lavc/vaapi_encode: add support for maxframesize

Add support for max frame size:
    - max_frame_size (bytes) to indicate the max allowed size for frame.

Control each encoded frame size into target limitation size by adjusting
whole frame's average QP value. The driver will use multi passes to
adjust average QP setp by step to achieve the target, and the result
may not strictly guaranteed. Frame size may exceed target alone with
using the maximum average QP value. The failure always happens on the
intra(especially the first intra frame of a new GOP) frames or set
max_frame_size with a very small number.

example cmdline:
    ffmpeg -hwaccel vaapi -vaapi_device /dev/dri/renderD128 -f rawvideo \
        -v verbose -s:v 352x288 -i ./input.yuv -vf format=nv12,hwupload \
        -c:v h264_vaapi -profile:v main -g 30 -rc_mode VBR -b:v 500k   \
        -bf 3 -max_frame_size 40000 -vframes 100 -y ./max_frame_size.h264

Max frame size was enabled since VA-API version (0, 33, 0), but query
is available since (1, 5, 0). It will be passed as a parameter in picParam
and should be set for each frame.

Signed-off-by: Linjie Fu <linjie.fu@intel.com>
Signed-off-by: Fei Wang <fei.w.wang@intel.com>

0 files changed, 0 insertions, 0 deletions