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Advanced Video Coding (AVC), also referred to as H.264 or MPEG-4 Part 10, is a
video compression standard A video coding format (or sometimes video compression format) is a content representation format for storage or transmission of digital video content (such as in a data file or bitstream). It typically uses a standardized video compression algori ...
based on block-oriented, motion-compensated coding. It is by far the most commonly used format for the recording, compression, and distribution of video content, used by 91% of video industry developers . It supports resolutions up to and including
8K UHD 8K resolution refers to an image or display resolution with a width of approximately 8,000 pixels. 8K UHD () is the highest resolution defined in the Rec. 2020 (UHDTV) standard. 8K display resolution is the successor to 4K resolution. TV manuf ...
. The intent of the H.264/AVC project was to create a standard capable of providing good video quality at substantially lower
bit rate In telecommunications and computing, bit rate (bitrate or as a variable ''R'') is the number of bits that are conveyed or processed per unit of time. The bit rate is expressed in the unit bit per second (symbol: bit/s), often in conjunction w ...
s than previous standards (i.e., half or less the bit rate of
MPEG-2 MPEG-2 (a.k.a. H.222/H.262 as was defined by the ITU) is a standard for "the generic video coding format, coding of moving pictures and associated audio information". It describes a combination of Lossy compression, lossy video compression and ...
,
H.263 H.263 is a video compression standard originally designed as a low-bit-rate compressed format for videotelephony. It was standardized by the ITU-T Video Coding Experts Group (VCEG) in a project ending in 1995/1996. It is a member of the H.26x fam ...
, or
MPEG-4 Part 2 MPEG-4 Part 2, MPEG-4 Visual (formally ISO/IEC 14496-2) is a video compression format developed by the Moving Picture Experts Group (MPEG). It belongs to the MPEG-4 ISO/IEC standards. It uses block-wise motion compensation and a discrete cosine tr ...
), without increasing the complexity of design so much that it would be impractical or excessively expensive to implement. This was achieved with features such as a reduced-complexity integer discrete cosine transform (integer DCT), variable block-size segmentation, and multi-picture inter-picture prediction. An additional goal was to provide enough flexibility to allow the standard to be applied to a wide variety of applications on a wide variety of networks and systems, including low and high bit rates, low and high resolution video,
broadcast Broadcasting is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, but typically one using the electromagnetic spectrum ( radio waves), in a one-to-many model. Broadcasting began ...
,
DVD The DVD (common abbreviation for Digital Video Disc or Digital Versatile Disc) is a digital optical disc data storage format. It was invented and developed in 1995 and first released on November 1, 1996, in Japan. The medium can store any kin ...
storage, RTP/ IP packet networks, and
ITU-T The ITU Telecommunication Standardization Sector (ITU-T) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU). It is responsible for coordinating standards for telecommunications and Information Commu ...
multimedia
telephony Telephony ( ) is the field of technology involving the development, application, and deployment of telecommunication services for the purpose of electronic transmission of voice, fax, or data, between distant parties. The history of telephony is i ...
systems. The H.264 standard can be viewed as a "family of standards" composed of a number of different profiles, although its "High profile" is by far the most commonly used format. A specific decoder decodes at least one, but not necessarily all profiles. The standard describes the format of the encoded data and how the data is decoded, but it does not specify algorithms for encoding video that is left open as a matter for encoder designers to select for themselves, and a wide variety of encoding schemes have been developed. H.264 is typically used for
lossy compression In information technology, lossy compression or irreversible compression is the class of data compression methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data size ...
, although it is also possible to create truly lossless-coded regions within lossy-coded pictures or to support rare use cases for which the entire encoding is lossless. H.264 was standardized by the
ITU-T The ITU Telecommunication Standardization Sector (ITU-T) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU). It is responsible for coordinating standards for telecommunications and Information Commu ...
Video Coding Experts Group The Video Coding Experts Group or Visual Coding Experts Group (VCEG, also known as Question 6) is a working group of the ITU Telecommunication Standardization Sector (ITU-T) concerned with standards for compression coding of video, images, audio, ...
(VCEG) of Study Group 16 together with the
ISO/IEC JTC 1 ISO/IEC JTC 1, entitled "Information technology", is a joint technical committee (JTC) of the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). Its purpose is to develop, maintain and pr ...
Moving Picture Experts Group The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by ISO and IEC that sets standards for media coding, including compression coding of audio, video, graphics, and genomic data; and transmission and f ...
(MPEG). The project partnership effort is known as the Joint Video Team (JVT). The ITU-T H.264 standard and the ISO/IEC
MPEG-4 MPEG-4 is a group of international standards for the compression of digital audio and visual data, multimedia systems, and file storage formats. It was originally introduced in late 1998 as a group of audio and video coding formats and related tec ...
 AVC standard (formally, ISO/IEC 14496-10 – MPEG-4 Part 10, Advanced Video Coding) are jointly maintained so that they have identical technical content. The final drafting work on the first version of the standard was completed in May 2003, and various extensions of its capabilities have been added in subsequent editions.
High Efficiency Video Coding High Efficiency Video Coding (HEVC), also known as H.265 and MPEG-H Part 2, is a video compression standard designed as part of the MPEG-H project as a successor to the widely used Advanced Video Coding (AVC, H.264, or MPEG-4 Part 10). In compar ...
(HEVC), a.k.a. H.265 and MPEG-H Part 2 is a successor to H.264/MPEG-4 AVC developed by the same organizations, while earlier standards are still in common use. H.264 is perhaps best known as being the most commonly used video encoding format on
Blu-ray Disc The Blu-ray Disc (BD), often known simply as Blu-ray, is a Digital media, digital optical disc data storage format. It was invented and developed in 2005 and released on June 20, 2006 worldwide. It is designed to supersede the DVD format, and c ...
s. It is also widely used by streaming Internet sources, such as videos from
Netflix Netflix, Inc. is an American subscription video on-demand over-the-top streaming service and production company based in Los Gatos, California. Founded in 1997 by Reed Hastings and Marc Randolph in Scotts Valley, California, it offers a fil ...
,
Hulu Hulu () is an American subscription streaming service majority-owned by The Walt Disney Company, with Comcast's NBCUniversal holding a minority stake. It was launched on October 29, 2007 and it offers a library of films and television serie ...
,
Amazon Prime Video Amazon Prime Video, also known simply as Prime Video, is an American Video on demand#Subscription models, subscription video on-demand Over-the-top media service, over-the-top Streaming media, streaming and Renting, rental service of Amazon (c ...
,
Vimeo Vimeo, Inc. () is an American video hosting, sharing, and services platform provider headquartered in New York City. Vimeo focuses on the delivery of high-definition video across a range of devices. Vimeo's business model is through software as ...
,
YouTube YouTube is a global online video platform, online video sharing and social media, social media platform headquartered in San Bruno, California. It was launched on February 14, 2005, by Steve Chen, Chad Hurley, and Jawed Karim. It is owned by ...
, and the
iTunes Store The iTunes Store is a digital media store operated by Apple Inc. It opened on April 28, 2003, as a result of Steve Jobs' push to open a digital marketplace for music. As of April 2020, iTunes offered 60 million songs, 2.2 million apps, 25,00 ...
, Web software such as the
Adobe Flash Player Adobe Flash Player (known in Internet Explorer, Firefox, and Google Chrome as Shockwave Flash) is Software, computer software for viewing multimedia contents, executing rich Internet applications, and streaming media, streaming audio and vide ...
and
Microsoft Silverlight Microsoft Silverlight is a discontinued application framework designed for writing and running rich web applications, similar to Adobe Inc., Adobe's Run time environment, runtime, Adobe Flash. A plugin for Silverlight is still available for a v ...
, and also various
HDTV High-definition television (HD or HDTV) describes a television system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since 1936; in more recent times, it refers to the g ...
broadcasts over terrestrial (
ATSC Advanced Television Systems Committee (ATSC) standards are an American set of standards for digital television transmission over terrestrial, cable and satellite networks. It is largely a replacement for the analog NTSC standard and, like that ...
,
ISDB-T Integrated Services Digital Broadcasting (ISDB; Japanese: , ''Tōgō dejitaru hōsō sābisu'') is a Japanese broadcasting standard for digital television (DTV) and digital radio. ISDB supersedes both the NTSC-J analog television system and th ...
,
DVB-T DVB-T, short for Digital Video Broadcasting – Terrestrial, is the DVB European-based consortium standard for the broadcast transmission of digital terrestrial television that was first published in 1997 and first broadcast in Singapore in Febr ...
or
DVB-T2 DVB-T2 is an abbreviation for "Digital Video Broadcasting – Second Generation Terrestrial"; it is the extension of the television standard DVB-T, issued by the consortium DVB, devised for the broadcast transmission of digital terrestrial telev ...
), cable (
DVB-C Digital Video Broadcasting - Cable (DVB-C) is the DVB European consortium standard for the broadcast transmission of digital television over cable. This system transmits an MPEG-2 or MPEG-4 family digital audio/digital video stream, using a QAM ...
), and satellite (
DVB-S Digital Video Broadcasting – Satellite (DVB-S) is the original DVB standard for Satellite Television and dates from 1995, in its first release, while development lasted from 1993 to 1997. The first commercial applications was by Star TV in Asia ...
and
DVB-S2 Digital Video Broadcasting - Satellite - Second Generation (DVB-S2) is a digital television broadcast standard that has been designed as a successor for the popular DVB-S system. It was developed in 2003 by the Digital Video Broadcasting Proje ...
) systems. H.264 is restricted by
patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention."A p ...
s owned by various parties. A license covering most (but not all) patents essential to H.264 is administered by a
patent pool In patent law, a patent pool is a consortium of at least two companies agreeing to cross-license patents relating to a particular technology. The creation of a patent pool can save patentees and licensees time and money, and, in case of blocking ...
administered by
MPEG LA MPEG LA is an American company based in Denver, Colorado that licenses patent pools covering essential patents required for use of the MPEG-2, MPEG-4, IEEE 1394, VC-1, ATSC, MVC, MPEG-2 Systems, AVC/H.264 and HEVC standards. History MPEG LA ...
. The commercial use of patented H.264 technologies requires the payment of royalties to MPEG LA and other patent owners. MPEG LA has allowed the free use of H.264 technologies for streaming Internet video that is free to end users, and
Cisco Systems Cisco Systems, Inc., commonly known as Cisco, is an American-based multinational corporation, multinational digital communications technology conglomerate (company), conglomerate corporation headquartered in San Jose, California. Cisco develo ...
pays royalties to MPEG LA on behalf of the users of binaries for its
open source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use the source code, design documents, or content of the product. The open-source model is a decentralized sof ...
H.264 encoder.


