H.263
From Academic Kids
H.263 is a video codec designed by the ITU-T as a low-bitrate encoding solution for videoconferencing. It was first designed to be utilized in H.324 based systems (PSTN and other circuit-switched network videoconferencing and videotelephony), but has since found use in H.323 (RTP/IP-based videoconferencing), H.320 (ISDN-based videoconferencing), RTSP (streaming media) and SIP (Internet conferencing) solutions as well.
H.263 was developed as an evolutionary improvement based on experience from H.261, the previous ITU-T standard for video compression, and the MPEG-1 and MPEG-2 standards. Its first version was completed in 1995 and provided a suitable replacement for H.261 at all bitrates. It was further enhanced in projects known as H.263v2 (a.k.a. H.263+ or H.263 1998) and H.263v3 (a.k.a. H.263++ or H.263 2000).
The next enhanced codec developed by the ITU-T (in partnership with MPEG) after H.263 is the H.264 standard, also known as AVC and MPEG-4 part 10. As H.264 provides a significant improvement in capability beyond H.263, the H.263 standard is now considered primarily a legacy design (although this is a recent development). Most new videoconferencing products now include H.264 as well as H.263 and H.261 capabilities.
For more information on H.263, see the following sources:
External link
- H.263 Video Coding Comparison (http://www-mobile.ecs.soton.ac.uk/peter/h263/h263.html)
- IETF AVT Working Group (http://www.ietf.org/html.charters/avt-charter.html) - Group that reviews codec packetizations for RTP
- RTP Payload Format for H.263 Video Streams (RFC 2190) (http://www.ietf.org/rfc/rfc2190.txt)
- RTP Payload Format for the 1998 Version of ITU-T Rec. H.263 Video (H.263+) (RFC 2429) (http://www.ietf.org/rfc/rfc2429.txt)
- Find H.263 specification on ITU website (http://www.itu.int/itudoc/itu-t/rec/h/)
- Intel's H.263 codec installer for Windows (http://support.intel.com/support/createshare/camerapack/CODINSTL.HTM)
- I263 video codec (http://members.aol.com/SlavTrainr/STsPage.html)
- H.263 Specifications (http://standards.pictel.com/ftp/video-site/)
- H.263 implementation in vic (source code available) (http://www4.informatik.uni-erlangen.de/Projects/ScalVico/vic/)
- SourceForge Project to create H.263 codec (http://sourceforge.net/projects/openh263-s/)
- Video Demystified (http://www.video-demystified.com/) - Book which includes info about H.263fr:H.263
