set in a digital format. Because of the design of analog video signals, which represent <a href="Luminance_(video)" class="mw-redirect" title="Luminance (video)">luminance</a> (luma) and <a href="Chrominance" title="Chrominance">color information</a> (chrominance, chroma) separately, a common first step in image compression in codec design is to represent and store the image in a <a href="YCbCr" title="YCbCr">YCbCr</a> color space. The conversion to YCbCr provides two benefits: first, it improves compressibility by providing decorrelation of the color signals; and second, it separates the luma signal, which is perceptually much more important, from the chroma signal, which is less perceptually important and which can be represented at lower resolution using <a href="Chroma_subsampling" title="Chroma subsampling">chroma subsampling</a> to achieve more efficient data compression. It is common to represent the ratios of information stored in these different channels in the following way Y:Cb:Cr. Different codecs use different chroma subsampling ratios as appropriate to their compression needs. Video compression schemes for Web and DVD make use of a 4:2:1 color sampling pattern, and the <a href="DV_(video_format)" title="DV (video format)">DV</a> standard uses 4:1:1 sampling ratios. Professional video codecs designed to function at much higher bitrates and to record a greater amount of color information for post-production manipulation sample in 4:2:2 and 4:4:4 ratios. Examples of these codecs include Panasonic's DVCPRO50 and DVCPROHD codecs (4:2:2), Sony's HDCAM-SR (4:4:4), Panasonic's HDD5 (4:2:2), <a href="Apple_Inc." title="Apple Inc.">Apple</a>'s Prores HQ 422 (4:2:2).<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup>

</p><p>It is also worth noting that video codecs can operate in RGB space as well. These codecs tend not to sample the red, green, and blue channels in different ratios, since there is less perceptual motivation for doing so—just the blue channel could be undersampled.

</p><p>Some amount of spatial and temporal <a href="Downsampling" class="mw-redirect" title="Downsampling">downsampling</a> may also be used to reduce the raw data rate before the basic encoding process. The most popular encoding transform is the 8x8 DCT. Codecs that make use of a <a href="Wavelet" title="Wavelet">wavelet</a> transform are also entering the market, especially in camera workflows that involve dealing with <a href="Raw_image_format" title="Raw image format">RAW</a> image formatting in motion sequences. This process involves representing the video image as a set of <a href="Macroblocks" class="mw-redirect" title="Macroblocks">macroblocks</a>. For more information about this critical facet of video codec design, see <a href="B-frames" class="mw-redirect" title="B-frames">B-frames</a>.<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>

</p><p>The output of the transform is first <a href="Quantization_(image_processing)" title="Quantization (image processing)">quantized</a>, then <a href="Entropy_encoding" class="mw-redirect" title="Entropy encoding">entropy encoding</a> is applied to the quantized values. When a DCT has been used, the coefficients are typically scanned using a zig-zag scan order, and the entropy coding typically combines a number of consecutive zero-valued quantized coefficients with the value of the next non-zero quantized coefficient into a single symbol and also has special ways of indicating when all of the remaining quantized coefficient values are equal to zero. The entropy coding method typically uses <a href="Variable-length_code" title="Variable-length code">variable-length coding tables</a>. Some encoders compress the video in a multiple-step process called <i>n-pass</i> encoding (e.g. 2-pass), which performs a slower but potentially higher quality compression.

</p><p>The decoding process consists of performing, to the extent possible, an inversion of each stage of the encoding process.<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 one stage that cannot be exactly inverted is the quantization stage. There, a best-effort approximation of inversion is performed. This part of the process is often called <i>inverse quantization</i> or <i>dequantization</i>, although quantization is an inherently non-invertible process.

</p><p>Video codec designs are usually standardized or eventually become standardized—i.e., specified precisely in a published document. However, only the decoding process need be standardized to enable interoperability. The encoding process is typically not specified at all in a standard, and implementers are free to design their encoder however they want, as long as the video can be decoded in the specified manner. For this reason, the quality of the video produced by decoding the results of different encoders that use the same video codec standard can vary dramatically from one encoder implementation to another.