Naming

The H.264 name follows the
ITU-T The ITU Telecommunication Standardization Sector (ITU-T) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU). It is responsible for coordinating standards for telecommunications and Information Commu ...
naming convention A naming convention is a convention (generally agreed scheme) for naming things. Conventions differ in their intents, which may include to: * Allow useful information to be deduced from the names based on regularities. For instance, in Manhatta ...
, where Recommendations are given a letter corresponding to their series and a recommendation number within the series. H.264 is part of "H-Series Recommendations: Audiovisual and multimedia systems". H.264 is further categorized into "H.200-H.499: Infrastructure of audiovisual services" and "H.260-H.279: Coding of moving video". The MPEG-4 AVC name relates to the naming convention in
ISO ISO is the most common abbreviation for the International Organization for Standardization. ISO or Iso may also refer to: Business and finance * Iso (supermarket), a chain of Danish supermarkets incorporated into the SuperBest chain in 2007 * Iso ...
/
IEC The International Electrotechnical Commission (IEC; in French: ''Commission électrotechnique internationale'') is an international standards organization that prepares and publishes international standards for all electrical, electronic and r ...
MPEG The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by International Organization for Standardization, ISO and International Electrotechnical Commission, IEC that sets standards for media coding, includ ...
, where the standard is part 10 of ISO/IEC 14496, which is the suite of standards known as MPEG-4. The standard was developed jointly in a partnership of VCEG and MPEG, after earlier development work in the ITU-T as a VCEG project called H.26L. It is thus common to refer to the standard with names such as H.264/AVC, AVC/H.264, H.264/MPEG-4 AVC, or MPEG-4/H.264 AVC, to emphasize the common heritage. Occasionally, it is also referred to as "the JVT codec", in reference to the Joint Video Team (JVT) organization that developed it. (Such partnership and multiple naming is not uncommon. For example, the video compression standard known as MPEG-2 also arose from the partnership between
MPEG The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by International Organization for Standardization, ISO and International Electrotechnical Commission, IEC that sets standards for media coding, includ ...
and the ITU-T, where MPEG-2 video is known to the ITU-T community as H.262.) Some software programs (such as
VLC media player VLC media player (previously the VideoLAN Client and commonly known as simply VLC) is a free and open-source, portable, cross-platform media player software and streaming media server developed by the VideoLAN project. VLC is available for desk ...
) internally identify this standard as AVC1.


History


Overall history

In early 1998, the
Video Coding Experts Group The Video Coding Experts Group or Visual Coding Experts Group (VCEG, also known as Question 6) is a working group of the ITU Telecommunication Standardization Sector (ITU-T) concerned with standards for compression coding of video, images, audio, ...
(VCEG – ITU-T SG16 Q.6) issued a call for proposals on a project called H.26L, with the target to double the coding efficiency (which means halving the bit rate necessary for a given level of fidelity) in comparison to any other existing video coding standards for a broad variety of applications.
VCEG The Video Coding Experts Group or Visual Coding Experts Group (VCEG, also known as Question 6) is a working group of the ITU Telecommunication Standardization Sector (ITU-T) concerned with standards for compression coding of video, images, audio, ...
was chaired by Gary Sullivan (
Microsoft Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washing ...
, formerly
PictureTel PictureTel Corporation, often shortened to PictureTel Corp., was one of the first commercial videoconferencing product companies. It achieved peak revenues of over $490 million in 1996 and 1997 and was eventually acquired by Polycom in October ...
, U.S.). The first draft design for that new standard was adopted in August 1999. In 2000,
Thomas Wiegand Thomas Wiegand (born 6 May 1970 in Wismar) is a German electrical engineer who substantially contributed to the creation of the H.264/AVC, H.265/HEVC, and H.266/VVC video coding standards. For H.264/AVC, Wiegand was one of the chairmen of th ...
( Heinrich Hertz Institute, Germany) became VCEG co-chair. In December 2001, VCEG and the Moving Picture Experts Group (
MPEG The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by International Organization for Standardization, ISO and International Electrotechnical Commission, IEC that sets standards for media coding, includ ...
 –
ISO/IEC JTC 1/SC 29 ISO/IEC JTC 1/SC 29, entitled ''Coding of audio, picture, multimedia and hypermedia information'', is a standardization subcommittee of the Joint Technical Committee ISO/IEC JTC 1 of the International Organization for Standardization (ISO) and the I ...
/WG 11) formed a Joint Video Team (JVT), with the charter to finalize the video coding standard.Joint Video Team
ITU-T The ITU Telecommunication Standardization Sector (ITU-T) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU). It is responsible for coordinating standards for telecommunications and Information Commu ...
Web site.
Formal approval of the specification came in March 2003. The JVT was (is) chaired by Gary Sullivan,
Thomas Wiegand Thomas Wiegand (born 6 May 1970 in Wismar) is a German electrical engineer who substantially contributed to the creation of the H.264/AVC, H.265/HEVC, and H.266/VVC video coding standards. For H.264/AVC, Wiegand was one of the chairmen of th ...
, and Ajay Luthra (
Motorola Motorola, Inc. () was an American Multinational corporation, multinational telecommunications company based in Schaumburg, Illinois, United States. After having lost $4.3 billion from 2007 to 2009, the company split into two independent p ...
, U.S.: later
Arris In architecture, an arris is the sharp edge formed by the intersection of two surfaces, such as the corner of a masonry unit; the edge of a timber in timber framing; the junction between two planes of plaster or any intersection of divergent a ...
, U.S.). In July 2004, the Fidelity Range Extensions (FRExt) project was finalized. From January 2005 to November 2007, the JVT was working on an extension of H.264/AVC towards scalability by an Annex (G) called
Scalable Video Coding Scalable Video Coding: (SVC) is the name for the Annex G extension of the H.264/MPEG-4 AVC video compression standard. SVC standardizes the encoding of a high-quality video bitstream that also contains one or more subset bitstreams (a form of la ...
(SVC). The JVT management team was extended by Jens-Rainer Ohm (
RWTH Aachen University RWTH Aachen University (), also known as North Rhine-Westphalia Technical University of Aachen, Rhine-Westphalia Technical University of Aachen, Technical University of Aachen, University of Aachen, or ''Rheinisch-Westfälische Technische Hoch ...
, Germany). From July 2006 to November 2009, the JVT worked on
Multiview Video Coding Multi view Video Coding (MVC, also known as MVC 3D) is a stereoscopic video coding standard for video compression that allows for the efficient encoding of video sequences captured simultaneously from multiple camera angles in a single video str ...
(MVC), an extension of H.264/AVC towards
3D television 3D television (3DTV) is television that conveys depth perception to the viewer by employing techniques such as stereoscopic display, multi-view display, 2D-plus-depth, or any other form of 3D display. Most modern 3D television sets use an ...
and limited-range free-viewpoint television. That work included the development of two new profiles of the standard: the Multiview High Profile and the Stereo High Profile. Throughout the development of the standard, additional messages for containing supplemental enhancement information (SEI) have been developed. SEI messages can contain various types of data that indicate the timing of the video pictures or describe various properties of the coded video or how it can be used or enhanced. SEI messages are also defined that can contain arbitrary user-defined data. SEI messages do not affect the core decoding process, but can indicate how the video is recommended to be post-processed or displayed. Some other high-level properties of the video content are conveyed in video usability information (VUI), such as the indication of the
color space A color space is a specific organization of colors. In combination with color profiling supported by various physical devices, it supports reproducible representations of colorwhether such representation entails an analog or a digital represent ...
for interpretation of the video content. As new color spaces have been developed, such as for
high dynamic range High dynamic range (HDR) is a dynamic range higher than usual, synonyms are wide dynamic range, extended dynamic range, expanded dynamic range. The term is often used in discussing the dynamic range of various signals such as images, videos, au ...
and
wide color gamut In color reproduction, including computer graphics and photography, the gamut, or color gamut , is a certain ''complete subset'' of colors. The most common usage refers to the subset of colors which can be accurately represented in a given circ ...
video, additional VUI identifiers have been added to indicate them.


Fidelity range extensions and professional profiles

The standardization of the first version of H.264/AVC was completed in May 2003. In the first project to extend the original standard, the JVT then developed what was called the Fidelity Range Extensions (FRExt). These extensions enabled higher quality video coding by supporting increased sample bit depth precision and higher-resolution color information, including the sampling structures known as Y′CBCR 4:2:2 (a.k.a. YUV 4:2:2) and 4:4:4. Several other features were also included in the FRExt project, such as adding an 8×8 integer discrete cosine transform (integer DCT) with adaptive switching between the 4×4 and 8×8 transforms, encoder-specified perceptual-based quantization weighting matrices, efficient inter-picture lossless coding, and support of additional color spaces. The design work on the FRExt project was completed in July 2004, and the drafting work on them was completed in September 2004. Five other new profiles (see version 7 below) intended primarily for professional applications were then developed, adding extended-gamut color space support, defining additional aspect ratio indicators, defining two additional types of "supplemental enhancement information" (post-filter hint and tone mapping), and deprecating one of the prior FRExt profiles (the High 4:4:4 profile) that industry feedback indicated should have been designed differently.


