VideoLAN Wiki - User contributions [en]

VP8

2010-07-14T14:39:11Z

DB-tester: wow

{{codec video|id=vp8|mod=ffmpeg}}
'''VP8''' is a video codec created by [[On2]] and used in Webm files.

== Compatibility ==

???

== Examples ==

http://camendesign.com/code/video_for_everybody

Lossless and lossy

2009-10-30T07:56:17Z

DB-tester: fix

'''Lossless''' is a way of compressing data which is fully reversible -- e.g., does not "throw away" data. A losslessly compressed file can be used to create an exact copy of the source file.

'''Lossy''' is the opposite of lossless. A certain amount of data is discarded; how much is usually dependent upon a quality or bitrate setting of the codec. This makes the file (or stream) much smaller that lossless compression, but reduces the [[quality]]. It is impossible to [[transcode]] from one lossy format to another without further degrading quality.

==Lossless Codecs==
* [[WAVE]] (WAVE is technically a container format, but usually contains lossless PCM audio.)
* [[FLAC]]
* [[WAVPACK]]
* [[HuffYUV]] video codec

==Lossy Codecs==
* [[MP3]]
* [[Vorbis]]
* [[AAC]]
* [[AC3]]
* [[WMA]]
* [[Speex]]
* Most [[codecs|video codecs]]

[[Category:Glossary]]

FLAC

2009-10-30T07:49:41Z

DB-tester: fix

{{website|FLAC|http://flac.sourceforge.net}}
{{open}}
'''FLAC''' is short for '''Free Lossless Audio Compression'''. It is an open source [[codec]] and [[file format]] which provides a [[lossless|perfect]] quality audio file. FLAC files usually contain [[CD|CD quality]] audio, but can also support almost any audio data with a wide range of sample frequencies, amount of channels and bits per sample.

FLAC provides a smaller size of file than [[PCM]] [[WAV]] (about half the size), but much larger than [[lossy]] codecs like [[MP3]]. MP3s are about 5-10% the size of WAV files, but are lower quality.

A CD's worth of data is...
* 700MB as a CD
* 700MB as WAV
* '''300MB as FLAC'''
* 40MB as MP3 (128 [[kbps]])

== Container format ==
{{mux|id=flac|encoder=n}}
FLAC can be used inside several [[container formats]], such as [[ogg]] and [[matroska]], but can also be stored in it's own container.

VLC can only decode this type of container, and cannot encode it. To encode files in FLAC format use the flac command line tool from [http://flac.sf.net FLAC's website].

== Source code ==
{{file|modules/demux/flac.c|input demuxer}}

Ogg

2009-10-30T07:45:28Z

DB-tester: fix

{{mux|id=ogg|encoder=y}}
{{wikipedia|Ogg}}
{{open}}
Being a [[Container]] format, ogg can embed third-party codecs (such as [[DivX]], [[XviD]], [[MP3]] and others) but usually Ogg is used with [[Vorbis]], [[Theora]], [[FLAC]] and [[Dirac]].<BR>

== Accepted codecs ==
Below are the compatible codecs for OGG.

=== Accepted audio codecs ===
* [[vorb]]: Vorbis handles general audio data at mid- to high-level bitrates (~16-256 kbit/s/channel)
* [[flac]]: Free lossless audio codec. Has same sound quality as [[wave]], but only cca half the size.
* [[spx]]: Speex handles voice data at low bitrates (~8-32 kbit/s/channel)

=== Accepted video codecs ===
* [[theo]]: Theora based upon On2's [[VP3]], it is targeted at competing with MPEG-4 video (i.e. [[DivX]] and [[XviD]]), [[RealVideo]], or [[WMV|Windows Media Video]].
* [[drac]]
* [[tark]] (decoding only): Tarkin, an experimental codec utilizing 3D wavelet transforms. It has been put on hold, with Theora becoming the main focus for video encoding.

* [[mpgv]]: MPEG
* [[mp4v]]: MPEG-4
* [[div3]]: DIVX 3
* [[mjpg]]: MPJPEG video
* [[wmv1]], [[wmv2]], [[wmv3]]: Windows media
* [[snow]]
* [[ms]] (decoding only):
* [[xvid]] (decoding only):

=== Meta codecs ===
* [[cmml]] (decoding only): Text information

== Source code ==
{{file|/modules/mux/ogg.c|output muxer}}
{{file|modules/demux/ogg.c|input demuxer}}

== References ==
Some of this page is taken from the Wikipedia article on this subject.

Theora

2009-10-24T10:04:27Z

DB-tester: citation needed

{{codec video|id=theora|for=[[ogg]] and [[matroska]]}}

'''Theora''' is an open video codec based on [[On2]]'s [[VP3]] codec, open sourced in 2001.

