Organisation internationale de normalisation

CICP

The texts of 23001-8/COR1 and 23001-8/DAM2 (Sample aspect ratio and additional transfer functions, colour primaries and matrix coefficients) were progressed. The latter contains further alignments with the most recent descriptors in HEVC.

8. Green Metadata

A joint meeting with the System SG was held Thu 1200-1300. The following documents were discussed during this meeting:

13.0.0.1.1.1.1.1.43m34977 Efficient Carriage of Green Metadata in an AVC SEI Message [Felix C. Fernandes, Spencer Cheng]

New version of AVC SEI (wrapper which refers to a certain codepoint in AVC)

Numbers of non-zero, intra coded etc. are expressed via 8-bit (interpreted as percentages), not absolute numbers

Second type: Quality metrics

It was discussed whether it is necessary to describe the generation of the values to the large extent suggested here.

The SEI message has been balloted along with the DIS, and support is given by NBs to apply the changes

13.0.0.1.1.1.1.1.44m35163 Revised HEVC SEI Message for Green Metadata [Spencer Cheng, Jiangtao Wen]

Subset of 34977 (only the quality metrics), no separate presentation/discussion necessary.

13.0.0.1.1.1.1.1.45m35148 Best Effort Decoding for Green MPEG - An example application [Alexis Michael Tourapis, David Singer, Krasimir Kolarov, Steve Saunders]

Basic idea: Saving some decoding complexity (e.g. skipping deblocking, rounding MV to full-pel) i.e. perform non-normative decoding which introduces drift. This introduces drift, and potential is shown that it can be minimizes when by purpose being applied closer to the end of the GoP. The contribution presents initial ideas, not meant as concrete proposal for standardization.

Question: Is there a way to control the maximum drop in quality? Further study on this may be required.

9.