Scalable video coding

The next major feature added to the standard was
Scalable Video Coding Scalable Video Coding: (SVC) is the name for the Annex G extension of the H.264/MPEG-4 AVC video compression standard. SVC standardizes the encoding of a high-quality video bitstream that also contains one or more subset bitstreams (a form of la ...
(SVC). Specified in Annex G of H.264/AVC, SVC allows the construction of bitstreams that contain ''layers'' of sub-bitstreams that also conform to the standard, including one such bitstream known as the "base layer" that can be decoded by a H.264/AVC
codec A codec is a device or computer program that encodes or decodes a data stream or signal. ''Codec'' is a portmanteau of coder/decoder. In electronic communications, an endec is a device that acts as both an encoder and a decoder on a signal or da ...
that does not support SVC. For temporal bitstream scalability (i.e., the presence of a sub-bitstream with a smaller temporal sampling rate than the main bitstream), complete access units are removed from the bitstream when deriving the sub-bitstream. In this case, high-level syntax and inter-prediction reference pictures in the bitstream are constructed accordingly. On the other hand, for spatial and quality bitstream scalability (i.e. the presence of a sub-bitstream with lower spatial resolution/quality than the main bitstream), the NAL (
Network Abstraction Layer The Network Abstraction Layer (NAL) is a part of the H.264/AVC and HEVC video coding standards. The main goal of the NAL is the provision of a "network-friendly" video representation addressing "conversational" (video telephony) and "non conversat ...
) is removed from the bitstream when deriving the sub-bitstream. In this case, inter-layer prediction (i.e., the prediction of the higher spatial resolution/quality signal from the data of the lower spatial resolution/quality signal) is typically used for efficient coding. The
Scalable Video Coding Scalable Video Coding: (SVC) is the name for the Annex G extension of the H.264/MPEG-4 AVC video compression standard. SVC standardizes the encoding of a high-quality video bitstream that also contains one or more subset bitstreams (a form of la ...
extensions were completed in November 2007.


Multiview video coding

The next major feature added to the standard was
Multiview Video Coding Multi view Video Coding (MVC, also known as MVC 3D) is a stereoscopic video coding standard for video compression that allows for the efficient encoding of video sequences captured simultaneously from multiple camera angles in a single video str ...
(MVC). Specified in Annex H of H.264/AVC, MVC enables the construction of bitstreams that represent more than one view of a video scene. An important example of this functionality is
stereoscopic 3D Stereoscopy (also called stereoscopics, or stereo imaging) is a technique for creating or enhancing the illusion of depth in an image by means of stereopsis for binocular vision. The word ''stereoscopy'' derives . Any stereoscopic image is ...
video coding. Two profiles were developed in the MVC work: Multiview High profile supports an arbitrary number of views, and Stereo High profile is designed specifically for two-view stereoscopic video. The Multiview Video Coding extensions were completed in November 2009.


3D-AVC and MFC stereoscopic coding

Additional extensions were later developed that included 3D video coding with joint coding of
depth map In 3D computer graphics and computer vision, a depth map is an image or image channel that contains information relating to the distance of the surfaces of scene objects from a viewpoint. The term is related (and may be analogous) to ''depth ...
s and texture (termed 3D-AVC), multi-resolution frame-compatible (MFC) stereoscopic and 3D-MFC coding, various additional combinations of features, and higher frame sizes and frame rates.


Versions

Versions of the H.264/AVC standard include the following completed revisions, corrigenda, and amendments (dates are final approval dates in ITU-T, while final "International Standard" approval dates in ISO/IEC are somewhat different and slightly later in most cases). Each version represents changes relative to the next lower version that is integrated into the text. * Version 1 (Edition 1): (May 30, 2003) First approved version of H.264/AVC containing Baseline, Main, and Extended profiles. * Version 2 (Edition 1.1): (May 7, 2004) Corrigendum containing various minor corrections. * Version 3 (Edition 2): (March 1, 2005) Major addition containing the first amendment, establishing the Fidelity Range Extensions (FRExt). This version added the High, High 10, High 4:2:2, and High 4:4:4 profiles. After a few years, the High profile became the most commonly used profile of the standard. * Version 4 (Edition 2.1): (September 13, 2005) Corrigendum containing various minor corrections and adding three aspect ratio indicators. * Version 5 (Edition 2.2): (June 13, 2006) Amendment consisting of removal of prior High 4:4:4 profile (processed as a corrigendum in ISO/IEC). * Version 6 (Edition 2.2): (June 13, 2006) Amendment consisting of minor extensions like extended-gamut color space support (bundled with above-mentioned aspect ratio indicators in ISO/IEC). * Version 7 (Edition 2.3): (April 6, 2007) Amendment containing the addition of the High 4:4:4 Predictive profile and four Intra-only profiles (High 10 Intra, High 4:2:2 Intra, High 4:4:4 Intra, and CAVLC 4:4:4 Intra). * Version 8 (Edition 3): (November 22, 2007) Major addition to H.264/AVC containing the amendment for
Scalable Video Coding Scalable Video Coding: (SVC) is the name for the Annex G extension of the H.264/MPEG-4 AVC video compression standard. SVC standardizes the encoding of a high-quality video bitstream that also contains one or more subset bitstreams (a form of la ...
(SVC) containing Scalable Baseline, Scalable High, and Scalable High Intra profiles. * Version 9 (Edition 3.1): (January 13, 2009) Corrigendum containing minor corrections. * Version 10 (Edition 4): (March 16, 2009) Amendment containing definition of a new profile (the Constrained Baseline profile) with only the common subset of capabilities supported in various previously specified profiles. * Version 11 (Edition 4): (March 16, 2009) Major addition to H.264/AVC containing the amendment for
Multiview Video Coding Multi view Video Coding (MVC, also known as MVC 3D) is a stereoscopic video coding standard for video compression that allows for the efficient encoding of video sequences captured simultaneously from multiple camera angles in a single video str ...
(MVC) extension, including the Multiview High profile. * Version 12 (Edition 5): (March 9, 2010) Amendment containing definition of a new MVC profile (the Stereo High profile) for two-view video coding with support of interlaced coding tools and specifying an additional supplemental enhancement information (SEI) message termed the frame packing arrangement SEI message. * Version 13 (Edition 5): (March 9, 2010) Corrigendum containing minor corrections. * Version 14 (Edition 6): (June 29, 2011) Amendment specifying a new level (Level 5.2) supporting higher processing rates in terms of maximum macroblocks per second, and a new profile (the Progressive High profile) supporting only the frame coding tools of the previously specified High profile. * Version 15 (Edition 6): (June 29, 2011) Corrigendum containing minor corrections. * Version 16 (Edition 7): (January 13, 2012) Amendment containing definition of three new profiles intended primarily for real-time communication applications: the Constrained High, Scalable Constrained Baseline, and Scalable Constrained High profiles. * Version 17 (Edition 8): (April 13, 2013) Amendment with additional SEI message indicators. * Version 18 (Edition 8): (April 13, 2013) Amendment to specify the coding of depth map data for 3D stereoscopic video, including a Multiview Depth High profile. * Version 19 (Edition 8): (April 13, 2013) Corrigendum to correct an error in the sub-bitstream extraction process for multiview video. * Version 20 (Edition 8): (April 13, 2013) Amendment to specify additional
color space A color space is a specific organization of colors. In combination with color profiling supported by various physical devices, it supports reproducible representations of colorwhether such representation entails an analog or a digital represent ...
identifiers (including support of ITU-R Recommendation BT.2020 for
UHDTV Ultra-high-definition television (also known as Ultra HD television, Ultra HD, UHDTV, UHD and Super Hi-Vision) today includes 4K UHD and 8K UHD, which are two digital video formats with an aspect ratio of 16:9. These were first proposed by ...
) and an additional model type in the tone mapping information SEI message. * Version 21 (Edition 9): (February 13, 2014) Amendment to specify the Enhanced Multiview Depth High profile. * Version 22 (Edition 9): (February 13, 2014) Amendment to specify the multi-resolution frame compatible (MFC) enhancement for 3D stereoscopic video, the MFC High profile, and minor corrections. * Version 23 (Edition 10): (February 13, 2016) Amendment to specify MFC stereoscopic video with depth maps, the MFC Depth High profile, the mastering display color volume SEI message, and additional color-related VUI codepoint identifiers. * Version 24 (Edition 11): (October 14, 2016) Amendment to specify additional levels of decoder capability supporting larger picture sizes (Levels 6, 6.1, and 6.2), the green metadata SEI message, the alternative depth information SEI message, and additional color-related VUI codepoint identifiers. * Version 25 (Edition 12): (April 13, 2017) Amendment to specify the Progressive High 10 profile,
hybrid log–gamma The hybrid log–gamma (HLG) transfer function is a transfer function jointly developed by the BBC and NHK for high dynamic range (HDR) display. It's backward compatible with the transfer function of SDR (the gamma curve). It was approved as ARIB S ...
(HLG), and additional color-related VUI code points and SEI messages. * Version 26 (Edition 13): (June 13, 2019) Amendment to specify additional SEI messages for ambient viewing environment, content light level information, content color volume, equirectangular projection, cubemap projection, sphere rotation, region-wise packing, omnidirectional viewport, SEI manifest, and SEI prefix. *Version 27 (Edition 14): (August 22, 2021) Amendment to specify additional SEI messages for annotated regions and shutter interval information, and miscellaneous minor corrections and clarifications.


