[FFmpeg-devel] [PATCH v3] lavc/vaapi_encode: Enable block level bitrate control

[Xiang, Haihao]

On Vr, 2024-03-08 at 16:45 +0800, fei.w.wang-at-intel.com at ffmpeg.org wrote:
> From: Fei Wang <fei.w.wang at intel.com>
> 
> Signed-off-by: Fei Wang <fei.w.wang at intel.com>
> ---
>  doc/encoders.texi         |  4 ++++
>  libavcodec/vaapi_encode.c | 13 ++++++++++++-
>  libavcodec/vaapi_encode.h |  9 ++++++++-
>  3 files changed, 24 insertions(+), 2 deletions(-)
> 
> diff --git a/doc/encoders.texi b/doc/encoders.texi
> index 5f7864770e..7c223ed74c 100644
> --- a/doc/encoders.texi
> +++ b/doc/encoders.texi
> @@ -4089,6 +4089,10 @@ Quality-defined variable-bitrate.
>  Average variable bitrate.
>  @end table
>  
> + at item blbrc
> +Enable block level rate control, which assigns different bitrate block by
> block.
> +Invalid for CQP mode.
> +
>  @end table
>  
>  Each encoder also has its own specific options:
> diff --git a/libavcodec/vaapi_encode.c b/libavcodec/vaapi_encode.c
> index 808b79c0c7..940f0678a5 100644
> --- a/libavcodec/vaapi_encode.c
> +++ b/libavcodec/vaapi_encode.c
> @@ -1805,6 +1805,11 @@ static av_cold int
> vaapi_encode_init_rate_control(AVCodecContext *avctx)
>          int i, first = 1, res;
>  
>          supported_va_rc_modes = rc_attr.value;
> +        if (ctx->blbrc && !(supported_va_rc_modes & VA_RC_MB)) {
> +            ctx->blbrc = 0;
> +            av_log(avctx, AV_LOG_WARNING, "Driver does not support
> BLBRC.\n");
> +        }
> +
>          for (i = 0; i < FF_ARRAY_ELEMS(vaapi_encode_rc_modes); i++) {
>              rc_mode = &vaapi_encode_rc_modes[i];
>              if (supported_va_rc_modes & rc_mode->va_mode) {
> @@ -2016,13 +2021,18 @@ rc_mode_found:
>      ctx->va_bit_rate = rc_bits_per_second;
>  
>      av_log(avctx, AV_LOG_VERBOSE, "RC mode: %s.\n", rc_mode->name);
> +
> +    if (ctx->blbrc && ctx->va_rc_mode == VA_RC_CQP)
> +        ctx->blbrc = 0;
> +    av_log(avctx, AV_LOG_VERBOSE, "Block Level bitrate control: %s.\n", ctx-
> >blbrc ? "ON" : "OFF");
> +
>      if (rc_attr.value == VA_ATTRIB_NOT_SUPPORTED) {
>          // This driver does not want the RC mode attribute to be set.
>      } else {
>          ctx->config_attributes[ctx->nb_config_attributes++] =
>              (VAConfigAttrib) {
>              .type  = VAConfigAttribRateControl,
> -            .value = ctx->va_rc_mode,
> +            .value = ctx->blbrc ? ctx->va_rc_mode | VA_RC_MB : ctx-
> >va_rc_mode,
>          };
>      }
>  
> @@ -2051,6 +2061,7 @@ rc_mode_found:
>  #if VA_CHECK_VERSION(1, 1, 0)
>              .ICQ_quality_factor = av_clip(rc_quality, 1, 51),
>              .max_qp             = (avctx->qmax > 0 ? avctx->qmax : 0),
> +            .rc_flags.bits.mb_rate_control = ctx->blbrc ? 1 : 2,
>  #endif
>  #if VA_CHECK_VERSION(1, 3, 0)
>              .quality_factor     = rc_quality,
> diff --git a/libavcodec/vaapi_encode.h b/libavcodec/vaapi_encode.h
> index 6964055b93..0eed9691ca 100644
> --- a/libavcodec/vaapi_encode.h
> +++ b/libavcodec/vaapi_encode.h
> @@ -216,6 +216,9 @@ typedef struct VAAPIEncodeContext {
>      // available modes).
>      int             explicit_rc_mode;
>  
> +    // Block Level based bitrate control.
> +    int             blbrc;
> +
>      // Explicitly-set QP, for use with the "qp" options.
>      // (Forces CQP mode when set, overriding everything else.)
>      int             explicit_qp;
> @@ -538,7 +541,11 @@ int ff_vaapi_encode_close(AVCodecContext *avctx);
>      VAAPI_ENCODE_RC_MODE(VBR,  "Variable-bitrate"), \
>      VAAPI_ENCODE_RC_MODE(ICQ,  "Intelligent constant-quality"), \
>      VAAPI_ENCODE_RC_MODE(QVBR, "Quality-defined variable-bitrate"), \
> -    VAAPI_ENCODE_RC_MODE(AVBR, "Average variable-bitrate")
> +    VAAPI_ENCODE_RC_MODE(AVBR, "Average variable-bitrate"), \
> +    { "blbrc", \
> +      "Block level based bitrate control",\
> +      OFFSET(common.blbrc), AV_OPT_TYPE_BOOL, \
> +      { .i64 = 0 }, 0, 1, FLAGS }
>  
>  
>  #endif /* AVCODEC_VAAPI_ENCODE_H */

LGTM, I will push this patch if there is no objection.

Thanks
Haihao