IBC 2010 – Data Compression – Paul Dempsey

 At IBC in Amsterdam, there was a discussion on video compress for digital data broadcast for consumer use of television. This discussion was based on the further conversion of channels from SD to HD and eventually HD3D. There are several compression methods an each has an associated standard and or codec.

The discussions indicated that we are on course for a further twofold reduction in video compression bit rates without having to resort to any revolutionary of new techniques, according to one of the academics leading the current ITU/MPEG effort.

Jens-Rainer Ohm, co-chair of the team developing the High Efficiency Video Coding (HEVC) standard, told an IBC technical session that it is reviewing submissions that are already achieving a 35-40% bit rate reduction benchmarked against the Advanced Video Coding (AVC) standard.

James Ranier Ohm

HEVC is intended to enable incoming resolutions such as ultra high-definition (UHD), 4K and 8K video, and also full two-frame 3D over multi-view transmissions. All of these will quickly exhaust available transmission capacity.

“We need a substantially greater bit rate reduction over the reduction we saw for H.264 (aka AVC),” said Ohm, whose Joint Collaborative Team on Video Coding formally began work in January on the issue and has already begun to evaluate more than 25 different proposals.

Ohm noted that while HEVC was shaping up to be so different from AVC that it would not be an extension of that standard but a new one, there were many similarities.

“Everything is bread and butter technology, but done much better,” he said. “There are some new concepts in entropy coding and much more parts concerned with motion compensation, but there is not that much. Some of these things go back to the 1990s.”
Familiar concepts such as flexible picture buffering, quadtree structures and adaptive loop filters are being exploited.

“There is still a lot of work to do to develop a standard of the necessary quality,” said Ohm, “but the aim is to have at least a first version available in 2012.”

The ITU/MPEG effort is not the only one under way in this field. Germany’s Fraunhofer Institute, developer of MP3 compression, is also pitching a technology aimed at 3D and other content requiring a higher data rate than is viable with existing codecs. It demonstrated its Multiview Video Coding technology at IBC, concentrating on Internet and satellite delivery.