JVET-R0139 AHG9: High-level control flag for lossless coding [T. Zhou, E. Sasaki, T. Ikai (Sharp)]
This contribution proposes a high-level control flag for lossless coding in VVC. It includes two options:
Option 1: A sequence parameter set (SPS) level flag for lossless mode
Option 2: A picture parameter set (PPS) level flag for lossless mode
In both cases, some applicable flags that are always constant in lossless mode are not signalled when the proposed lossless flag is equal to 1. It is asserted that the proposed syntax can be beneficial for sequence or picture level lossless case and it avoids useless flag signalling in lossless coding case.
The intent is for entire-picture lossless coding.
The motivation is inferring the disabling of tools that disallow lossless coding at SPS and PPS, such that various other flags can be saved
Further, there is a low-level change which saves the TS flag at CU level.
The saving of HLS information is not relevant, and even more for lossless coding
Entire-picture lossless coding is not a relevant application for VVC (due to high complexity, and level constraints).
No action was taken on this.