</p>

<div class="mw-heading mw-heading2"><h2 id="Commonly_used_video_codecs">Commonly used video codecs</h2></div>

<div role="note" class="hatnote navigation-not-searchable">Main article: <a href="List_of_codecs#Video_compression_formats" title="List of codecs">List of codecs § Video compression formats</a></div>

<p>A variety of video compression formats can be implemented on PCs and in consumer electronics equipment. It is therefore possible for multiple codecs to be available in the same product, reducing the need to choose a single dominant video compression format to achieve <a href="Interoperability" title="Interoperability">interoperability</a>.

</p><p>Standard <a href="Video_compression_format" class="mw-redirect" title="Video compression format">video compression formats</a> can be supported by multiple encoder and decoder implementations from multiple sources. For example, video encoded with a standard <a href="MPEG-4_Part_2" title="MPEG-4 Part 2">MPEG-4 Part 2</a> codec such as <a href="Xvid" title="Xvid">Xvid</a> can be decoded using any other standard <a href="MPEG-4_Part_2" title="MPEG-4 Part 2">MPEG-4 Part 2</a> codec such as FFmpeg MPEG-4 or DivX Pro Codec, because they all use the same video format.

</p><p>Codecs have their qualities and drawbacks. <a href="Comparison_of_video_codecs" title="Comparison of video codecs">Comparisons</a> are frequently published. The trade-off between compression power, speed, and fidelity (including <a href="Compression_artifact" title="Compression artifact">artifacts</a>) is usually considered the most important figure of technical merit.

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<div class="mw-heading mw-heading2"><h2 id="Codec_packs">Codec packs</h2></div>

<p>Online video material is encoded by a variety of codecs, and this has led to the availability of codec packs — a pre-assembled set of commonly used codecs combined with an installer available as a software package for PCs, such as <a href="K-Lite_Codec_Pack" title="K-Lite Codec Pack">K-Lite Codec Pack</a>, <a href="Perian" title="Perian">Perian</a> and <a href="Combined_Community_Codec_Pack" title="Combined Community Codec Pack">Combined Community Codec Pack</a>.

</p>

<li><a href="Comparison_of_video_codecs" title="Comparison of video codecs">Comparison of video codecs</a></li>

<li><a href="Data_compression#Video" title="Data compression">Data compression § Video</a></li>

<li><a href="Display_resolution" title="Display resolution">Display resolution</a></li>

<li><a href="Frame_rate" title="Frame rate">Frame rate</a></li>

<li><a href="List_of_open-source_codecs" title="List of open-source codecs">List of open-source codecs</a></li>

<li><a href="Multiplexing" title="Multiplexing">Multiplexing</a></li>

<li><a href="Sampling_rate" class="mw-redirect" title="Sampling rate">Sampling rate</a></li>

<li><a href="Subjective_video_quality" title="Subjective video quality">Subjective video quality</a></li>

<li><a href="Transcoding" title="Transcoding">Transcoding</a></li>

<li><a href="Video_quality" title="Video quality">Video quality</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><cite id="CITEREFAhmedNatarajanRao1974" class="citation cs2"><a href="N._Ahmed" class="mw-redirect" title="N. Ahmed">Ahmed, Nasir</a>; Natarajan, T.; Rao, K. R. (January 1974), "Discrete Cosine Transform", <i>IEEE Transactions on Computers</i>, <b>C-23</b> (1): <span class="nowrap">90–</span>93, <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FT-C.1974.223784">10.1109/T-C.1974.223784</a>, <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:149806273">149806273</a></cite></span>

</li>

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<li id="cite_note-t81-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-t81_3-0">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.w3.org/Graphics/JPEG/itu-t81.pdf">"T.81 – DIGITAL COMPRESSION AND CODING OF CONTINUOUS-TONE STILL IMAGES – REQUIREMENTS AND GUIDELINES"</a> <span class="cs1-format">(PDF)</span>. CCITT. September 1992<span class="reference-accessdate">. Retrieved <span class="nowrap">12 July</span> 2019</span>.</cite></span>

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<li id="cite_note-history-5"><span class="mw-cite-backlink">^ <a href="#cite_ref-history_5-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-history_5-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-history_5-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-history_5-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.real.com/resources/digital-video-file-formats/">"The History of Video File Formats Infographic — RealPlayer"</a>. 22 April 2012.</cite></span>

