What They Say
SMPTE interviewed Matthew Goldman, a SMPTE Fellow and past SMPTE President and previously with MediaKind, about developments in codecs and why there is more proliferation of different technology. He pointed out that in the past, codecs were optimised to make the most of the hardware that was available to decode the stream. However, hardware is no longer the single biggest limiting factor as compression has moved onto software-defined architectures. That allows a lot of different technologies and approaches to optimise not just for efficiency, but also to deal with issues such as licensing and patent pools.
For example, the EVC Essential Video Coding format was developed so that its Baseline Profile is more bitrate efficient than AVC, while being royalty free, and its Main Profile is more bitrate efficient than HEVC, but with far simpler licensing requirements. That makes it an alternative for streaming and OTT use. VVC is optimised for the high end with the ‘ultimate in compression efficiency’ so can be used for 360° video, 8K and VR/AR. LCEVC, on the other hand, is used to boost the performance of AVC or HEVC using an enhancement layer. Goldman said:
” LCEVC is like a steroid for [older] codecs, such as AVC and HEVC.”
Referring to AV1, he said that it is
“a high-performing codec that was developed as a claimed royalty-free alternative to international standard codecs for web-based applications. Its coding efficiency is similar to the EVC Main profile.”
Goldman said that machine learning is also coming to compression but is not yet fully practical because of the processing power needed.
“So, my belief is that AVC and HEVC will continue to be workhorses for the foreseeable future, and LCEVC might provide an opportunity to extend them even further,” he adds. “And now, we will have VVC being the ultimate option [for very data intense UHD, 360-degree video, or virtual reality] content. EVC, due to its commercial use benefits, could eventually replace HEVC.
What We Think
I usually catch up with Matthew Goldman at IBC so hope I may be able to catch up in December when this year’s event takes place. The interview goes into some depth, so is worth a read if compression is a topic you are interested in. (BR)
