On 31/10/17 02:37, Jun Zhao wrote:
> From 7eef9be1c8a92bf625d62a0f97f762f1342c6d78 Mon Sep 17 00:00:00 2001
> From: Jun Zhao <jun.z...@intel.com>
> Date: Tue, 31 Oct 2017 10:13:42 +0800
> Subject: [PATCH 1/2] lavc/vaapi_encode: correct the HRD buffer size calculate.
>
> when rc_buffer_size didn't setting, always use the max bit rate
> per second as HRD buffer size.
>
> Signed-off-by: Jun Zhao <jun.z...@intel.com>
> Signed-off-by: Wang, Yi A <yi.a.w...@intel.com>
> ---
> libavcodec/vaapi_encode.c | 21 ++++++++++-----------
> 1 file changed, 10 insertions(+), 11 deletions(-)
>
> diff --git a/libavcodec/vaapi_encode.c b/libavcodec/vaapi_encode.c
> index 590f4be4ed..d5f89ef346 100644
> --- a/libavcodec/vaapi_encode.c
> +++ b/libavcodec/vaapi_encode.c
> @@ -1144,19 +1144,9 @@ static av_cold int
> vaapi_encode_init_rate_control(AVCodecContext *avctx)
> return AVERROR(EINVAL);
> }
>
> - if (avctx->rc_buffer_size)
> - hrd_buffer_size = avctx->rc_buffer_size;
> - else
> - hrd_buffer_size = avctx->bit_rate;
> - if (avctx->rc_initial_buffer_occupancy)
> - hrd_initial_buffer_fullness = avctx->rc_initial_buffer_occupancy;
> - else
> - hrd_initial_buffer_fullness = hrd_buffer_size * 3 / 4;
> -
> if (ctx->va_rc_mode == VA_RC_CBR) {
> rc_bits_per_second = avctx->bit_rate;
> rc_target_percentage = 100;
> - rc_window_size = 1000;
> } else {
> if (avctx->rc_max_rate < avctx->bit_rate) {
> // Max rate is unset or invalid, just use the normal bitrate.
> @@ -1166,8 +1156,17 @@ static av_cold int
> vaapi_encode_init_rate_control(AVCodecContext *avctx)
> rc_bits_per_second = avctx->rc_max_rate;
> rc_target_percentage = (avctx->bit_rate * 100) /
> rc_bits_per_second;
> }
> - rc_window_size = (hrd_buffer_size * 1000) / avctx->bit_rate;
> }
> + rc_window_size = (rc_bits_per_second * 1000) / avctx->bit_rate;
> +
> + if (avctx->rc_buffer_size)
> + hrd_buffer_size = avctx->rc_buffer_size;
> + else
> + hrd_buffer_size = rc_bits_per_second;
> + if (avctx->rc_initial_buffer_occupancy)
> + hrd_initial_buffer_fullness = avctx->rc_initial_buffer_occupancy;
> + else
> + hrd_initial_buffer_fullness = hrd_buffer_size * 3 / 4;
>
> ctx->rc_params.misc.type = VAEncMiscParameterTypeRateControl;
> ctx->rc_params.rc = (VAEncMiscParameterRateControl) {
> --
> 2.14.1
>
Why? If the RC buffer size is unset it currently guesses one second of the
target bitrate - in what way is the peak bitrate any more appropriate as a
guess?
- Mark
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
