[FFmpeg-devel] [PATCH v1] lavc/vaapi_encode: Enable Macroblock based bitrate control

[Xiang, Haihao]

On Wo, 2024-02-07 at 08:40 +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         |  3 +++
>  libavcodec/vaapi_encode.c | 11 ++++++++++-
>  libavcodec/vaapi_encode.h |  9 ++++++++-
>  3 files changed, 21 insertions(+), 2 deletions(-)
> 
> diff --git a/doc/encoders.texi b/doc/encoders.texi
> index c9fe6d6143..b66d5da31f 100644
> --- a/doc/encoders.texi
> +++ b/doc/encoders.texi
> @@ -4080,6 +4080,9 @@ Quality-defined variable-bitrate.
>  Average variable bitrate.
>  @end table
>  
> + at item mbbrc
> +Enable Macroblock based rate control. 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 86f4110cd2..83eb881428 100644
> --- a/libavcodec/vaapi_encode.c
> +++ b/libavcodec/vaapi_encode.c
> @@ -1806,6 +1806,9 @@ 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->mbbrc && !(supported_va_rc_modes & VA_RC_MB))
> +            ctx->mbbrc = 0;
> +
>          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) {
> @@ -2017,13 +2020,18 @@ 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->mbbrc && ctx->va_rc_mode == VA_RC_CQP)
> +        ctx->mbbrc = 0;
> +    av_log(avctx, AV_LOG_VERBOSE, "MB bitrate control: %d.\n", ctx->mbbrc);

Better to use a string representation of the boolean value, E.g. on/off, or
enabled/disabled.

Thanks
Haihao

> +
>      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->mbbrc ? ctx->va_rc_mode | VA_RC_MB : ctx-
> >va_rc_mode,
>          };
>      }
>  
> @@ -2052,6 +2060,7 @@ 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->mbbrc ? 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 d5d6d5eb1b..f2abfed459 100644
> --- a/libavcodec/vaapi_encode.h
> +++ b/libavcodec/vaapi_encode.h
> @@ -216,6 +216,9 @@ typedef struct VAAPIEncodeContext {
>      // available modes).
>      int             explicit_rc_mode;
>  
> +    // Macroblock based rate control.
> +    int             mbbrc;
> +
>      // 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"), \
> +    { "mbbrc", \
> +      "Macroblock based bitrate control",\
> +      OFFSET(common.mbbrc), AV_OPT_TYPE_BOOL, \
> +      { .i64 = 0 }, 0, 1, FLAGS }
>  
>  
>  #endif /* AVCODEC_VAAPI_ENCODE_H */