The DVB Project Office is located in the European Broadcasting Union headquarters in Geneva.
The DVB (Digital Video Broadcasting) Project has selected three candidate codecs for inclusion in its standards and is conducting tests on each for technical compliance before developing draft specifications.
The candidates are MPEG’s VVC (Versatile Video Coding), AOMedia’s AV1 and the Chinese AVS3.
Inclusion of AVS3 surprised some observers but was consistent with the DVB’s acceptance that we are now in a multi-codec world and that it should embrace the three standards groups that have gained widespread traction in various countries. Including AVS3 was a diplomatic step that also advances DVB’s ambitions to be a global rather than just European arbiter of broadcasting standards.
The DVB has been conducting preparatory technical studies for some months now, driven by demand to support 4K and even 8K services within anticipated bandwidth constraints. Work to evaluate technical compliance and development of draft DVB specifications will now begin, starting with MPEG’s VVC before moving on to the other two codecs.
Specific targets have been set to meet bandwidth requirements, with the new codecs expected to save at least 27% in bit rate for a given quality compared to the existing HEVC codec in 4K broadcast delivery, and at least 30% for 4K in broadband streaming. There are also expectations that the codecs will improve compression efficiency at lower resolutions to reduce environmental impact when delivering to devices that do not support 4K or 8K resolutions, or where they are not required.
Further, the DVB is insisting that the codecs are aligned with conformance points adopted by relevant standards bodies leading towards its own DVB-I specifications for delivery of linear broadcast services over the internet. The objective of DVB-I is to ensure that quality of experience for broadcast services over the internet is just as good as it is via traditional media, that is satellite, cable, digital terrestrial, or IPTV.
“DVB is a pioneer in the development of media distribution systems and it is preparing the way for advanced 4K and 8K systems in the future” said Peter MacAvock, Chair of the DVB Project. “The industry is watching our work closely and we are confident that DVB will again break new ground on television technology. We encourage all companies with a stake in this field to join our work.”
Until a decade ago, MPEG ruled the codec world with an iron hand and the DVB only had to support one set of standards. AVC, otherwise known as H.264 or MPEG-4 Part 10, had been MPEG’s most successful standard yet, achieving sufficiently great improvement over its predecessors, MPEG-2 and then MPEG-4 Visual, to handle the transition from standard definition to HD.
HEVC looked like being equally successful in succeeding AVC when it was launched in 2012, but then various lurking problems surfaced. A major issue was growing uncertainty over patents which bogged the codec down and deterred many newer service providers especially from making what looked like a risky migration.
Google moved to exploit this loss of faith and momentum behind the MPEG movement by launching its VP9 quickly ahead of schedule, recruiting powerful allies such as Netflix. Immediately VP9 became a strong contender, and AOMedia was formed as a powerful body determined to advance the codec further with development of AV1.
The Chinese meanwhile were emboldened to push their family of codecs more strongly, with AVS3 emerging as the third generation developed by the country’s AVS working group. It has been designed partly for UHD TV broadcasting as the other DVB candidates were, but also for video surveillance, a major field in China. Various comparative tests have been performed and broadly the three codecs are comparable, as well being more or less in the same generational cycle. AOMedia is perhaps closest to its next generation with AV2 already under development as a successor to AV1.
AOMedia has set out its stall as being an open standard not constrained by licensing and while that is open to question, it is true that it has come to market faster than VVC, already being available for streaming, as well as web conferencing following Cisco’s support for the codec on WebEx. AV1 is now enabled on Cisco’s WebEx when sharing high-motion content on desktop machines, replacing H.264, enabling higher video quality when sharing high motion graphics or videos.
It is worth noting the fragmentation of the codec field that is now accepted by DVB has drawn criticism from some key industry players. For example Haivision, a low latency streaming technology specialist, has argued that codec wars have bred more confusion than progress and that the promotion of AV1 has held back progression of HEVC. But the industry is now resigned to the multi codec reality.
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