It's being developed by the [http://www.xiph.org/ Xiph.org foundation] of [[Ogg]] and [[Vorbis]] fame. If you want to be sure there are no legal issues with your software, Theora is a good choice, altough it's technically not as advanced as [[MPEG-4]] or [[WMV9]] {{citation needed}}.

Version 1.0 of the codec has been released in 2008 Novembver, in 2009 Septemer version 1.1 came out, improving the encoding quality while preserving full compatibility. The video format is frozen (has been since 2004, but there are buggy videos produced by old encoders around and not playing well ) so it's safe to produce Theora files for future use.

Theora uses the [[Ogg]] container format and is usually combined with [[Vorbis]] audio.

Theora files can be streamed using the [[Icecast]] 2 streaming server, available for most recent Linux distributions.

VideoLAN ships Theora support. There are also builtin support or plugins for other media players such as [[Xine]], [[MPlayer]], [[Helix Player]] and [[Windows Media Player]]. See the [http://www.theora.org/theorafaq.html Theora FAQ] for more info.

== VLC implementation details ==

'''WriteMe'''

== Links ==
* [http://theora.org/ Offical website]
* [http://icecast.org/ Icecast] streaming server
* [http://xiph.org/dshow Ogg Direct Show Filters] lets you play Theora files in many Microsoft Windows applications, including Windows Media Player.

Theora

2009-10-24T10:02:51Z

DB-tester: missed ==

{{codec video|id=theora|for=[[ogg]] and [[matroska]]}}

'''Theora''' is an open video codec based on [[On2]]'s [[VP3]] codec, open sourced in 2001.

It's being developed by the [http://www.xiph.org/ Xiph.org foundation] of [[Ogg]] and [[Vorbis]] fame. If you want to be sure there are no legal issues with your software, Theora is a good choice, altough it's technically not as advanced as [[MPEG-4]] or [[WMV9]].

Version 1.0 of the codec has been released in 2008 Novembver, in 2009 Septemer version 1.1 came out, improving the encoding quality while preserving full compatibility. The video format is frozen (has been since 2004, but there are buggy videos produced by old encoders around and not playing well ) so it's safe to produce Theora files for future use.

Theora uses the [[Ogg]] container format and is usually combined with [[Vorbis]] audio.

Theora files can be streamed using the [[Icecast]] 2 streaming server, available for most recent Linux distributions.

VideoLAN ships Theora support. There are also builtin support or plugins for other media players such as [[Xine]], [[MPlayer]], [[Helix Player]] and [[Windows Media Player]]. See the [http://www.theora.org/theorafaq.html Theora FAQ] for more info.

== VLC implementation details ==

'''WriteMe'''

== Links ==
* [http://theora.org/ Offical website]
* [http://icecast.org/ Icecast] streaming server
* [http://xiph.org/dshow Ogg Direct Show Filters] lets you play Theora files in many Microsoft Windows applications, including Windows Media Player.

Theora

2009-10-24T10:01:47Z

DB-tester: 1.1 is better

{{codec video|id=theora|for=[[ogg]] and [[matroska]]}}

'''Theora''' is an open video codec based on [[On2]]'s [[VP3]] codec, open sourced in 2001.

It's being developed by the [http://www.xiph.org/ Xiph.org foundation] of [[Ogg]] and [[Vorbis]] fame. If you want to be sure there are no legal issues with your software, Theora is a good choice, altough it's technically not as advanced as [[MPEG-4]] or [[WMV9]].

Version 1.0 of the codec has been released in 2008 Novembver, in 2009 Septemer version 1.1 came out, improving the encoding quality while preserving full compatibility. The video format is frozen (has been since 2004, but there are buggy videos produced by old encoders around and not playing well ) so it's safe to produce Theora files for future use.

Theora uses the [[Ogg]] container format and is usually combined with [[Vorbis]] audio.

Theora files can be streamed using the [[Icecast]] 2 streaming server, available for most recent Linux distributions.

VideoLAN ships Theora support. There are also builtin support or plugins for other media players such as [[Xine]], [[MPlayer]], [[Helix Player]] and [[Windows Media Player]]. See the [http://www.theora.org/theorafaq.html Theora FAQ] for more info.

== VLC implementation details

'''WriteMe'''

== Links ==
* [http://theora.org/ Offical website]
* [http://icecast.org/ Icecast] streaming server
* [http://xiph.org/dshow Ogg Direct Show Filters] lets you play Theora files in many Microsoft Windows applications, including Windows Media Player.