JVET-T0023 JCT-VC AHG report: Software development and software technical evaluation (AHG3) [K. Sühring, B. Li, K. Sharman, V. Seregin, G. Tech, A. Tourapis]

This AHG report was discussed at 0605 Friday 9 October 2020 (chaired by GJS & JRO).

This report summarizes the activities of the JCT-VC AhG on HEVC, AVC and HDRTools software development and software technical evaluation that have taken place between the 39th and 40th JCT-VC meetings.

There had not been any releases of software during the reporting period.

The software model versions prior to the start of the meeting were:

• HM-16.22 (July 2020)
  • (svn HM 16.20 (Sep. 2018))
• HM-16.21+SCM-8.8 (Mar. 2020)
  • (svn HM 16.20 + SCM 8.8 (Mar. 2018))
• SHM 12.4 (Jan. 2018) [svn]
• HTM 16.3 (July 2018) [svn]
• JM 19.0
• JSVM 9.19.15 (Note that this item was recently recovered)
• JMVC 8.5 (Note that this item was recently recovered)
• 3DV ATM 15.0
• HDRTools 0.19.1 (Sep. 2019)

A repository containing MFC and MFCD had not been identified.

Post-meeting note: MFC and MFCD software Zip packages are published as part of Rec. ITU-T H.264.2 (02/2016) at https://www.itu.int/rec/T-REC-H.264.2, and are presumably also available in the corresponding ISO/IEC publication.

HM related activities

HM16.22 was tagged on July 3, 2020. Changes included:

• JCTVC-AK0030 (Change to random-access encoder configuration).
• Changes to LowDelay GOP-8 QP structure to match those used by VTM.
• JCTVC-AK1005 (Shutter interval information SEI)
• Additional checks to warn if DPB limits would be exceeded by a configuration.
• Porting of JVET’s parcat software for concatenating simulations run in parallel.
• Removal of macros.
• Updates to the software reference manual for the new cmake build process.
• Addition of encoder controls for some SEIs (from author of Shutter interval SEI), namely ambient view environment SEI, content light level SEI, and film grain characteristics SEI.
• Shutter interval info SEI message.

The following actions had yet to be included:

• JCTVC-AM0023 (Illustration of the film grain characteristics SEI message in HEVC) – a merge request had been made, and the software coordinators had made a first pass of the software; a second pass is required to verify the function.
• JCTVC-AJ0028 (Encoder-only Supplemental Motion Vector Estimation for Point cloud Coding content) – some minor changes remain.

As reported in the previous report, further information on lambda optimization in HM would be appreciated, including comparison of allocation of bits within the GOP structures between HM and VTM.

Except for the addition above, the support of SEI messages had not changed and is summarized in JCTVC-AM0003. It was noted that the SEI manifest SEI message software support was not yet in the HM, although it may be in the JSVM. It was commented that some software may have been provided for that at the Marrakech meeting of 2019-01.

The HEVC bug tracker listed:

• 39 tickets for “HM”, most of which are more than 5 years (see in particular a recent ticket about CABAC termination),
• 1 ticket for “HM RExt”, which was created during this reporting period,
• 7 tickets for “HM SCC”, all of which are at least 3 years old,

Help to address these tickets would be appreciated.

Codebases without recent action

• SCC SCM
• SHM
• HTM of MV-HEVC and 3D-HEVC
• HDRTools
• JM, JSVM, JMVM

The AHG recommended to:

• Continue to develop reference software based on HM 16.22, HM 16.21 + SCM 8.8, SHM 12.4, HTM 16.3 and HDRTools 0.19.1 and improve their quality.
• Test the reference software more extensively outside of common test conditions.
• Add more conformance checks to the decoder to more easily identify non-conforming bit-streams, especially for profile and level constraints.
• Encourage people who are implementing HEVC based products to report all (potential) bugs that they are finding in that process.
• Encourage people to submit bit-streams that trigger bugs in the HM. Such bit-streams may also be useful for the conformance specification.
• Encourage people to submit configuration files that trigger bugs in HDRTools.
• Continue to investigate the merging of branches.
• Keep common test conditions aligned for the different standards.

It was suggested to merge the two software maintenance AHGs.