Video file format

A video file format is a type of file format for storing digital video data on a computer system. Video is almost always stored using lossy compression to reduce the file size.

A video file normally consists of a container (e.g. in the Matroska format) containing visual (video without audio) data in a video coding format (e.g. VP9) alongside audio data in an audio coding format (e.g. Opus). The container can also contain synchronization information, subtitles, and metadata such as title. A standardized (or in some cases de facto standard) video file type such as .webm is a profile specified by a restriction on which container format and which video and audio compression formats are allowed.

The coded video and audio inside a video file container (i.e. not headers, footers, and metadata) is called the essence. A program (or hardware) which can decode compressed video or audio is called a codec; playing or encoding a video file will sometimes require the user to install a codec library corresponding to the type of video and audio coding used in the file.

Good design normally dictates that a file extension enables the user to derive which program will open the file from the file extension. That is the case with some video file formats, such as WebM (.webm), Windows Media Video (.wmv), Flash Video (.flv), and Ogg Video (.ogv), each of which can only contain a few well-defined subtypes of video and audio coding formats, making it relatively easy to know which codec will play the file. In contrast to that, some very general-purpose container types like AVI (.avi) and QuickTime (.mov) can contain video and audio in almost any format, and have file extensions named after the container type, making it very hard for the end user to use the file extension to derive which codec or program to use to play the files.

The free software FFmpeg project's libraries have very wide support for encoding and decoding video file formats. For example, Google uses ffmpeg to support a wide range of upload video formats for YouTube.[1] One widely used media player using the ffmpeg libraries is the free software VLC media player, which can play most video files that end users will encounter.

List of video file formats
Name File extension(s) Container format Video coding format(s) Audio coding format(s) Notes
WebM .webm Matroska VP8, VP9, AV1 Vorbis, Opus Royalty-free format created for HTML5 video.
Matroska .mkv Matroska any any
Flash Video (FLV) .flv FLV VP6, Sorenson Spark, Screen video, Screen video 2, H.264 MP3, ADPCM, Nellymoser, Speex, AAC Use of the H.264 and AAC compression formats in the FLV file format has some limitations and authors of Flash Player strongly encourage everyone to embrace the new standard F4V file format[2] de facto standard for web-based streaming video (over RTMP).
F4V .flv MPEG-4 Part 12 H.264 MP3, AAC Replacement for FLV.
Vob .vob VOB H.262/MPEG-2 Part 2 or MPEG-1 Part 2 PCM, DTS, MPEG-1, Audio Layer II (MP2), or Dolby Digital (AC-3) Files in VOB format have .vob filename extension and are typically stored in the VIDEO_TS folder at the root of a DVD. The VOB format is based on the MPEG program stream format.
Ogg Video .ogv, .ogg Ogg Theora, Dirac Vorbis, FLAC
Dirac .drc  ? Dirac  ?
GIF .gif N/A N/A none Simple animation, inefficient compression, no sound, widely supported
Video alternative to GIF .gifv HTML any none Not standardized, and not a real video file in the classical meaning since it merely references the real video file (e.g. a .webm file), which has to exist separately elsewhere. A .gifv "file" is simply a HTML webpage which includes a HTML5 video tag, where the video has no sound. As there were large communities online which create art using the medium of short soundless videos in GIF format, GIFV was created as a functionally similar replacement with vastly smaller filesizes than the inefficient GIF format.
Multiple-image Network Graphics .mng N/A N/A none Inefficient, not widely used.
AVI .avi AVI any any Uses RIFF
MPEG Transport Stream .MTS, .M2TS, .TS AVCHD AVCHD (MPEG-4 / H.264 ) Dolby AC-3 or uncompressed linear PCM The standard video format used by many Sony and Panasonic HD camcorders. It is also used for storing high definition video on Blu-ray discs.
QuickTime File Format .mov, .qt QuickTime many[3] AAC, MP3, others[3]
Windows Media Video .wmv ASF Windows Media Video, Windows Media Video Screen, Windows Media Video Image Windows Media Audio, Sipro ACELP.net
Raw video format .yuv Further documentation needed Doesn't apply Doesn't apply Supports all resolutions, sampling structures, and frame rates
RealMedia (RM) .rm RealMedia RealVideo RealAudio Made for RealPlayer
RealMedia Variable Bitrate (RMVB) .rmvb RealMedia Variable Bitrate RealVideo RealAudio Made for RealPlayer
VivoActive (VIV) .viv VIV based upon H.263 video G.723 ADPCM audio (not the G.723.1 speech codec) Made for VivoActive Player
Advanced Systems Format (ASF) .asf ASF any any
AMV video format .amv Modified version of AVI[4] Variant of Motion JPEG Variant of IMA, ADPCM Proprietary video file format produced for MP4 players and S1 MP3 players with video playback
MPEG-4 Part 14 (MP4) .mp4, .m4p (with DRM), .m4v MPEG-4 Part 12 H.264, H.265, MPEG-4 Part 2, MPEG-2, MPEG-1 Advanced Audio Coding, MP3, others
MPEG-1 .mpg, .mp2, .mpeg, .mpe, .mpv MPEG-1 part 1 MPEG-1 part 2 MPEG-1 Audio Layer I, MPEG-1 Audio Layer III (MP3) Old, but very widely used due to installed base.
MPEG-2 – Video .mpg, .mpeg, .m2v  ? H.262 AAC, MP3, MPEG-2 Part 3, others
M4V .m4v MPEG-4 Part 12 H.264 AAC, Dolby Digital Developed by Apple, used in iTunes. Very similar to MP4 format, but may optionally have DRM.
SVI .svi MPEG-4 utilising a special header  ?  ? Samsung video format for portable players
3GPP .3gp MPEG-4 Part 12 MPEG-4 Part 2, H.263, H.264 AMR-NB, AMR-WB, AMR-WB+, AAC-LC, HE-AAC v1 or Enhanced aacPlus (HE-AAC v2) Common video format for cell phones
3GPP2 .3g2 MPEG-4 Part 12 MPEG-4 Part 2, H.263, H.264 AMR-NB, AMR-WB, AMR-WB+, AAC-LC, HE-AAC v1 or Enhanced aacPlus (HE-AAC v2), EVRC, SMV or VMR-WB Common video format for cell phones
Material Exchange Format (MXF) .mxf MXF  ?  ?
ROQ .roq  ?  ?  ? used by Quake 3[5]
Nullsoft Streaming Video (NSV) .nsv NSV  ? ? For streaming video content over the Internet
Flash Video (FLV) .flv .f4v .f4p .f4a .f4b Audio, video, text, data Adobe Flash Platform SWF, F4V, ISO base media file format Developed by the Adobe Flash Platform

See also

References
  1. "Google's YouTube Uses FFmpeg | Breaking Eggs And Making Omelettes". multimedia.cx. 9 February 2011.
  2. Kaourantin.net (31 October 2007) Tinic Uro New File Extensions and MIME Types Archived 2010-07-06 at the Wayback Machine, Retrieved on 2009-08-03
  3. "QuickTime File Format". www.digitalpreservation.gov. 2013-02-14.
  4. "AMV codec tools" code.google.com
  5. "RoQ - MultimediaWiki". wiki.multimedia.cx.
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