PR #20424 opened by cgutman URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20424 Patch URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20424.patch
AVBR does not use `VAEncMiscParameterTypeHRD` (see [line 1212](https://code.ffmpeg.org/FFmpeg/FFmpeg/src/commit/858aa6176b5320e8f648461194a80cfda766de5a/libavcodec/vaapi_encode.c#L1212)), so attempting to set `rc_buffer_size and bit_rate together will cause the `rc_buffer_size` to be ignored if the VAAPI driver supports AVBR. We should prefer regular VBR for that case. >From 56b2e59e8da1d316a430c7ec0deeb55c7ea3c86a Mon Sep 17 00:00:00 2001 From: Cameron Gutman <[email protected]> Date: Tue, 1 Apr 2025 23:11:20 -0500 Subject: [PATCH] avcodec/vaapi_encode: skip AVBR if HRD parameters are set AVBR does not use VAEncMiscParameterTypeHRD, so attempting to set rc_buffer_size and bit_rate together will cause the rc_buffer_size to be ignored if the VAAPI driver supports AVBR. We should prefer regular VBR for that case. Signed-off-by: Cameron Gutman <[email protected]> --- libavcodec/vaapi_encode.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/libavcodec/vaapi_encode.c b/libavcodec/vaapi_encode.c index 8960e6b20a..8bd0701caf 100644 --- a/libavcodec/vaapi_encode.c +++ b/libavcodec/vaapi_encode.c @@ -1338,7 +1338,10 @@ static av_cold int vaapi_encode_init_rate_control(AVCodecContext *avctx) TRY_RC_MODE(RC_MODE_CBR, 0); if (avctx->bit_rate > 0) { - TRY_RC_MODE(RC_MODE_AVBR, 0); + // AVBR does not enforce RC buffer constraints + if (!avctx->rc_buffer_size && !avctx->rc_initial_buffer_occupancy) + TRY_RC_MODE(RC_MODE_AVBR, 0); + TRY_RC_MODE(RC_MODE_VBR, 0); TRY_RC_MODE(RC_MODE_CBR, 0); } else { -- 2.49.1 _______________________________________________ ffmpeg-devel mailing list -- [email protected] To unsubscribe send an email to [email protected]