Patent holders


Applications

The H.264 video format has a very broad application range that covers all forms of digital compressed video from low bit-rate Internet streaming applications to HDTV broadcast and Digital Cinema applications with nearly lossless coding. With the use of H.264, bit rate savings of 50% or more compared to
MPEG-2 Part 2 H.262 or MPEG-2 Part 2 (formally known as ITU-T Recommendation H.262 and ISO/IEC 13818-2, also known as MPEG-2 Video) is a video coding format standardised and jointly maintained by ITU-T Study Group 16 Video Coding Experts Group (VCEG) and ISO/ ...
are reported. For example, H.264 has been reported to give the same Digital Satellite TV quality as current MPEG-2 implementations with less than half the bitrate, with current MPEG-2 implementations working at around 3.5 Mbit/s and H.264 at only 1.5 Mbit/s. Sony claims that 9 Mbit/s AVC recording mode is equivalent to the image quality of the
HDV HDV is a format for recording of high-definition video on DV cassette tape. The format was originally developed by JVC and supported by Sony, Canon, and Sharp. The four companies formed the HDV Consortium in September 2003. Conceived as an af ...
format, which uses approximately 18–25 Mbit/s. To ensure compatibility and problem-free adoption of H.264/AVC, many standards bodies have amended or added to their video-related standards so that users of these standards can employ H.264/AVC. Both the
Blu-ray Disc The Blu-ray Disc (BD), often known simply as Blu-ray, is a Digital media, digital optical disc data storage format. It was invented and developed in 2005 and released on June 20, 2006 worldwide. It is designed to supersede the DVD format, and c ...
format and the now-discontinued
HD DVD HD DVD (short for High Definition Digital Versatile Disc) is an obsolete high-density optical disc format for storing data and playback of high-definition video. Supported principally by Toshiba, HD DVD was envisioned to be the successor to th ...
format include the H.264/AVC High Profile as one of three mandatory video compression formats. The Digital Video Broadcast project (
DVB Digital Video Broadcasting (DVB) is a set of international open standards for digital television. DVB standards are maintained by the DVB Project, an international industry consortium, and are published by a Joint Technical Committee (JTC) o ...
) approved the use of H.264/AVC for broadcast television in late 2004. The
Advanced Television Systems Committee The Advanced Television Systems Committee (ATSC) is an international nonprofit organization developing technical standards for digital terrestrial television and data broadcasting. ATSC's 120-plus member organizations represent the broadcast, br ...
(ATSC) standards body in the United States approved the use of H.264/AVC for broadcast television in July 2008, although the standard is not yet used for fixed ATSC broadcasts within the United States. It has also been approved for use with the more recent
ATSC-M/H ATSC-M/H (''Advanced Television Systems Committee - Mobile/Handheld'') is a U.S. standard for mobile digital TV that allows TV broadcasts to be received by mobile devices. ATSC-M/H is a mobile TV extension to preexisting terrestrial TV broadcasti ...
(Mobile/Handheld) standard, using the AVC and SVC portions of H.264. The
CCTV Closed-circuit television (CCTV), also known as video surveillance, is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors. It differs from broadcast television in that the signal is not openly t ...
(Closed Circuit TV) and
Video Surveillance Closed-circuit television (CCTV), also known as video surveillance, is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors. It differs from broadcast television in that the signal is not openly tr ...
markets have included the technology in many products. Many common
DSLR A digital single-lens reflex camera (digital SLR or DSLR) is a digital camera that combines the optics and the mechanisms of a single-lens reflex camera with a digital imaging sensor. The reflex design scheme is the primary difference between ...
s use H.264 video wrapped in QuickTime MOV containers as the native recording format.


Derived formats

AVCHD AVCHD (Advanced Video Coding High Definition) is a file-based format for the digital recording and playback of high-definition video. It is H.264 and Dolby AC-3 packaged into the MPEG transport stream, with a set of constraints designed around t ...
is a high-definition recording format designed by
Sony , commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professional ...
and
Panasonic formerly between 1935 and 2008 and the first incarnation of between 2008 and 2022, is a major Japanese multinational corporation, multinational Conglomerate (company), conglomerate corporation, headquartered in Kadoma, Osaka, Kadoma, Osaka P ...
that uses H.264 (conforming to H.264 while adding additional application-specific features and constraints).
AVC-Intra AVC-Intra is a type of video coding developed by Panasonic, and then supported in products made by other companies. AVC-Intra is available in Panasonic's high definition broadcast products, such as, for example, their P2 card equipped broadcast c ...
is an
intraframe Intra-frame coding is a data compression technique used within a video frame, enabling smaller file sizes and lower bitrates, with little or no loss in quality. Since neighboring pixels within an image are often very similar, rather than storing ...
-only compression format, developed by
Panasonic formerly between 1935 and 2008 and the first incarnation of between 2008 and 2022, is a major Japanese multinational corporation, multinational Conglomerate (company), conglomerate corporation, headquartered in Kadoma, Osaka, Kadoma, Osaka P ...
.
XAVC XAVC is a recording format that was introduced by Sony on October 30, 2012. XAVC is a format that will be licensed to companies that want to make XAVC products. Technical details XAVC uses level 5.2 of H.264/MPEG-4 AVC, which is the highest leve ...
is a recording format designed by Sony that uses level 5.2 of H.264/MPEG-4 AVC, which is the highest level supported by that video standard. XAVC can support
4K resolution 4K resolution refers to a horizontal display resolution of approximately 4,000 pixels. Digital television and digital cinematography commonly use several different 4K resolutions. In television and consumer media, 38402160 (4K Ultra-high-definitio ...
(4096 × 2160 and 3840 × 2160) at up to 60 
frames per second A frame is often a structural system that supports other components of a physical construction and/or steel frame that limits the construction's extent. Frame and FRAME may also refer to: Physical objects In building construction *Framing (con ...
(fps). Sony has announced that cameras that support XAVC include two
CineAlta CineAlta cameras are a series of professional digital movie cameras produced by Sony that replicate many of the same features of 35mm film motion picture cameras. Concept CineAlta is a brand name used by Sony to describe various products inv ...
cameras—the Sony PMW-F55 and Sony PMW-F5. The Sony PMW-F55 can record XAVC with 4K resolution at 30 fps at 300
Mbit/s In telecommunications, data-transfer rate is the average number of bits (bitrate), characters or symbols (baudrate), or data blocks per unit time passing through a communication link in a data-transmission system. Common data rate units are multi ...
and 2K resolution at 30 fps at 100 Mbit/s. XAVC can record 4K resolution at 60 fps with 4:2:2 chroma sampling at 600 Mbit/s.


