Video Compression
From P2P Foundation
Definition
"Video Compression refers to the methods for reducing the quantity of data used to represent video. It is a straight forward combination of image compression and motion compensation. To compress a video file we need two things: a video Codec and a video editing tool." (http://xylem.aegean.gr/~modestos/mo.blog/)
Examples
- "Theora is a video compression technology being developed by the Xiph.Org Foundation as part of their Ogg project. Based upon On2 Technologies’ VP3 codec, and christened by On2 as the successor in VP3’s lineage, Theora is targeted at competing with MPEG-4 video (e.g., the x264, Xvid and DivX codecs), RealVideo, Windows Media Video, and similar lower-bitrate video compression schemes. Xiph and Theora are considered the most promising projects for video compression. mainly supported by linux/unix operating systems. It supports playback for Linux, MacOS and Windows. You can use this player: VLC"
(http://xylem.aegean.gr/~modestos/mo.blog/)
- http://TheoraSea.org share video and audio similar to YouTube
- http://Dirac.sf.net Dirac is a video codec that provides general-purpose video compression and decompression tools comparable with state-of-the-art systems. Dirac is a format and a compression technology, not a specific codec.
- http://Schrodinger.sf.net The Schrödinger project will implement portable libraries for the high quality Dirac video codec created by BBC Research and Development. Dirac is a free and open source codec producing very high image quality video.
- Xvid: http://Xvid.org is an open-source research project focusing on video compression and is a collaborative development effort. All code is released under the terms of the GNU GPL license.
- The Xvid video codec implements MPEG-4 Simple Profile and Advanced Simple Profile standards. It permits compressing and decompressing digital video in order to reduce the required bandwidth of video data for transmission over computer networks or efficient storage on CDs or DVDs. Due to its unrivalled quality Xvid has gained great popularity and is used in many other GPLed applications, like e.g. Transcode, MEncoder, MPlayer, Xine and many more.
- Most people have it installed, so by using this codec it is almost certain that your videos will be playable everywhere. It is available on GNU/Linux, MacOSX and Windows.
- Notice 'Xvid' is 'Divx' spelled backward - where Divx is a proprietary video Codec.
- x264: a free software library for encoding H.264/MPEG-4 AVC video streams. As of May 2007, x264 is one of the most advanced publicly available AVC encoders. It is supported by Linux, MacOS and Windows."
