SMPTE Report: Next-Gen Video Compression on the Horizon
A new generation of potential video services, from 3D to 4K and everything in between, will require a new generation of video coding. And if all goes according to plan, the introduction of HEVC (High Efficiency Video Coding) in 2013 may be the answer, providing twice the efficiency of the current MPEG-4/H.264 standard and four times the efficiency of MPEG-2.
Matthew Goldman, VP, Technology Solution Area TV, for Ericsson, took to the stage at the SMPTE Tech Convention to provide an overview of the work being done related to the potential format and why it matters (editor’s note: he will revisit the topic at the Sports Video Group League Technology Summit during the workshop on next-generation TV Dec. 12 in New York City).
The compression standard is currently under joint development by the ISO/IEC Moving Picture Experts Group (MPEG) and the ITU-T Video Coding Experts Group (VCEG). MPEG and VCEG have established the Joint Collaborative Team on Video Coding (JCT-VC) to develop the HEVC standard.
The reason the format is important? New distribution platforms, such as tablets and phones, continue to become HD-capable, putting new constraints on bandwidth.
“Also, all mobile devices have battery technologies that are improving, but they can always use improvements to lengthen battery life,” Goldman explained. “A new low-complexity mode in HEVC will allow for it to require less power from those devices.”
The current roadmap calls for a committee draft to be nailed down next February, with a final draft of an international standard released in July. The hope is, it will be ready for ratification in January 2013.
“That translates to devices that will first appear in 2013, with more-mainstream devices being introduced in 2014,” he added. “That is not that far off if you are a designer of a set-top box or receiver.”
With next-generation–TV transmission addressed by the Advanced Television System Committee’s TG3 group’s work on ATSC 3.0, a future standard for over-the-air transmission , broadcasters’ ability to leap from MPEG-4 to a system that can handle full-resolution 3D stereoscopic signals, 1080p, and even 4K promises to enable broadcasters to remain competitive with IP, satellite, and cable-delivered TV content.
Among the technical differences from the current MPEG-4 standard is the use of a 64×64 hierarchical quad tree block that allows processing to be partitioned so that the portion of the block that needs the most horsepower gets it: larger sections of the 64×64 block use fewer bits while those needing more details can receive more bits.
“The goal is to eliminate needlessly coded blocks for the highest efficiency,” noted Goldman.
Current tests have shown that efficiency is definitely in the cards. A 480p sequence was found to offer a 44% gain in efficiency compared with MPEG-4, 720p about 30% for a moderately difficult scene, and 1080p had a gain of 42%. And 4K can be compressed into 53% of the bandwidth required for MPEG-4.
“There are commercial benefits for HEVC,” Goldman said. “With future formats like 1080p/60 or full-resolution 3D or 4K TV sets, this is a perfect application.