JVET-AJ0145 AHG7: Inter tool assessments for each ECM version [R. Ishimoto, Z. Fan, T. Chujoh, T. Ikai (Sharp)]

ECM keeps getting updates and the latest one is version 14. This report analyzes the trends in coding efficiency gain (Gain), decoding time, and encoding time of major inter tools for each version of ECM, highlighting which areas have improved in the evolution of ECM. This report is focused more on individual tools rather than group-off experiments. This experiment was conducted by turning off one target tool and seeing the difference to CTC anchor, a.k.a. off tests. This result is the average of RA of class B and C of CTC (class A is excluded due to massive encoding time).

This was a contribution for information. It was an interesting study assessing how the benefit of inter tools evolved over time. It was pointed out that it is in some cases not simple to disable individual tools.

With regard to AHG7 activities, it was agreed to establish a new group of tools with large memory access, e.g by needing large lookup tables. It is however also necessary to take into account the granularity of usage, e.g. it is different if a large amount of coefficient values needs to be reloaded for every 4x4 block or for an entire CTU.

A BoG (X. Li) was tasked to further work on criteria, and set up a list of tools that would be added to such a group.