  The Alliance for Open Media has recently initiated coding tool exploration
activities towards the next-generation video coding beyond AV1. With this
regard, this paper presents a package of coding tools that have been
investigated, implemented and tested on top of the codebase, known as libaom,
which is used for the exploration of next-generation video compression tools.
The proposed tools cover several technical areas based on a traditional hybrid
video coding structure, including block partitioning, prediction, transform and
loop filtering. The proposed coding tools are integrated as a package, and a
combined coding gain over AV1 is demonstrated in this paper. Furthermore, to
better understand the behavior of each tool, besides the combined coding gain,
the tool-on and tool-off tests are also simulated and reported for each
individual coding tool. Experimental results show that, compared to libaom, the
proposed methods achieve an average 8.0% (up to 22.0%) overall BD-rate
reduction for All Intra coding configuration a wide range of image and video
content.