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<li id="cite_note-hevcadvance-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-hevcadvance_11-0">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20200824174620/https://www.hevcadvance.com/licensors/">"HEVC Advance Patent List"</a>. <i>HEVC Advance</i>. Archived from <a rel="nofollow" class="external text" href="https://www.hevcadvance.com/licensors/">the original</a> on 24 August 2020<span class="reference-accessdate">. Retrieved <span class="nowrap">6 July</span> 2019</span>.</cite></span>

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</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

<ul><li><a rel="nofollow" class="external text" href="http://ivms.stanford.edu/~dsc/wzcodingvideo">Wyner-Ziv Coding of Video</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20110930024946/http://ivms.stanford.edu/~dsc/wzcodingvideo">Archived</a> 2011-09-30 at the <a href="Wayback_Machine" title="Wayback Machine">Wayback Machine</a> describes another algorithm for video compression that performs close to the <a href="Slepian%E2%80%93Wolf_bound" class="mw-redirect" title="Slepian–Wolf bound">Slepian–Wolf bound</a> (with links to source code).</li>

<li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20120828085725/http://support.amd.com/us/gpudownload/windows/Pages/eyespeed_downloads.aspx">AMD Media Codecs</a>—optional download (formerly called <a href="ATI_Avivo" title="ATI Avivo">ATI Avivo</a>)</li></ul>

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</style><div id="Multimedia_compression_and_container_formats462" style="font-size:114%;margin:0 4em"><a href="Multimedia" title="Multimedia">Multimedia</a> <a href="Data_compression" title="Data compression">compression</a> and <a href="Container_format_(computing)" class="mw-redirect" title="Container format (computing)">container</a> formats</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Video_coding_format" title="Video coding format">Video<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="International_Organization_for_Standardization" title="International Organization for Standardization">ISO</a>, <a href="International_Electrotechnical_Commission" title="International Electrotechnical Commission">IEC</a>, <br><a href="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">

<li><a href="Motion_JPEG" title="Motion JPEG">MJPEG</a></li>

<li><a href="Motion_JPEG_2000" title="Motion JPEG 2000">Motion JPEG 2000</a></li>

<li>MPEG-I

<li><a href="LCEVC" title="LCEVC">Part 2 / LCEVC</a></li></ul></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="ITU-T" title="ITU-T">ITU-T</a>, <a href="Video_Coding_Experts_Group" title="Video Coding Experts Group">VCEG</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em">

<li>H.267 / Enhanced Compression Model</li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="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">

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="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="On2_Technologies#TrueMotion_S" title="On2 Technologies">TrueMotion S</a></li>

</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">

<li><a href="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>

</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="Apple_Video" title="Apple Video">Apple Video</a></li>

<li><a href="Cinepak" title="Cinepak">Cinepak</a></li>

<li><a href="Daala" title="Daala">Daala</a></li>

<li><a href="Huffyuv" title="Huffyuv">Huffyuv</a></li>

<li><a href="Indeo" title="Indeo">Indeo</a></li>

<li><a href="Lagarith" title="Lagarith">Lagarith</a></li>

<li><a href="Microsoft_Video_1" title="Microsoft Video 1">Microsoft Video 1</a></li>

<li><a href="MSU_Lossless_Video_Codec" title="MSU Lossless Video Codec">MSU Lossless</a></li>

<li><a href="OMS_Video" title="OMS Video">OMS Video</a></li>

<li><a href="Pixlet" title="Pixlet">Pixlet</a></li>

<li><a href="Apple_ProRes" title="Apple ProRes">ProRes</a>

<li>QuickTime

<ul><li><a href="QuickTime_Animation" title="QuickTime Animation">Animation</a></li>

<li><a href="QuickTime_Graphics" title="QuickTime Graphics">Graphics</a></li></ul></li>

<li><a href="RealVideo" title="RealVideo">RealVideo</a></li>

<li><a href="RTVideo" title="RTVideo">RTVideo</a></li>

<li><a href="SheerVideo" title="SheerVideo">SheerVideo</a></li>

<li><a href="Smacker_video" title="Smacker video">Smacker</a></li>

<li><a href="Sorenson_Media" title="Sorenson Media">Sorenson Video/Spark</a></li>

