intel / intel-vaapi-driver

VA-API user mode driver for Intel GEN Graphics family
https://01.org/linuxmedia
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gen9_vp9_encoder: Relax the compressed frames minimum size restriction. #508

Closed sreerenjb closed 4 years ago

sreerenjb commented 4 years ago

The current implementation of the CQP mode encode has a compressed buffer size restriction of 4Kb. The restriction doesn't make sense for low-resolution & low-bitrate video encoding use cases since inter-frames can be encoded with much less number of bytes.

For eg: most of the P-frames in a video-conferencing session of 640x480 resolution at 750kbps require only 1Kb bitrate allocation and currently the hardware PAK unit fill the rest of the 3Kb (4Kb-1Kb) with zeros. This will jeopardize the quality & bit-rate allocation of the hybrid CBR encode models1 where we run the bitrate control algorithm in software clubbed with a CQP hardware encoder: