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- MPEG-H Part 2: HEVC
- MPEG-H Part 3: 3D Audio
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- Compact descriptors for video search
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MPEG-HMPEG-H will be the new umbrella for the High Efficiency Video Coding and the related Systems and Audio standards. The vision for MPEG-H was defined at the 99th meeting in N12312 Context and Objectives of MPEG-H. MPEG foresees the initial standards of MPEG-H to include video coding (HEVC), advanced 3D audio coding and MPEG Media Transport. The Definition of graphics and user interfaces will come later.
SEI Messages for Frame Packing Arrangements There was ongoing concerns about frame packing arrangements (FPA) that enable a display to recognize that the current decoded image is composed of two different frames making up on stereo image pair. With respect to coding, this FPA is transparent. Input from National Bodies on this topic was diverse. After long discussions, WG 11 approved the proposal presented in the Requirements report at the Wednesday plenary that leaves the existing SEI-message on FPA as is and introduces a new FPA that at this point just defines the new Tile FPA. Given that the implementation of SEI messages is optional and this FPA has no impact what so ever on the specification of HEVC, the Requirements group was happy to allocate sufficient time to this important topic. Still Picture Coding HEVC-Intra coding might be as useful as the Advanced Image Coder that JPEG requires. The capabilities of HEVC-Intra coding were discussed. Evaluation of the HEVC performance should be done jointly with JPEG. N13826 Draft Test conditions for HEVC still picture coding performance evaluation is sent to JPEG (N13827) for further clarification and update such that a performance evaluation can be done in the future. The adhoc group N13836 AHG on still image coding using HEVC will also continue to work on this topic. Profiles Several profiles for HEVC were discussed. In conclusion, different colour sampling formats (4:2:0, 4:2:2, 4:4:4) and bit depths 8, 10 and 12 bits will be supported. In order to make HEVC more usable for the camera manufactures, a level 8.5 was created which allows for arbitrary picture sizes without putting a real-time decoding constraint. Interlace At this point, HEVC is capable of coding interlaced material. SEI-messages allow for signalling of interlaced material. Compared to AVC using adaptive frame/field coding, HEVC saves 30% in bitrate for the same objective video quality. If the same subjective video quality is required, HEVC saves 50% of the bitrate compared to AVC. Experiments show that relatively small changes to HEVC (colour motion vector scaling, frame-adaptive frame/field coding …) can reduce the bitrate by 7% to 20% for random access applications and low delay applications, respectively. Before arriving at any conclusion, further study of the HEVC encoder for interlaced material is required. Work continues in the N13835 AHG on Study of interlace coding in HEVC. Liaison statements N13877Liaison statement to the ITU-R WP6B on interlace coded video in HEVC and N13878 Liaison statement to SCTE on interlace coded video in HEVC informing about HEVC performance and ongoing investigations were sent.
MPEG received significant technical contributions in response to its call for proposals on audio coding technologies related to 22.2 channel audio and scene-based Higher Order Ambisonics. Especially the work on 22.2 channel coding was based on support of the Japanese National Body. Only the selection of a new standard for this application will ensure an efficient solution for service providers and customers, which may use broadcast or internet channels to receive contents. Due to the need for program level loudness control which is codec agnostic, MPEG issued N13858 Call for Proposals on Dynamic Range Control Technology.
The adhoc group N13598 AHG on coding non-camera-captured content identified several types of images from medical and satellite application that may benefit from special coding tools within HEVC. At this meeting, we concluded that screen content and medical images are the most likely applications that MPEG will get test material and show evidence that an improved coding performance is possible. Some contributions on screen content coding show that bit rate savings of 50% should be possible for this application. The group prepared N13828 Draft requirements for future extensions of HEVC in coding screen content and medical visual content as well as N13829 Draft call for proposals for coding of screen content and medical visual content. N13834 AHG on coding screen content and medical visual content is charged with gathering test material, evidence and prepare a call for proposals. 
Figure 1 Artifacts when coding screen content
CDVS works on describing contents of an image. This activity wants to extend content description to video. Applications are in video retrieval, computer vision, automotive and other application where many video streams need to be evaluated. Related technology within MPEG can be found in MPEG-7 and video signatures. N13824 Applications and Requirements for CDVS Extension to the Video Domain – “CDVidS” reflects first thoughts towards applications and requirements. The adhoc group N13833 AHG on visual search in video will refine applications and requirements.
Several film studios currently master movies for digital cinema and DVD separately since the colour space of the cinema is much larger than the colour space of a regular TV set. The industry would like to master just one version of the content using the xyz colour space. In order to adapt to the different displays and projectors, transformation hints are desirable which instruct the terminal how to scale the colours of the content to the capabilities of the display. Deploying video in such a way would also allow consumers to actually benefit from a wider colour gamut of a new TV screen. At this point, it is not clear how much HEVC will be affected in case of coding xyz data instead of YUV data. The adhoc group N13831 AHG on Support of XYZ Color Space will gather test material and evidence on the coding performance of HEVC. It is also charged with further developing N13822 Draft Requirements for Full Gamut Content Distribution. Liaison statements were sent to various organisations: N13883 WG11 Liaison on support for HDR in XYZ Color Space.
In response to its call, MPEG received five responses. They cover all but one requirement. There seems to be no interest on Green MPEG in areas other than video coding. The Systems subgroup picked up the work which is evaluated in N13830 Evaluation of the Responses to the CfP on Green MPEG.
A standardized user description may enable customers to have easier access to services. An ontology and schemas need to be standardized. Information for user description includes attributes, activities, interests, status, history, medical data, etc. User Descriptions are used in MPEG-7, MPEG-21, MPEG-M, and MPEG-V. As in previous meetings, MPEG defined again an updated architecture that shows the scope and interfaces of MPEG User Descriptions (Figure 2). Red arrows indicate the signals to be standardized. Accordingly, the request and update function will not be standardized at this time. Modifications of the different databases will not be possible using the upcoming MPEG standard given this architecture. MPEG decided to issue N13879 Call for Proposals on MPEG User Description (MPEG-UD) and related documents N13880 Use Cases for MPEG User Description as well as N13881 Requirements on MPEG User Description. The call will be evaluated at the next meeting. Responses from major service providers are important in order to make this activity a commercial success. 
Figure 2 Architecture for MPEG user descriptions |