<li><a href="Theora" title="Theora">Theora</a></li>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="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="International_Organization_for_Standardization" title="International Organization for Standardization">ISO</a>, <a href="International_Electrotechnical_Commission" title="International Electrotechnical Commission">IEC</a>,<br> <a href="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="MPEG-1_Audio_Layer_II" title="MPEG-1 Audio Layer II">MPEG-1 Layer II</a>

<ul><li><a href="MPEG_Multichannel" title="MPEG Multichannel">Multichannel</a></li></ul></li>

<li><a href="MPEG-1_Audio_Layer_I" title="MPEG-1 Audio Layer I">MPEG-1 Layer I</a></li>

<li><a href="MP3" title="MP3">MPEG-1 Layer III (MP3)</a></li>

<li><a href="MPEG_Surround" title="MPEG Surround">MPEG Surround</a></li>

<li><a href="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="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">

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="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">

<li><a href="Speex" title="Speex">Speex</a></li>

<li><a href="Vorbis" title="Vorbis">Vorbis</a></li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="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">

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="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">

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="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">

<li><a href="Audio_Video_Standard#Second_generation" title="Audio Video Standard">AVS2 P3</a>(GB/T 33475.3)

<ul><li>Audio Vivid(GY/T 363)</li></ul></li>

</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="Algebraic_code-excited_linear_prediction" title="Algebraic code-excited linear prediction">ACELP</a></li>

<li><a href="Adaptive_Transform_Acoustic_Coding" class="mw-redirect" title="Adaptive Transform Acoustic Coding">ATRAC</a></li>

<li><a href="Codec_2" title="Codec 2">Codec 2</a></li>

<li><a href="Monkey's_Audio" title="Monkey's Audio">Monkey's Audio</a></li>

<li><a href="Musepack" title="Musepack">Musepack</a></li>

<li><a href="OptimFROG" title="OptimFROG">OptimFROG</a></li>

<li><a href="Qualcomm_code-excited_linear_prediction" title="Qualcomm code-excited linear prediction">QCELP</a></li>

<li><a href="Relaxed_code-excited_linear_prediction" title="Relaxed code-excited linear prediction">RCELP</a></li>

<li><a href="RealAudio" title="RealAudio">RealAudio</a></li>

<li><a href="Siren_(codec)" title="Siren (codec)">Siren</a></li>

<li><a href="SVOPC" title="SVOPC">SVOPC</a></li>

<li>TTA

<ul><li>True Audio</li></ul></li>

<li><a href="TwinVQ" title="TwinVQ">TwinVQ</a></li>

<li><a href="Vector_sum_excited_linear_prediction" title="Vector sum excited linear prediction">VSELP</a></li>

<li><a href="WavPack" title="WavPack">WavPack</a></li>

<li><a href="AptX#aptX_Low_Latency" title="AptX">aptX Low Latency</a></li>

<li><a href="AptX#aptX_Adaptive" title="AptX">aptX Adaptive</a></li>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="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="International_Electrotechnical_Commission" title="International Electrotechnical Commission">IEC</a>, <a href="International_Organization_for_Standardization" title="International Organization for Standardization">ISO</a>, <a href="Internet_Engineering_Task_Force" title="Internet Engineering Task Force">IETF</a>, <br><a href="World_Wide_Web_Consortium" title="World Wide Web Consortium">W3C</a>, <a href="ITU-T" title="ITU-T">ITU-T</a>, <a href="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="Group_4_compression" title="Group 4 compression">CCITT Group 4</a></li>

</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">

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="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="International_Organization_for_Standardization" title="International Organization for Standardization">ISO</a>, <a href="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">

<li><a href="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="Motion_JPEG_2000" title="Motion JPEG 2000">Motion JPEG 2000</a></li>

<li><a href="MPEG_media_transport" title="MPEG media transport">MPEG media transport</a></li></ul>

<li><a href="Matroska" title="Matroska">Matroska</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="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">

</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="Smacker_video" title="Smacker video">Smacker</a></li></ul></li>

<li><a href="DivX#DivX_Media_Format_(DMF)" title="DivX">DivX Media Format</a></li>

<li><a href="Flash_Video" title="Flash Video">Flash Video</a></li>

<li><a href="Matroska" title="Matroska">Matroska</a>

<li><a href="QuickTime_File_Format" title="QuickTime File Format">QuickTime File Format</a></li>

