JVET-AO0120 AHG9: Historical Information SEI message [J. Pardo, A. Karabutov, H. You, A. Boev, J. Sauer, T. Solovyev, E. Alshina (Huawei)]

Chaired on 22 January from 16:55-17:20 chaired by S. Deshpande.

Following CfE and CfP sequences selection it was suggested that user-generated content (UGC) is likely to play a bigger role in the development of the next video codec standard than in past projects. It is proposed that UGC sequences characteristics should be also considered in the VSEI tracks. One of these characteristics that is proposed is to add transcoding information

It was commented that the text description information (TDI) SEI message can be used which has a purpose related to it- encoder description. Or we can add a specific purpose. Also multiple TDI SEI messages with different IDs could be used to track history.

It was commented that there may be additional processing in addition to transcoding such as resolution resampling, frame rate conversion, bit depth change etc. and those may also be unknown.

It was commented that the encoder optimization information (EOI) SEI message may also be potentially considered to describe the type of transcoding done and other type of pre-processing and post-processing, denoising, sharpening, etc.

It was commented if the history can be potentially be used for improving current encoding process, then the expectation is all the chain is kept intact and not lost. If that is not true then the information could be misleading.

A comment was made it is not entirely clear how the information about previous transcoding(s) can really help a new encoding (as proposed). It was commented that knowing information such as partitioning, CTU size etc. of previous encoding could help in faster encoding subsequently.

It was commented that JVET-AN0247 had some relation to this use case. Additionally JVET-AO0116 is also related.

Further study was recommended.