The MPEG-VCEG Joint Video Exploration Team has concluded that the latest round of testing and evaluation shows that evidence exists of a potential to build a new standard that could significantly outperform HEVC.
At the 119th MPEG meeting, responses to the previously issued call for evidence have been evaluated and they have all successfully demonstrated evidence. The call requested responses for use cases of video coding technology in three categories:
- standard dynamic range (SDR) — two responses;
- high dynamic range (HDR) — two responses; and
- 360° omnidirectional video — four responses.
The evaluation of the responses included subjective testing and an assessment of the performance of the “Joint Exploration Model” (JEM).
The results indicate significant gains over HEVC for a considerable number of test cases with comparable subjective quality at 40-50% less bit rate compared to HEVC for the SDR and HDR test cases with some positive outliers (i.e., higher bit rate savings). Thus, the MPEG-VCEG Joint Video Exploration Team (JVET) concluded that evidence exists of compression technology that may significantly outperform HEVC after further development to establish a new standard. As a next step, the plan is to issue a call for proposals at 120th MPEG meeting (October 2017) and responses expected to be evaluated at the 122th MPEG meeting (April 2018).
Call for Evidence on Transcoding for Network Distributed Video Coding
The call for evidence on transcoding for network distributed video coding targets interested parties possessing technology providing transcoding of video at lower computational complexity than transcoding done using a full re-encode. The primary application is adaptive bitrate streaming where a highest bitrate stream is transcoded into lower bitrate streams. It is expected that responses may use “side streams” (or side information, some may call it metadata) accompanying the highest bitrate stream to assist in the transcoding process. MPEG expects submissions for the 120th MPEG meeting where compression efficiency and computational complexity will be assessed.
Storage of Sample Variants (2nd edition) reaches Committee Draft
Sample variants are typically used to provide forensic information in the rendered sample data that can, for example, identify the specific Digital Rights Management (DRM) client which has decrypted the content. Sample variants are compatible with MPEG common encryption (CENC) and agnostic to the employed particular forensic marking system. The second edition expands its usage to MPEG-2 transport stream whereas the first edition primarily focused on ISO base media file format.
New Technical Report for HDR/WCG Video Coding
The new technical report (TR) for high dynamic range (HDR) and wide colour gamut (WCG) video coding comprises a survey of various signaling mechanisms including backward compatibility and display adaptation, In particular, a dual-layer coding approach using the Scalable Main 10 profile of HEVC for backward compatibility with standard dynamic range (SDR) systems is also documented.
Hybrid Natural/Synthetic Scene Data Container
MPEG issues draft requirements for a scene representation media container enabling the interchange of content for authoring and rendering rich immersive experiences. This activity is currently referred to as hybrid natural/synthetic scene (HNSS) data container and should provide means for scene graph data representation and the associated container for media that can be rendered to deliver photorealistic hybrid scenes, including scenes that obey the natural flows of light, energy propagation and physical kinematic operations. The container will support various types of media that can be rendered together, including volumetric media that is computer generated or captured from the real world.
Other MPEG (Systems) activities at the 119th meeting is briefly summarized in the following:
DASH is in fully maintenance mode as only minor enhancements/corrections have been discussed including contributions to conformance and reference software. The omnidirectional media format (OMAF) is certainly the hottest topic within MPEG systems which is actually between two stages (i.e., between DIS and FDIS) and, thus, a study of DIS has been approved and national bodies are kindly requested to take this into account when casting their votes (incl. comments). The study of DIS comprises format definitions with respect to coding and storage of omnidirectional media including audio and video (aka 360°). The common media application format (CMAF) has been ratified at the last meeting and awaits publications by ISO. In the meantime CMAF is focusing on conformance and reference software as well as amendments regarding various media profiles. Finally, requirements for a multi-image application format (MiAF) are available since the last meeting and at the 119th MPEG meeting a work draft has been approved. MiAF will be based on HEIF and the goal is to define additional constraints to simplify its file format options.
Bitmovin has successfully demonstrated live 360 adaptive streaming as described here and expects various improvements from standards available and under development of MPEG. We are therefore fully committed in contributing to relevant MPEG activities in the future.
The 119th MPEG meeting concluded on July 21, 2017 in Turin, Italy with the following topics:
- Evidence of New Developments in Video Compression Coding
- Call for Evidence on Transcoding for Network Distributed Video Coding
- 2nd Edition of Storage of Sample Variants reaches Committee Draft
- New Technical Report on Signalling, Backward Compatibility and Display Adaptation for HDR/WCG Video Coding
- Draft Requirements for Hybrid Natural/Synthetic Scene Data Container
The corresponding press release of the 119th MPEG meeting can be found here: http://mpeg.chiariglione.org/meetings/119