<li><a href="RatDVD" title="RatDVD">RatDVD</a></li>

<li><a href="RealMedia" title="RealMedia">RealMedia</a></li>

</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="NETVC" title="NETVC">NETVC</a></li>

<li><a href="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="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="Entropy_encoding" class="mw-redirect" title="Entropy encoding">Entropy</a>

<ul><li><a href="Arithmetic_coding" title="Arithmetic coding">Arithmetic</a></li>

<li><a href="Huffman_coding" title="Huffman coding">Huffman</a></li>

<li><a href="Modified_Huffman_coding" title="Modified Huffman coding">Modified</a></li></ul></li>

<ul><li><a href="Algebraic_code-excited_linear_prediction" title="Algebraic code-excited linear prediction">ACELP</a></li>

<li><a href="Lossless_compression" title="Lossless compression">Lossless</a></li>

<li><a href="Lossy_compression" title="Lossy compression">Lossy</a></li>

<ul><li><a href="DEFLATE" class="mw-redirect" title="DEFLATE">DEFLATE</a></li>

<li><a href="Adaptive_differential_pulse-code_modulation" title="Adaptive differential pulse-code modulation">ADPCM</a></li>

<li><a href="Transform_coding" title="Transform coding">Transforms</a>

<li><a href="Wavelet" title="Wavelet">Wavelet</a>

<ul><li><a href="Daubechies_wavelet" title="Daubechies wavelet">Daubechies</a></li>

</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="Comparison_of_audio_coding_formats" title="Comparison of audio coding formats">Comparison of audio coding formats</a></li>

<li><a href="Comparison_of_video_codecs" title="Comparison of video codecs">Comparison of video codecs</a></li>

<li><a href="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 Compression methods for techniques and Compression software for codecs</div></td></tr></tbody></table></div>

<div class="navbox-styles"></div><div role="navigation" class="navbox" aria-labelledby="Data_compression_methods241" 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"><div id="Data_compression_methods241" style="font-size:114%;margin:0 4em"><a href="Data_compression" title="Data compression">Data compression</a> methods</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Lossless_compression" title="Lossless compression">Lossless</a><br>type</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:1%"><a href="Entropy_coding" title="Entropy coding">Entropy</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="Adaptive_coding" title="Adaptive coding">Adaptive coding</a></li>

<li><a href="Arithmetic_coding" title="Arithmetic coding">Arithmetic</a></li>

<li><a href="Asymmetric_numeral_systems" title="Asymmetric numeral systems">Asymmetric numeral systems</a></li>

<li><a href="Golomb_coding" title="Golomb coding">Golomb</a></li>

<li><a href="Huffman_coding" title="Huffman coding">Huffman</a>

<ul><li><a href="Adaptive_Huffman_coding" title="Adaptive Huffman coding">Adaptive</a></li>

<li><a href="Canonical_Huffman_code" title="Canonical Huffman code">Canonical</a></li>

<li><a href="Modified_Huffman_coding" title="Modified Huffman coding">Modified</a></li></ul></li>

<li><a href="Range_coding" title="Range coding">Range</a></li>

<li><a href="Shannon_coding" title="Shannon coding">Shannon</a></li>

<li><a href="Shannon%E2%80%93Fano_coding" title="Shannon–Fano coding">Shannon–Fano</a></li>

<li><a href="Shannon%E2%80%93Fano%E2%80%93Elias_coding" title="Shannon–Fano–Elias coding">Shannon–Fano–Elias</a></li>

<li><a href="Tunstall_coding" title="Tunstall coding">Tunstall</a></li>

<li><a href="Unary_coding" title="Unary coding">Unary</a></li>

<li><a href="Universal_code_(data_compression)" title="Universal code (data compression)">Universal</a>

<ul><li><a href="Exponential-Golomb_coding" title="Exponential-Golomb coding">Exp-Golomb</a></li>

<li><a href="Fibonacci_coding" title="Fibonacci coding">Fibonacci</a></li>

<li><a href="Elias_gamma_coding" title="Elias gamma coding">Gamma</a></li>

<li><a href="Levenshtein_coding" title="Levenshtein coding">Levenshtein</a></li></ul></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Dictionary_coder" title="Dictionary coder">Dictionary</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="Byte-pair_encoding" title="Byte-pair encoding">Byte-pair encoding</a></li>