Design


Features

H.264/AVC/MPEG-4 Part 10 contains a number of new features that allow it to compress video much more efficiently than older standards and to provide more flexibility for application to a wide variety of network environments. In particular, some such key features include: * Multi-picture inter-picture prediction including the following features: ** Using previously encoded pictures as references in a much more flexible way than in past standards, allowing up to 16 reference frames (or 32 reference fields, in the case of interlaced encoding) to be used in some cases. In profiles that support non- IDR frames, most levels specify that sufficient buffering should be available to allow for at least 4 or 5 reference frames at maximum resolution. This is in contrast to prior standards, where the limit was typically one; or, in the case of conventional " B pictures" (B-frames), two. ** Variable block-size
motion compensation Motion compensation in computing, is an algorithmic technique used to predict a frame in a video, given the previous and/or future frames by accounting for motion of the camera and/or objects in the video. It is employed in the encoding of video d ...
(VBSMC) with block sizes as large as 16×16 and as small as 4×4, enabling precise segmentation of moving regions. The supported
luma Luma or LUMA may refer to: Arts * La Trobe University Museum of Art, Melbourne, Australia * LUMA Projection Arts Festival, an annual event featuring building-scale projection mapping and light installations in Binghamton, NY * LUMA Foundation, ...
prediction block sizes include 16×16, 16×8, 8×16, 8×8, 8×4, 4×8, and 4×4, many of which can be used together in a single macroblock. Chroma prediction block sizes are correspondingly smaller when
chroma subsampling Chroma subsampling is the practice of encoding images by implementing less resolution for chroma information than for luma information, taking advantage of the human visual system's lower acuity for color differences than for luminance. It is us ...
is used. ** The ability to use multiple motion vectors per macroblock (one or two per partition) with a maximum of 32 in the case of a B macroblock constructed of 16 4×4 partitions. The motion vectors for each 8×8 or larger partition region can point to different reference pictures. ** The ability to use any macroblock type in
B-frames In the field of video compression a video frame is compressed using different algorithms with different advantages and disadvantages, centered mainly around amount of data compression. These different algorithms for video frames are called pictu ...
, including I-macroblocks, resulting in much more efficient encoding when using B-frames. This feature was notably left out from
MPEG-4 ASP MPEG-4 Part 2, MPEG-4 Visual (formally ISO/ IEC 14496-2) is a video compression format developed by the Moving Picture Experts Group (MPEG). It belongs to the MPEG-4 ISO/IEC standards. It uses block-wise motion compensation and a discrete cosine ...
. ** Six-tap filtering for derivation of half-pel luma sample predictions, for sharper subpixel motion-compensation. Quarter-pixel motion is derived by linear interpolation of the halfpixel values, to save processing power. ** Quarter-pixel precision for motion compensation, enabling precise description of the displacements of moving areas. For chroma the resolution is typically halved both vertically and horizontally (see 4:2:0) therefore the motion compensation of chroma uses one-eighth chroma pixel grid units. ** Weighted prediction, allowing an encoder to specify the use of a scaling and offset when performing motion compensation, and providing a significant benefit in performance in special cases—such as fade-to-black, fade-in, and cross-fade transitions. This includes implicit weighted prediction for B-frames, and explicit weighted prediction for P-frames. * Spatial prediction from the edges of neighboring blocks for "intra" coding, rather than the "DC"-only prediction found in MPEG-2 Part 2 and the transform coefficient prediction found in H.263v2 and MPEG-4 Part 2. This includes luma prediction block sizes of 16×16, 8×8, and 4×4 (of which only one type can be used within each
macroblock The macroblock is a processing unit in image and video compression formats based on linear block transforms, typically the discrete cosine transform (DCT). A macroblock typically consists of 16×16 samples, and is further subdivided into transform ...
). * Integer discrete cosine transform (integer DCT), a type of discrete cosine transform (DCT) where the transform is an integer approximation of the standard DCT. It has selectable block sizes and exact-match integer computation to reduce complexity, including: ** An exact-match integer 4×4 spatial block transform, allowing precise placement of residual signals with little of the "
ringing Ringing may mean: Vibrations * Ringing (signal), unwanted oscillation of a signal, leading to ringing artifacts * Vibration of a harmonic oscillator ** Bell ringing * Ringing (telephony), the sound of a telephone bell * Ringing (medicine), a ri ...
" often found with prior codec designs. It is similar to the standard DCT used in previous standards, but uses a smaller block size and simple integer processing. Unlike the cosine-based formulas and tolerances expressed in earlier standards (such as H.261 and MPEG-2), integer processing provides an exactly specified decoded result. ** An exact-match integer 8×8 spatial block transform, allowing highly correlated regions to be compressed more efficiently than with the 4×4 transform. This design is based on the standard DCT, but simplified and made to provide exactly specified decoding. ** Adaptive encoder selection between the 4×4 and 8×8 transform block sizes for the integer transform operation. ** A secondary
Hadamard transform The Hadamard transform (also known as the Walsh–Hadamard transform, Hadamard–Rademacher–Walsh transform, Walsh transform, or Walsh–Fourier transform) is an example of a generalized class of Fourier transforms. It performs an orthogonal ...
performed on "DC" coefficients of the primary spatial transform applied to chroma DC coefficients (and also luma in one special case) to obtain even more compression in smooth regions. *
Lossless Lossless compression is a class of data compression that allows the original data to be perfectly reconstructed from the compressed data with no loss of information. Lossless compression is possible because most real-world data exhibits statistic ...
macroblock coding features including: ** A lossless "PCM macroblock" representation mode in which video data samples are represented directly, allowing perfect representation of specific regions and allowing a strict limit to be placed on the quantity of coded data for each macroblock. ** An enhanced lossless macroblock representation mode allowing perfect representation of specific regions while ordinarily using substantially fewer bits than the PCM mode. * Flexible interlaced-scan video coding features, including: ** Macroblock-adaptive frame-field (MBAFF) coding, using a macroblock pair structure for pictures coded as frames, allowing 16×16 macroblocks in field mode (compared with MPEG-2, where field mode processing in a picture that is coded as a frame results in the processing of 16×8 half-macroblocks). ** Picture-adaptive frame-field coding (PAFF or PicAFF) allowing a freely selected mixture of pictures coded either as complete frames where both fields are combined for encoding or as individual single fields. * A quantization design including: ** Logarithmic step size control for easier bit rate management by encoders and simplified inverse-quantization scaling ** Frequency-customized quantization scaling matrices selected by the encoder for perceptual-based quantization optimization * An in-loop
deblocking filter A deblocking filter is a video filter applied to decoded compressed video to improve visual quality and prediction performance by smoothing the sharp edges which can form between macroblocks when block coding techniques are used. The filter aims ...
that helps prevent the blocking artifacts common to other DCT-based image compression techniques, resulting in better visual appearance and compression efficiency * An
entropy coding In information theory, an entropy coding (or entropy encoding) is any lossless data compression method that attempts to approach the lower bound declared by Shannon's source coding theorem, which states that any lossless data compression method ...
design including: **
Context-adaptive binary arithmetic coding Context-adaptive binary arithmetic coding (CABAC) is a form of entropy encoding used in the H.264/MPEG-4 AVC and High Efficiency Video Coding (HEVC) standards. It is a lossless compression technique, although the video coding standards in which it ...
(CABAC), an algorithm to losslessly compress syntax elements in the video stream knowing the probabilities of syntax elements in a given context. CABAC compresses data more efficiently than CAVLC but requires considerably more processing to decode. **
Context-adaptive variable-length coding Context-adaptive variable-length coding (CAVLC) is a form of entropy coding used in H.264/MPEG-4 AVC video encoding. It is an inherently lossless compression technique, like almost all entropy-coders. In H.264/MPEG-4 AVC, it is used to encode re ...
(CAVLC), which is a lower-complexity alternative to CABAC for the coding of quantized transform coefficient values. Although lower complexity than CABAC, CAVLC is more elaborate and more efficient than the methods typically used to code coefficients in other prior designs. ** A common simple and highly structured variable length coding (VLC) technique for many of the syntax elements not coded by CABAC or CAVLC, referred to as
Exponential-Golomb coding An exponential-Golomb code (or just Exp-Golomb code) is a type of universal code. To encode any nonnegative integer ''x'' using the exp-Golomb code: # Write down ''x''+1 in binary # Count the bits written, subtract one, and write that number of ...
(or Exp-Golomb). * Loss resilience features including: ** A
Network Abstraction Layer The Network Abstraction Layer (NAL) is a part of the H.264/AVC and HEVC video coding standards. The main goal of the NAL is the provision of a "network-friendly" video representation addressing "conversational" (video telephony) and "non conversat ...
(NAL) definition allowing the same video syntax to be used in many network environments. One very fundamental design concept of H.264 is to generate self-contained packets, to remove the header duplication as in MPEG-4's Header Extension Code (HEC). This was achieved by decoupling information relevant to more than one slice from the media stream. The combination of the higher-level parameters is called a parameter set. The H.264 specification includes two types of parameter sets: Sequence Parameter Set (SPS) and Picture Parameter Set (PPS). An active sequence parameter set remains unchanged throughout a coded video sequence, and an active picture parameter set remains unchanged within a coded picture. The sequence and picture parameter set structures contain information such as picture size, optional coding modes employed, and macroblock to slice group map.RFC 3984, p.3 ** Flexible macroblock ordering (FMO), also known as slice groups, and arbitrary slice ordering (ASO), which are techniques for restructuring the ordering of the representation of the fundamental regions (''macroblocks'') in pictures. Typically considered an error/loss robustness feature, FMO and ASO can also be used for other purposes. ** Data partitioning (DP), a feature providing the ability to separate more important and less important syntax elements into different packets of data, enabling the application of unequal error protection (UEP) and other types of improvement of error/loss robustness. ** Redundant slices (RS), an error/loss robustness feature that lets an encoder send an extra representation of a picture region (typically at lower fidelity) that can be used if the primary representation is corrupted or lost. ** Frame numbering, a feature that allows the creation of "sub-sequences", enabling temporal scalability by optional inclusion of extra pictures between other pictures, and the detection and concealment of losses of entire pictures, which can occur due to network packet losses or channel errors. * Switching slices, called SP and SI slices, allowing an encoder to direct a decoder to jump into an ongoing video stream for such purposes as video streaming bit rate switching and "trick mode" operation. When a decoder jumps into the middle of a video stream using the SP/SI feature, it can get an exact match to the decoded pictures at that location in the video stream despite using different pictures, or no pictures at all, as references prior to the switch. * A simple automatic process for preventing the accidental emulation of start codes, which are special sequences of bits in the coded data that allow random access into the bitstream and recovery of byte alignment in systems that can lose byte synchronization. * Supplemental enhancement information (SEI) and video usability information (VUI), which are extra information that can be inserted into the bitstream for various purposes such as indicating the color space used the video content or various constraints that apply to the encoding. SEI messages can contain arbitrary user-defined metadata payloads or other messages with syntax and semantics defined in the standard. * Auxiliary pictures, which can be used for such purposes as
alpha compositing In computer graphics, alpha compositing or alpha blending is the process of combining one image with a background to create the appearance of partial or full transparency. It is often useful to render picture elements (pixels) in separate pas ...
. * Support of monochrome (4:0:0), 4:2:0, 4:2:2, and 4:4:4
chroma sampling Chroma subsampling is the practice of encoding images by implementing less resolution for chroma information than for luma information, taking advantage of the human visual system's lower acuity for color differences than for luminance. It is us ...
(depending on the selected profile). * Support of sample bit depth precision ranging from 8 to 14 bits per sample (depending on the selected profile). * The ability to encode individual color planes as distinct pictures with their own slice structures, macroblock modes, motion vectors, etc., allowing encoders to be designed with a simple parallelization structure (supported only in the three 4:4:4-capable profiles). * Picture order count, a feature that serves to keep the ordering of the pictures and the values of samples in the decoded pictures isolated from timing information, allowing timing information to be carried and controlled/changed separately by a system without affecting decoded picture content. These techniques, along with several others, help H.264 to perform significantly better than any prior standard under a wide variety of circumstances in a wide variety of application environments. H.264 can often perform radically better than MPEG-2 video—typically obtaining the same quality at half of the bit rate or less, especially on high bit rate and high resolution video content. Like other ISO/IEC MPEG video standards, H.264/AVC has a reference software implementation that can be freely downloaded. Its main purpose is to give examples of H.264/AVC features, rather than being a useful application ''per se''. Some reference hardware design work has also been conducted in the
Moving Picture Experts Group The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by ISO and IEC that sets standards for media coding, including compression coding of audio, video, graphics, and genomic data; and transmission and f ...
. The above-mentioned aspects include features in all profiles of H.264. A profile for a codec is a set of features of that codec identified to meet a certain set of specifications of intended applications. This means that many of the features listed are not supported in some profiles. Various profiles of H.264/AVC are discussed in next section.


