[libav-devel] [PATCH V2] lavc/qsvenc: set HRD buffer size

Zhong Li zhong.li at intel.com
Fri Dec 1 09:48:45 CET 2017


Hypothetical Reference Decoding (HRD) model assumes that data flows
into a buffer of the fixed size BufferSizeInKB with a constant bitrate.
Smaller BufferSizeInKB means smaller frame size variations,
but more difficult to maintain HRD.

Signed-off-by: Zhong Li <zhong.li at intel.com>
---
 libavcodec/qsvenc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libavcodec/qsvenc.c b/libavcodec/qsvenc.c
index 57f78c4..96c8fb5 100644
--- a/libavcodec/qsvenc.c
+++ b/libavcodec/qsvenc.c
@@ -495,6 +495,7 @@ static int init_video_param(AVCodecContext *avctx, QSVEncContext *q)
 #if QSV_HAVE_VCM
     case MFX_RATECONTROL_VCM:
 #endif
+        q->param.mfx.BufferSizeInKB   = avctx->rc_buffer_size / 8000;
         q->param.mfx.InitialDelayInKB = avctx->rc_initial_buffer_occupancy / 1000;
         q->param.mfx.TargetKbps       = avctx->bit_rate / 1000;
         q->param.mfx.MaxKbps          = avctx->rc_max_rate / 1000;
-- 
1.8.3.1



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