<li><a href="LZ77_and_LZ78" title="LZ77 and LZ78">Lempel–Ziv</a>

<li><a href="Snappy_(compression)" title="Snappy (compression)">Snappy</a></li></ul></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Delta_encoding" title="Delta encoding">Delta</a>

<ul><li><a href="Incremental_encoding" title="Incremental encoding">Incremental</a></li></ul></li>

<li><a href="Grammar-based_code" title="Grammar-based code">Grammar</a>

<li><a href="Sequitur_algorithm" title="Sequitur algorithm">Sequitur</a></li></ul></li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Hybrid</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li>LZ77 + Huffman

<ul><li><a href="Deflate" title="Deflate">Deflate</a></li>

<li>LZ77 + ANS

<ul><li><a href="LZFSE" title="LZFSE">LZFSE</a></li></ul></li>

<li>LZ77 + Huffman + ANS

<ul><li><a href="Zstd" title="Zstd">Zstandard</a></li></ul></li>

<li>LZ77 + Huffman + context

<ul><li><a href="Brotli" title="Brotli">Brotli</a></li></ul></li>

<li>LZSS + Huffman

<li>LZ77 + Range

<li>LZHAM</li></ul></li>

<li>RLE + BWT + MTF + Huffman

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Lossy_compression" title="Lossy compression">Lossy</a><br>type</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:1%"><a href="Transform_coding" title="Transform coding">Transform</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="Discrete_cosine_transform" title="Discrete cosine transform">Discrete cosine transform</a>

<li><a href="Wavelet_transform" title="Wavelet transform">Wavelet</a>

<ul><li><a href="Daubechies_wavelet" title="Daubechies wavelet">Daubechies</a></li>

<li><a href="Set_partitioning_in_hierarchical_trees" title="Set partitioning in hierarchical trees">SPIHT</a></li></ul></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Predictive</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="Adaptive_differential_pulse-code_modulation" title="Adaptive differential pulse-code modulation">ADPCM</a></li></ul></li>

<ul><li><a href="Algebraic_code-excited_linear_prediction" title="Algebraic code-excited linear prediction">ACELP</a></li>

<li>Motion

<ul><li><a href="Motion_compensation" title="Motion compensation">Compensation</a></li>

<li><a href="Motion_estimation" title="Motion estimation">Estimation</a></li>

<li><a href="Motion_vector" class="mw-redirect" title="Motion vector">Vector</a></li></ul></li>

<li><a href="Psychoacoustics" title="Psychoacoustics">Psychoacoustic</a></li></ul>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Data_compression#Audio" title="Data compression">Audio</a></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:1%">Concepts</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Companding" title="Companding">Companding</a></li>

<li><a href="Convolution" title="Convolution">Convolution</a></li>

<li><a href="Dynamic_range" title="Dynamic range">Dynamic range</a></li>

<li><a href="Latency_(audio)" title="Latency (audio)">Latency</a></li>

<li><a href="Nyquist%E2%80%93Shannon_sampling_theorem" title="Nyquist–Shannon sampling theorem">Nyquist–Shannon theorem</a></li>

<li><a href="Sampling_(signal_processing)" title="Sampling (signal processing)">Sampling</a></li>

<li><a href="Silence_compression" title="Silence compression">Silence compression</a></li>

<li><a href="Sound_quality" title="Sound quality">Sound quality</a></li>

<li><a href="Speech_coding" title="Speech coding">Speech coding</a></li>

<li><a href="Sub-band_coding" title="Sub-band coding">Sub-band coding</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Audio_codec" title="Audio codec">Codec</a><br>parts</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="Adaptive_differential_pulse-code_modulation" title="Adaptive differential pulse-code modulation">ADPCM</a></li>

<ul><li><a href="Algebraic_code-excited_linear_prediction" title="Algebraic code-excited linear prediction">ACELP</a></li>

<li><a href="Psychoacoustics" title="Psychoacoustics">Psychoacoustic model</a></li></ul>

<ul><li><a href="Chroma_subsampling" title="Chroma subsampling">Chroma subsampling</a></li>

<li><a href="Coding_tree_unit" title="Coding tree unit">Coding tree unit</a></li>