Profiles

The standard defines several sets of capabilities, which are referred to as ''profiles'', targeting specific classes of applications. These are declared using a profile code (profile_idc) and sometimes a set of additional constraints applied in the encoder. The profile code and indicated constraints allow a decoder to recognize the requirements for decoding that specific bitstream. (And in many system environments, only one or two profiles are allowed to be used, so decoders in those environments do not need to be concerned with recognizing the less commonly used profiles.) By far the most commonly used profile is the High Profile. Profiles for non-scalable 2D video applications include the following: ;Constrained Baseline Profile (CBP, 66 with constraint set 1): Primarily for low-cost applications, this profile is most typically used in videoconferencing and mobile applications. It corresponds to the subset of features that are in common between the Baseline, Main, and High Profiles. ;Baseline Profile (BP, 66): Primarily for low-cost applications that require additional data loss robustness, this profile is used in some videoconferencing and mobile applications. This profile includes all features that are supported in the Constrained Baseline Profile, plus three additional features that can be used for loss robustness (or for other purposes such as low-delay multi-point video stream compositing). The importance of this profile has faded somewhat since the definition of the Constrained Baseline Profile in 2009. All Constrained Baseline Profile bitstreams are also considered to be Baseline Profile bitstreams, as these two profiles share the same profile identifier code value. ;Extended Profile (XP, 88): Intended as the streaming video profile, this profile has relatively high compression capability and some extra tricks for robustness to data losses and server stream switching. ;Main Profile (MP, 77): This profile is used for standard-definition digital TV broadcasts that use the MPEG-4 format as defined in the DVB standard. It is not, however, used for high-definition television broadcasts, as the importance of this profile faded when the High Profile was developed in 2004 for that application. ;High Profile (HiP, 100): The primary profile for broadcast and disc storage applications, particularly for high-definition television applications (for example, this is the profile adopted by the
Blu-ray Disc The Blu-ray Disc (BD), often known simply as Blu-ray, is a Digital media, digital optical disc data storage format. It was invented and developed in 2005 and released on June 20, 2006 worldwide. It is designed to supersede the DVD format, and c ...
storage format and the
DVB Digital Video Broadcasting (DVB) is a set of international open standards for digital television. DVB standards are maintained by the DVB Project, an international industry consortium, and are published by a Joint Technical Committee (JTC) o ...
HDTV broadcast service). ;Progressive High Profile (PHiP, 100 with constraint set 4): Similar to the High profile, but without support of field coding features. ;Constrained High Profile (100 with constraint set 4 and 5): Similar to the Progressive High profile, but without support of B (bi-predictive) slices. ;High 10 Profile (Hi10P, 110): Going beyond typical mainstream consumer product capabilities, this profile builds on top of the High Profile, adding support for up to 10 bits per sample of decoded picture precision. ;High 422 Profile (Hi422P, 122): Primarily targeting professional applications that use interlaced video, this profile builds on top of the High 10 Profile, adding support for the 4:2:2
chroma sampling Chroma subsampling is the practice of encoding images by implementing less resolution for chroma information than for luma information, taking advantage of the human visual system's lower acuity for color differences than for luminance. It is us ...
format while using up to 10 bits per sample of decoded picture precision. ;High 444 Predictive Profile (Hi444PP, 244): This profile builds on top of the High 4:2:2 Profile, supporting up to 4:4:4 chroma sampling, up to 14 bits per sample, and additionally supporting efficient lossless region coding and the coding of each picture as three separate color planes. For camcorders, editing, and professional applications, the standard contains four additional
Intra-frame Intra-frame coding is a data compression technique used within a video frame, enabling smaller file sizes and lower bitrates, with little or no loss in quality. Since neighboring pixels within an image are often very similar, rather than storing ...
-only profiles, which are defined as simple subsets of other corresponding profiles. These are mostly for professional (e.g., camera and editing system) applications: ;High 10 Intra Profile (110 with constraint set 3): The High 10 Profile constrained to all-Intra use. ;High 422 Intra Profile (122 with constraint set 3): The High 4:2:2 Profile constrained to all-Intra use. ;High 444 Intra Profile (244 with constraint set 3): The High 4:4:4 Profile constrained to all-Intra use. ;CAVLC 444 Intra Profile (44): The High 4:4:4 Profile constrained to all-Intra use and to CAVLC entropy coding (i.e., not supporting CABAC). As a result of the
Scalable Video Coding Scalable Video Coding: (SVC) is the name for the Annex G extension of the H.264/MPEG-4 AVC video compression standard. SVC standardizes the encoding of a high-quality video bitstream that also contains one or more subset bitstreams (a form of la ...
(SVC) extension, the standard contains five additional ''scalable profiles'', which are defined as a combination of a H.264/AVC profile for the base layer (identified by the second word in the scalable profile name) and tools that achieve the scalable extension: ;Scalable Baseline Profile (83): Primarily targeting video conferencing, mobile, and surveillance applications, this profile builds on top of the Constrained Baseline profile to which the base layer (a subset of the bitstream) must conform. For the scalability tools, a subset of the available tools is enabled. ;Scalable Constrained Baseline Profile (83 with constraint set 5): A subset of the Scalable Baseline Profile intended primarily for real-time communication applications. ;Scalable High Profile (86): Primarily targeting broadcast and streaming applications, this profile builds on top of the H.264/AVC High Profile to which the base layer must conform. ;Scalable Constrained High Profile (86 with constraint set 5): A subset of the Scalable High Profile intended primarily for real-time communication applications. ;Scalable High Intra Profile (86 with constraint set 3): Primarily targeting production applications, this profile is the Scalable High Profile constrained to all-Intra use. As a result of the
Multiview Video Coding Multi view Video Coding (MVC, also known as MVC 3D) is a stereoscopic video coding standard for video compression that allows for the efficient encoding of video sequences captured simultaneously from multiple camera angles in a single video str ...
(MVC) extension, the standard contains two ''multiview profiles'': ;Stereo High Profile (128): This profile targets two-view
stereoscopic Stereoscopy (also called stereoscopics, or stereo imaging) is a technique for creating or enhancing the depth perception, illusion of depth in an image by means of stereopsis for binocular vision. The word ''stereoscopy'' derives . Any stere ...
3D video and combines the tools of the High profile with the inter-view prediction capabilities of the MVC extension. ;Multiview High Profile (118): This profile supports two or more views using both inter-picture (temporal) and MVC inter-view prediction, but does not support field pictures and macroblock-adaptive frame-field coding. The Multi-resolution Frame-Compatible (MFC) extension added two more profiles: ;MFC High Profile (134): A profile for stereoscopic coding with two-layer resolution enhancement. ;MFC Depth High Profile (135): The 3D-AVC extension added two more profiles: ;Multiview Depth High Profile (138): This profile supports joint coding of depth map and video texture information for improved compression of 3D video content. ;Enhanced Multiview Depth High Profile (139): An enhanced profile for combined multiview coding with depth information.


Feature support in particular profiles


Levels

As the term is used in the standard, a "''level''" is a specified set of constraints that indicate a degree of required decoder performance for a profile. For example, a level of support within a profile specifies the maximum picture resolution, frame rate, and bit rate that a decoder may use. A decoder that conforms to a given level must be able to decode all bitstreams encoded for that level and all lower levels. The maximum bit rate for the High Profile is 1.25 times that of the Constrained Baseline, Baseline, Extended and Main Profiles; 3 times for Hi10P, and 4 times for Hi422P/Hi444PP. The number of luma samples is 16×16=256 times the number of macroblocks (and the number of luma samples per second is 256 times the number of macroblocks per second).


Decoded picture buffering

Previously encoded pictures are used by H.264/AVC encoders to provide predictions of the values of samples in other pictures. This allows the encoder to make efficient decisions on the best way to encode a given picture. At the decoder, such pictures are stored in a virtual ''decoded picture buffer'' (DPB). The maximum capacity of the DPB, in units of frames (or pairs of fields), as shown in parentheses in the right column of the table above, can be computed as follows: : Where is a constant value provided in the table below as a function of level number, and and are the picture width and frame height for the coded video data, expressed in units of macroblocks (rounded up to integer values and accounting for cropping and macroblock pairing when applicable). This formula is specified in sections A.3.1.h and A.3.2.f of the 2017 edition of the standard.
For example, for an HDTV picture that is 1,920 samples wide () and 1,080 samples high (), a Level 4 decoder has a maximum DPB storage capacity of = 4 frames (or 8 fields). Thus, the value 4 is shown in parentheses in the table above in the right column of the row for Level 4 with the frame size 1920×1080. It is important to note that the current picture being decoded is ''not included'' in the computation of DPB fullness (unless the encoder has indicated for it to be stored for use as a reference for decoding other pictures or for delayed output timing). Thus, a decoder needs to actually have sufficient memory to handle (at least) one frame ''more'' than the maximum capacity of the DPB as calculated above.


