frontends/va: improve enc quality interface change
why: to enhance va video encoding quality
how: use va encoding quality_level interface, and provide default value and encoding quality adjustment options, so that users can finetune encoding quality and performance from va quality interface.
There are 3 settings added:
-- preset modes: speed, balance, quality
they are using different encoding strategies
-- vbaq modes: vbaq mode is using variance based strategy
to improve the subjective image quality
-- pre-encoding modes:
Using scaled down input image for pre-encoding to have
better rate-control reaction and consume more memory
in the same time. Only preencoding-4x mode is enabled.
Signed-off-by: Ruijing Dong ruijing.dong@amd.com