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High Definition Video Is Coming To H.323-Based Videoconferencing. Larry Amiot Northwestern University amiot@northwestern.edu. Broadcast High Definition TV. Breathtaking video quality on home monitors Plasma LCD and projection LCD Projection DLP Several carriers Through the air Cable
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High Definition Video Is Coming To H.323-Based Videoconferencing Larry Amiot Northwestern University amiot@northwestern.edu
Broadcast High Definition TV • Breathtaking video quality on home monitors • Plasma • LCD and projection LCD • Projection DLP • Several carriers • Through the air • Cable • Satellite dish
Broadcast High Definition TV • High Definition is here to stay! • High definition is fast replacing standard definition TV! • Standard definition • 704x480 • 4x3 aspect ratio • Two high definition standard formats • 720p (1280x720) • 1080i (1920x1080) • Both 16x9 aspect ratio
H.323-based Videoconferencing • Compression/decompression architectures • Initially blurred and murky H.261 codecs • Major use today is H.263 • Beginning to see H.264 (MPEG4) • Bandwidth requirements have been low (typically 1 Mbps or less)
H.323-based Videoconferencing • Resolutions have been limited • Typically CIF (352x288) • Recent use of 4CIF (704x576 )- e.g. the Gigaconference requiring bandwidths of 1 to 4 Mbps • Aspect ratio of 4x3 • Several audio algorithms, but typically low quality at 64 Kbps
High Definition H.323-based Videoconferencing • High definition videoconferencing is on the horizon • H.323-based high definition video and audio provides the quality necessary for media rich collaboration • Being standards-based, it offers • User simplicity • Promise of interoperability with other non-high definition H.323 systems
LifeSize H.323-Based Room Unit • Produces 720p high definition video • Utilizing H.264 codec • 16x9 aspect ratio • 9CIF quality • 1 Mbps bandwidth (can go at 2 Mbps point to point)
LifeSize H.323-Based Room Unit • Built-in 4 port MCU • Good acoustical quality • omni-directional architecture • circular array of 16 microphones • 100 Hz up to 22 kHz bandwidth • High definition camera with 70 degree field of view
Other High Quality Video Options • MPEG2 • VBrick, StarValley, etc • High quality video in the 7 to 16 Mbps range • Used at Northwestern for remote venues • DVTS • Lot of work being done in the Big Video project • Transports digital video over IP at 30 Mbps
Other High Quality Video Options • HDV • MPEG2 compressed High definition video • 20 Mbps transfer rates • Uncompressed high definition video • Highest quality video of all • 720p requires transmission rate of 165 Mpixels per second • Requires special equipment to handle streams • Access Grid high definition experiments • Microsoft ConfernceXP • MPEG4 compressed high definition
What Are The Driving Forces? • Do you need high definition resolution? • How important is audio quality? • Is aspect ratio important • Do you have sufficient bandwidth? • Do you need two way interaction (conferencing)? • Is H.323 interoperability important? • What can you afford?