Implementations

In 2009, the HTML5 working group was split between supporters of Ogg
Theora Theora is a free file format, free Lossy compression, lossy video compression format. It is developed by the Xiph.Org Foundation and distributed without licensing fees alongside their other free and open media projects, including the Vorbis ...
, a free video format which is thought to be unencumbered by patents, and H.264, which contains patented technology. As late as July 2009, Google and Apple were said to support H.264, while Mozilla and Opera support Ogg Theora (now Google, Mozilla and Opera all support Theora and
WebM WebM is an audiovisual media file format. It is primarily intended to offer a royalty-free alternative to use in the HTML5 video and the HTML5 audio elements. It has a sister project, WebP, for images. The development of the format is sponsored ...
with
VP8 VP8 is an open and royalty-free video compression format released by On2 Technologies in 2008. Initially released as a proprietary successor to On2's previous VP7 format, VP8 was released as an open and royalty-free format in May 2010 after Goog ...
). Microsoft, with the release of Internet Explorer 9, has added support for HTML 5 video encoded using H.264. At the Gartner Symposium/ITXpo in November 2010, Microsoft CEO Steve Ballmer answered the question "HTML 5 or
Silverlight Microsoft Silverlight is a discontinued application framework designed for writing and running rich web applications, similar to Adobe Inc., Adobe's Run time environment, runtime, Adobe Flash. A plugin for Silverlight is still available for a v ...
?" by saying "If you want to do something that is universal, there is no question the world is going HTML5." In January 2011, Google announced that they were pulling support for H.264 from their Chrome browser and supporting both Theora and
WebM WebM is an audiovisual media file format. It is primarily intended to offer a royalty-free alternative to use in the HTML5 video and the HTML5 audio elements. It has a sister project, WebP, for images. The development of the format is sponsored ...
/
VP8 VP8 is an open and royalty-free video compression format released by On2 Technologies in 2008. Initially released as a proprietary successor to On2's previous VP7 format, VP8 was released as an open and royalty-free format in May 2010 after Goog ...
to use only open formats. On March 18, 2012,
Mozilla Mozilla (stylized as moz://a) is a free software community founded in 1998 by members of Netscape. The Mozilla community uses, develops, spreads and supports Mozilla products, thereby promoting exclusively free software and open standards, wi ...
announced support for H.264 in Firefox on mobile devices, due to prevalence of H.264-encoded video and the increased power-efficiency of using dedicated H.264 decoder hardware common on such devices. On February 20, 2013, Mozilla implemented support in Firefox for decoding H.264 on Windows 7 and above. This feature relies on Windows' built in decoding libraries. Firefox 35.0, released on January 13, 2015, supports H.264 on OS X 10.6 and higher. On October 30, 2013,
Rowan Trollope Rowan Trollope (born 1972) is an American business executive and technology entrepreneur. He is the former CEO of Five9, a publicly traded cloud software company whom Zoom announced their intent to acquire in July 2021 The deal was terminated by ...
from
Cisco Systems Cisco Systems, Inc., commonly known as Cisco, is an American-based multinational corporation, multinational digital communications technology conglomerate (company), conglomerate corporation headquartered in San Jose, California. Cisco develo ...
announced that Cisco would release both binaries and source code of an H.264 video codec called
OpenH264 OpenH264 is a free software library for real-time encoding and decoding video streams in the H.264/MPEG-4 AVC format. It is released under the terms of the Simplified BSD License." History Move to free-to-use binaries On October 30, 2013, Rowan T ...
under the
Simplified BSD license BSD licenses are a family of permissive free software licenses, imposing minimal restrictions on the use and distribution of covered software. This is in contrast to copyleft licenses, which have share-alike requirements. The original BSD lic ...
, and pay all royalties for its use to MPEG LA for any software projects that use Cisco's precompiled binaries, thus making Cisco's OpenH264 ''binaries'' free to use. However, any software projects that use Cisco's source code instead of its binaries would be legally responsible for paying all royalties to MPEG LA. Target CPU architectures include x86 and ARM, and target operating systems include Linux, Windows XP and later, Mac OS X, and Android; iOS was notably absent from this list, because it doesn't allow applications to fetch and install binary modules from the Internet. Also on October 30, 2013,
Brendan Eich Brendan Eich (; born July 4, 1961) is an American computer programmer and technology executive. He created the JavaScript programming language and co-founded the Mozilla project, the Mozilla Foundation, and the Mozilla Corporation. He served as ...
from
Mozilla Mozilla (stylized as moz://a) is a free software community founded in 1998 by members of Netscape. The Mozilla community uses, develops, spreads and supports Mozilla products, thereby promoting exclusively free software and open standards, wi ...
wrote that it would use Cisco's binaries in future versions of Firefox to add support for H.264 to Firefox where platform codecs are not available. Cisco published the source code to OpenH264 on December 9, 2013. Although iOS was not supported by the 2013 Cisco software release, Apple updated its Video Toolbox Framework with
iOS 8 iOS 8 is the eighth major release of the iOS mobile operating system developed by Apple Inc., being the successor to iOS 7. It was announced at the company's Worldwide Developers Conference on June 2, 2014, and was released on September 17, 2 ...
(released in September 2014) to provide direct access to hardware-based H.264/AVC video encoding and decoding.


Software encoders


Hardware

Because H.264 encoding and decoding requires significant computing power in specific types of arithmetic operations, software implementations that run on general-purpose CPUs are typically less power efficient. However, the latest quad-core general-purpose x86 CPUs have sufficient computation power to perform real-time SD and HD encoding. Compression efficiency depends on video algorithmic implementations, not on whether hardware or software implementation is used. Therefore, the difference between hardware and software based implementation is more on power-efficiency, flexibility and cost. To improve the power efficiency and reduce hardware form-factor, special-purpose hardware may be employed, either for the complete encoding or decoding process, or for acceleration assistance within a CPU-controlled environment. CPU based solutions are known to be much more flexible, particularly when encoding must be done concurrently in multiple formats, multiple bit rates and resolutions (
multi-screen video In the fields of broadcasting and content delivery, multiscreen video describes video content that is transformed into multiple formats, bit rates and resolutions for display on devices such as televisions, mobile phones, tablets and computers. A ...
), and possibly with additional features on container format support, advanced integrated advertising features, etc. CPU based software solution generally makes it much easier to load balance multiple concurrent encoding sessions within the same CPU. The 2nd generation
Intel Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the developers of the x86 seri ...
"
Sandy Bridge Sandy Bridge is the codename for Intel's 32 nm microarchitecture used in the second generation of the Intel Core processors (Core i7, i5, i3). The Sandy Bridge microarchitecture is the successor to Nehalem and Westmere microarchitecture ...
" Core i3/i5/i7 processors introduced at the January 2011 CES (
Consumer Electronics Show CES (; formerly an initialism for Consumer Electronics Show) is an annual trade show organized by the Consumer Technology Association (CTA). Held in January at the Las Vegas Convention Center in Winchester, Nevada, United States, the event typi ...
) offer an on-chip hardware full HD H.264 encoder, known as
Intel Quick Sync Video Intel Quick Sync Video is Intel's brand for its dedicated video encoding and decoding hardware core. Quick Sync was introduced with the Sandy Bridge CPU microarchitecture on 9 January 2011 and has been found on the die of Intel CPUs ever since. ...
. A hardware H.264 encoder can be an
ASIC An application-specific integrated circuit (ASIC ) is an integrated circuit (IC) chip customized for a particular use, rather than intended for general-purpose use, such as a chip designed to run in a digital voice recorder or a high-efficien ...
or an
FPGA A field-programmable gate array (FPGA) is an integrated circuit designed to be configured by a customer or a designer after manufacturinghence the term '' field-programmable''. The FPGA configuration is generally specified using a hardware de ...
. ASIC encoders with H.264 encoder functionality are available from many different semiconductor companies, but the core design used in the ASIC is typically licensed from one of a few companies such as
Chips&Media Chips&Media, Inc. is a provider of intellectual property for integrated circuits (commonly called "chips") such as system on a chip technology for encoding and decoding video (video codecs), and image processing. Headquartered in Seoul, South Kor ...
, Allegro DVT,
On2 On2 Technologies, formerly known as The Duck Corporation, was a small publicly traded company (on the American Stock Exchange), founded in New York City in 1992 and headquartered in Clifton Park, New York, that designed video codec technology. It ...
(formerly Hantro, acquired by Google),
Imagination Technologies Imagination Technologies Limited is a British semiconductor and software design company owned by Canyon Bridge Capital Partners, a private equity fund based in Beijing that is ultimately owned by the Chinese government. With its global headquar ...
, NGCodec. Some companies have both FPGA and ASIC product offerings. Texas Instruments manufactures a line of ARM + DSP cores that perform DSP H.264 BP encoding 1080p at 30fps. This permits flexibility with respect to codecs (which are implemented as highly optimized DSP code) while being more efficient than software on a generic CPU.