<li><a href="Color_space" title="Color space">Color space</a></li>

<li><a href="Compression_artifact" title="Compression artifact">Compression artifact</a></li>

<li><a href="Image_resolution" title="Image resolution">Image resolution</a></li>

<li><a href="Macroblock" title="Macroblock">Macroblock</a></li>

<li><a href="Pixel" title="Pixel">Pixel</a></li>

<li><a href="Quantization_(image_processing)" title="Quantization (image processing)">Quantization</a></li>

<li><a href="Standard_test_image" title="Standard test image">Standard test image</a></li>

<li><a href="Texture_compression" title="Texture compression">Texture compression</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Methods</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="Chain_code" title="Chain code">Chain code</a></li>

<li><a href="Deflate" title="Deflate">Deflate</a></li>

<li><a href="Fractal_compression" title="Fractal compression">Fractal</a></li>

<li><a href="Wavelet_transform" title="Wavelet transform">Wavelet</a>

<ul><li><a href="Daubechies_wavelet" title="Daubechies wavelet">Daubechies</a></li>

<li><a href="Set_partitioning_in_hierarchical_trees" title="Set partitioning in hierarchical trees">SPIHT</a></li></ul></li></ul>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Data_compression#Video" title="Data compression">Video</a></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:1%">Concepts</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Display_resolution" title="Display resolution">Display resolution</a></li>

<li><a href="Film_frame" title="Film frame">Frame</a></li>

<li><a href="Frame_rate" title="Frame rate">Frame rate</a></li>

<li><a href="Video_compression_picture_types" title="Video compression picture types">Frame types</a></li>

<li><a href="Interlaced_video" title="Interlaced video">Interlace</a></li>

<li><a href="Video#Characteristics_of_video_streams" title="Video">Video characteristics</a></li>

<li><a href="Video_quality" title="Video quality">Video quality</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><br>parts</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Deblocking_filter" title="Deblocking filter">Deblocking filter</a></li>

<li><a href="Lapped_transform" title="Lapped transform">Lapped transform</a></li>

<li>Motion

<ul><li><a href="Motion_compensation" title="Motion compensation">Compensation</a></li>

<li><a href="Motion_estimation" title="Motion estimation">Estimation</a></li>

<li><a href="Motion_vector" class="mw-redirect" title="Motion vector">Vector</a></li></ul></li>

<li><a href="Wavelet_transform" title="Wavelet transform">Wavelet</a>

<ul><li><a href="Daubechies_wavelet" title="Daubechies wavelet">Daubechies</a></li>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Information_theory" title="Information theory">Theory</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="Compressed_data_structure" title="Compressed data structure">Compressed data structures</a>

<ul><li><a href="Compressed_suffix_array" title="Compressed suffix array">Compressed suffix array</a></li>

<li><a href="FM-index" title="FM-index">FM-index</a></li></ul></li>

<li><a href="Entropy_(information_theory)" title="Entropy (information theory)">Entropy</a></li>

<li><a href="Information_theory" title="Information theory">Information theory</a>

<ul><li><a href="Timeline_of_information_theory" title="Timeline of information theory">Timeline</a></li></ul></li>

<li><a href="Kolmogorov_complexity" title="Kolmogorov complexity">Kolmogorov complexity</a></li>

<li><a href="Prefix_code" title="Prefix code">Prefix code</a></li>

<li><a href="Quantization_(signal_processing)" title="Quantization (signal processing)">Quantization</a></li>

<li><a href="Rate%E2%80%93distortion_theory" title="Rate–distortion theory">Rate–distortion</a></li>

<li><a href="Redundancy_(information_theory)" title="Redundancy (information theory)">Redundancy</a></li>

<li><a href="Data_compression_symmetry" title="Data compression symmetry">Symmetry</a></li>

<li><a href="Smallest_grammar_problem" title="Smallest grammar problem">Smallest grammar problem</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Community</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="Hutter_Prize" title="Hutter Prize">Hutter Prize</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">People</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="Mark_Adler" title="Mark Adler">Mark Adler</a></li>

</div></td></tr></tbody></table></div></div><div><div class="zim-footer">

This article is issued from <a class="external text" title="Last edited on 2025-07-17" href="https://en.wikipedia.org/wiki/?title=Video_codec&oldid=1300901685">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

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