International organisation for standardisation organisation internationale de normalisation

Draft text specification of version 1

See also JCTVC-L0363 regarding clarity of text relating to slice_temporal_mvp_enable_flag and request for review of editors' notes in JCTVC-L0030.

4.2.0.1.1.1.1.1.115JCTVC-L0030 Proposed Editorial Improvements for High efficiency video coding (HEVC) Text Specification Draft 9 (SoDIS) [B. Bross, G. J. Sullivan, Y.-K. Wang]

This contribution contained proposed editorial improvement (and corrections) relative to the output text of the previous meeting.

Decision (Ed.): Adopted as the basis for the output text.

Note: Contains "[Ed" comments for review (delegated to the editor as noted in notes for L0363).

4. HEVC coding performance, implementation demonstrations and design analysis

   1. Coding performance

Contributions in this section were appreciated and available for study.

4.2.0.1.1.1.1.1.116JCTVC-L0041 AHG4: Performance evaluation of HEVC on still picture coding [K. Ugur, J. Lainema (Nokia)]

4.2.0.1.1.1.1.1.117JCTVC-L0380 AHG4: Subjective evaluation of HEVC intra coding for still image compression [Philippe Hanhart, Martin Rerabek, Pavel Korsunov, Touradj Ebrahimi (EPFL)] [late]
4.2.0.1.1.1.1.1.118JCTVC-L0322 Comparison of Compression Performance of HEVC Draft 9 with AVC High Profile and Performance of HM9.0 with Temporal Scalability Characteristics [B. Li (USTC), G. J. Sullivan, J. Xu (Microsoft)]
4.2.0.1.1.1.1.1.119JCTVC-L0304 Crosscheck for HM9.0 with temporal scalability characteristics (JCTVC-L0322) [W. Zhang, L. Xu, Y. Han, Z. Deng, X. Cai, Y. Chiu (Intel)] [late]

2. Implementation demonstrations

4.2.0.1.1.1.1.1.120JCTVC-L0096 Implementation of a HEVC hardware decoder [S. Cho, H. Kim (ETRI)] [late]

A demonstration was shown during the meeting.

4.2.0.1.1.1.1.1.121JCTVC-L0098 On software complexity: decoding 4K60p content on a laptop [T. K. Tan, Y. Suzuki (NTT DOCOMO), F. Bossen (DOCOMO Innovations)]

Experiments with parallelism achieved 4K60p using 3 decoding threads (using CRA-based GOP-level parallelism), including display @ 12 Mbps (not using tiles or wavefronts, but using lots of RAM). Up to 100 fps. (720p up to 300 fps.)

4.2.0.1.1.1.1.1.122JCTVC-L0379 HEVC Real-time Hardware Encoder for HDTV signal [A. Minezawa, H. Sakate, N. Motoyama, S. Sekiguchi (Mitsubishi), Y. Sugito, K. Iguchi, A. Ichigaya, S. Sakaida (NHK)] [late]

This contribution is to provide information on a development of hardware encoder implementation based on HEVC coding tools. The developed encoder is a FPGA-based prototype system that supports real-time encoding of 1080@60P with Main 10 profile level functionality, and it was reported that it can achieve significant coding gain relative to existing professional-class AVC encoder products.

3. Design analysis

4.2.0.1.1.1.1.1.123JCTVC-L0332 Dynamic Range Analysis of HEVC Inverse Transform Operations [Louis Kerofsky (Sharp), Shevach Riabtsev (CSR)]

Information document available for study – relevant to range extensions.

5. Profile, level, and constraint definitions (for version 1 of HEVC)

4.2.0.1.1.1.1.1.124JCTVC-L0244 Main 10 Still Picture Profile [C. Auyeung, A. Tabatabai, T. Suzuki (Sony)]

This is a profile proposal that would need parent-body discussion and approval for action. No action taken, pending parent-body input indicating otherwise.

4.2.0.1.1.1.1.1.125JCTVC-L0277 Suggested Modifications for Still Picture Profile [K. Sato (Sony)]

The draft text includes a Main Still Picture profile. If an image is coded with the Main Still Picture profile, transmission of information on HRD, temporal layer, or inter-coding tools is asserted to be unnecessary.

This document proposes to require various syntax elements (those that are unnecessary for still pictures) to be absent or set to particular values in bitstreams conforming to the Main Still Picture profile.

It was commented that the proposed restrictions would prohibit extracting an intra picture from a Main profile bitstream and using it as a Main Still Picture profile bitstream. No action was taken on this.

4.2.0.1.1.1.1.1.126JCTVC-L0292 AHG9: On LCU bit size limit [W. Zhang, L. Xu, Y. Chiu, L. Liu (Intel)]

This report proposes the maximum expansion ratio of LCU bit size to be increased to 3/2 for Main Profile and Main Still Picture Profile and 5/3 for Main 10 Profile, to avoid the violation found in simulations. In HEVC draft 9, the maximum expansion ratio of LCU bit size is limited to be equal to 4/3. This proposal investigates the impact of this constraint by studying the synthesized "SandStorms" testing sequence with Gaussian white noise. Simulation results reportedly show that a number of violations exceeding the LCU bit size limit with expansion ratio of 4/3 are observed. The violation problem is reportedly worse when transform is turned off. This contribution regards the case without transform skip as the worst cast to increase the LCU bit size limit for encoder to confirm. Further simulation results reportedly show that the proposed LCU bit size limit works well for both scenarios of transform skip on/off.

Decision: Increase bit expansion limit ratio from 4/3 to 5/3 (regardless of profile).

6. Source video test material

4.2.0.1.1.1.1.1.127JCTVC-L0301 AHG8: New 4:4:4 screen-content sequences for HEVC extension development [H. Yu (Huawei), R. Cohen (MERL), W. Gao (Huawei), Y. Cao, J. Ye, X. Wang, A. Vetro (MERL), H. Sun]

The contribution of additional test sequence material was appreciated.

4.2.0.1.1.1.1.1.128JCTVC-L0317 AHG8: YUV444 and RGB screen content test sequences [Shuhui Wang, Mengcao Jiao, Tao Lin, Kailun Zhou (Tongji U)]

The contribution of additional test sequence material was appreciated.

4.