Licensing

In countries where patents on software algorithms are upheld, vendors and commercial users of products that use H.264/AVC are expected to pay patent licensing royalties for the patented technology that their products use. This applies to the Baseline Profile as well. A private organization known as
MPEG LA MPEG LA is an American company based in Denver, Colorado that licenses patent pools covering essential patents required for use of the MPEG-2, MPEG-4, IEEE 1394, VC-1, ATSC, MVC, MPEG-2 Systems, AVC/H.264 and HEVC standards. History MPEG LA ...
, which is not affiliated in any way with the MPEG standardization organization, administers the licenses for patents applying to this standard, as well as other
patent pool In patent law, a patent pool is a consortium of at least two companies agreeing to cross-license patents relating to a particular technology. The creation of a patent pool can save patentees and licensees time and money, and, in case of blocking ...
s, such as for MPEG-4 Part 2 Video, HEVC and MPEG-DASH. The patent holders include
Fujitsu is a Japanese multinational information and communications technology equipment and services corporation, established in 1935 and headquartered in Tokyo. Fujitsu is the world's sixth-largest IT services provider by annual revenue, and the la ...
,
Panasonic formerly between 1935 and 2008 and the first incarnation of between 2008 and 2022, is a major Japanese multinational corporation, multinational Conglomerate (company), conglomerate corporation, headquartered in Kadoma, Osaka, Kadoma, Osaka P ...
,
Sony , commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professional ...
,
Mitsubishi The is a group of autonomous Japanese multinational companies in a variety of industries. Founded by Yatarō Iwasaki in 1870, the Mitsubishi Group historically descended from the Mitsubishi zaibatsu, a unified company which existed from 1870 ...
,
Apple An apple is an edible fruit produced by an apple tree (''Malus domestica''). Apple fruit tree, trees are agriculture, cultivated worldwide and are the most widely grown species in the genus ''Malus''. The tree originated in Central Asia, wh ...
,
Columbia University Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhatt ...
,
KAIST The Korea Advanced Institute of Science and Technology (KAIST) is a national research university located in Daedeok Innopolis, Daejeon, South Korea. KAIST was established by the Korean government in 1971 as the nation's first public, research ...
,
Dolby Dolby Laboratories, Inc. (often shortened to Dolby Labs and known simply as Dolby) is an American company specializing in audio noise reduction, audio encoding/compression, spatial audio, and HDR imaging. Dolby licenses its technologies to ...
,
Google Google LLC () is an American multinational technology company focusing on search engine technology, online advertising, cloud computing, computer software, quantum computing, e-commerce, artificial intelligence, and consumer electronics. ...
,
JVC Kenwood , stylized as JVCKENWOOD, is a Japanese multinational electronics company headquartered in Yokohama, Japan. It was formed from the merger of Victor Company of Japan, Ltd (JVC) and Kenwood Corporation on October 1, 2008. Upon creation, Haruo Kaw ...
,
LG Electronics LG Electronics Inc. () is a South Korean multinational electronics company headquartered in Yeouido-dong, Seoul, South Korea. LG Electronics is a part of LG Corporation, the fourth largest '' chaebol'' in South Korea, and often considered a ...
,
Microsoft Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washing ...
, NTT Docomo,
Philips Koninklijke Philips N.V. (), commonly shortened to Philips, is a Dutch multinational conglomerate corporation that was founded in Eindhoven in 1891. Since 1997, it has been mostly headquartered in Amsterdam, though the Benelux headquarters i ...
,
Samsung The Samsung Group (or simply Samsung) ( ko, 삼성 ) is a South Korean multinational manufacturing conglomerate headquartered in Samsung Town, Seoul, South Korea. It comprises numerous affiliated businesses, most of them united under the ...
,
Sharp Sharp or SHARP may refer to: Acronyms * SHARP (helmet ratings) (Safety Helmet Assessment and Rating Programme), a British motorcycle helmet safety rating scheme * Self Help Addiction Recovery Program, a charitable organisation founded in 199 ...
,
Toshiba , commonly known as Toshiba and stylized as TOSHIBA, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. Its diversified products and services include power, industrial and social infrastructure system ...
and
ZTE ZTE Corporation is a Chinese partially state-owned technology company that specializes in telecommunication. Founded in 1985, ZTE is listed on both the Hong Kong and Shenzhen Stock Exchanges. ZTE's core business is wireless, exchange, optic ...
, although the majority of patents in the pool are held by
Panasonic formerly between 1935 and 2008 and the first incarnation of between 2008 and 2022, is a major Japanese multinational corporation, multinational Conglomerate (company), conglomerate corporation, headquartered in Kadoma, Osaka, Kadoma, Osaka P ...
( patents), Godo Kaisha IP Bridge ( patents) and
LG Electronics LG Electronics Inc. () is a South Korean multinational electronics company headquartered in Yeouido-dong, Seoul, South Korea. LG Electronics is a part of LG Corporation, the fourth largest '' chaebol'' in South Korea, and often considered a ...
( patents). On August 26, 2010, MPEG LA announced that royalties won't be charged for H.264 encoded Internet video that is free to end users. All other royalties remain in place, such as royalties for products that decode and encode H.264 video as well as to operators of free television and subscription channels. The license terms are updated in 5-year blocks. Since the first version of the standard was completed in May 2003 ( years ago) and the most commonly used profile (the High profile) was completed in June 2004 ( years ago), a number of the relevant patents that apply to the standard expires every year, although one of the US patents in the MPEG LA H.264 pool lasts at least until November 2030. with an earliest priority date of September 14, 2001 has a 2,998 day term extension. In 2005, Qualcomm sued Broadcom in US District Court, alleging that Broadcom infringed on two of its patents by making products that were compliant with the H.264 video compression standard.Se
Qualcomm Inc. v. Broadcom Corp.
No. 2007-1545, 2008-1162 (Fed. Cir. December 1, 2008). For articles in the popular press, see signonsandiego.com

an

and bloomberg.co
"Broadcom Wins First Trial in Qualcomm Patent Dispute"
/ref> In 2007, the District Court found that the patents were unenforceable because Qualcomm had failed to disclose them to the JVT prior to the release of the H.264 standard in May 2003. In December 2008, the US Court of Appeals for the Federal Circuit affirmed the District Court's order that the patents be unenforceable but remanded to the District Court with instructions to limit the scope of unenforceability to H.264 compliant products.


See also

*
VC-1 SMPTE 421, informally known as VC-1, is a video coding format. Most of it was initially developed as Microsoft's proprietary video format Windows Media Video 9 in 2003. With some enhancements including the development of a new Advanced Profile, ...
, a standard designed by
Microsoft Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washing ...
and approved as a
SMPTE The Society of Motion Picture and Television Engineers (SMPTE) (, rarely ), founded in 1916 as the Society of Motion Picture Engineers or SMPE, is a global professional association of engineers, technologists, and executives working in the m ...
standard in 2006 **
Comparison of H.264 and VC-1 H.264 and VC-1 SMPTE 421, informally known as VC-1, is a video coding format. Most of it was initially developed as Microsoft's proprietary video format Windows Media Video 9 in 2003. With some enhancements including the development of a new ...
*
Dirac (video compression format) Dirac is an open and royalty-free video compression format, specification and system developed by BBC Research & Development. Schrödinger and dirac-research (formerly just called "Dirac") are open and royalty-free software implementations (vi ...
, a video coding design by
BBC Research & Development BBC Research & Development is the technical research department of the BBC. Function It has responsibility for researching and developing advanced and emerging media technologies for the benefit of the corporation, and wider UK and European m ...
, released in 2008 *
VP8 VP8 is an open and royalty-free video compression format released by On2 Technologies in 2008. Initially released as a proprietary successor to On2's previous VP7 format, VP8 was released as an open and royalty-free format in May 2010 after Goog ...
, a video coding design by
On2 Technologies On2 Technologies, formerly known as The Duck Corporation, was a small publicly traded company (on the American Stock Exchange), founded in New York City in 1992 and headquartered in Clifton Park, New York, that designed video codec technology. It ...
(later purchased by
Google Google LLC () is an American multinational technology company focusing on search engine technology, online advertising, cloud computing, computer software, quantum computing, e-commerce, artificial intelligence, and consumer electronics. ...
), released in 2008 *
VP9 VP9 is an open and royalty-free video coding format developed by Google. VP9 is the successor to VP8 and competes mainly with MPEG's High Efficiency Video Coding (HEVC/H.265). At first, VP9 was mainly used on Google's video platform YouTube. ...
, a video coding design by
Google Google LLC () is an American multinational technology company focusing on search engine technology, online advertising, cloud computing, computer software, quantum computing, e-commerce, artificial intelligence, and consumer electronics. ...
, released in 2013 *
High Efficiency Video Coding High Efficiency Video Coding (HEVC), also known as H.265 and MPEG-H Part 2, is a video compression standard designed as part of the MPEG-H project as a successor to the widely used Advanced Video Coding (AVC, H.264, or MPEG-4 Part 10). In compar ...
(ITU-T H.265 or ISO/IEC 23008-2), an ITU/ISO/IEC standard, released in 2013 *
AV1 AOMedia Video 1 (AV1) is an open, royalty-free video coding format initially designed for video transmissions over the Internet. It was developed as a successor to VP9 by the Alliance for Open Media (AOMedia), a consortium founded in 2015 that ...
, a video coding design by the
Alliance for Open Media The Alliance for Open Media (AOMedia) is a non-profit industry consortium that develops open, royalty-free technology for multimedia delivery headquartered in Wakefield, Massachusetts. It uses the ideas and principles of open web standard develop ...
, released in 2018 *
Versatile Video Coding Versatile Video Coding (VVC), also known as H.266, ISO/IEC 23090-3, and MPEG-I Part 3, is a Video coding format, video compression standard finalized on 6 July 2020, by the Joint Video Experts Team (JVET), a joint video expert team of the Video ...
(ITU-T H.266 or ISO/IEC 23091-3), an ITU/ISO/IEC standard, released in 2020 *
Internet Protocol television Internet Protocol television (IPTV) is the delivery of television content over Internet Protocol (IP) networks. This is in contrast to delivery through traditional terrestrial, satellite, and cable television formats. Unlike downloaded media, ...
*
Group of pictures In video coding, a group of pictures, or GOP structure, specifies the order in which intra- and inter-frames are arranged. The GOP is a collection of successive pictures within a coded video stream. Each coded video stream consists of successive ...
*
Intra-frame coding Intra-frame coding is a data compression technique used within a video frame, enabling smaller file sizes and lower bitrates, with little or no loss in quality. Since neighboring pixels within an image are often very similar, rather than storing ...
*
Inter frame An inter frame is a frame in a video compression stream which is expressed in terms of one or more neighboring frames. The "inter" part of the term refers to the use of ''Inter frame prediction''. This kind of prediction tries to take advantage fro ...


References


Further reading

* * * * * *


External links

*
MPEG-4 AVC/H.264 Information
Doom9's Forum

* * * * * * (dated December 2007) * (dated April 2009) * (dated May 2010) {{DEFAULTSORT:H.264 MPEG-4 AVC High-definition television Open standards covered by patents Video codecs Video compression Videotelephony ITU-T recommendations
H.264 Advanced Video Coding (AVC), also referred to as H.264 or MPEG-4 Part 10, is a video compression standard based on block-oriented, motion-compensated coding. It is by far the most commonly used format for the recording, compression, and distri ...
H.26x ISO standards
MPEG-4 Part 10 Advanced Video Coding (AVC), also referred to as H.264 or MPEG-4 Part 10, is a video compression standard based on block-oriented, motion-compensated coding. It is by far the most commonly used format for the recording, compression, and distr ...
IEC standards