[FFmpeg-devel] [PATCH V3 3/4] libavcodec/qsvenc: Add low latency P-pyramid support to qsv

[Xiang, Haihao]

On Thu, 2022-01-13 at 13:12 +0800, Wenbin Chen wrote:
> Add low latency P-pyramid support to qsv. This feature relates to
> command line option "-p_strategy". To enable this flag, user also
> need to set "-bf" to 0. P-strategy has two modes "1-simple" and
> "2-pyramid". The details of the two models refer to
> 
https://github.com/Intel-Media-SDK/MediaSDK/blob/master/doc/mediasdk-man.md#preftype
> 
> Signed-off-by: Wenbin Chen <wenbin.chen at intel.com>
> ---
>  doc/encoders.texi   |  6 ++++++
>  libavcodec/qsvenc.c | 36 ++++++++++++++++++++++++++++++++++++
>  libavcodec/qsvenc.h |  3 +++
>  3 files changed, 45 insertions(+)
> 
> diff --git a/doc/encoders.texi b/doc/encoders.texi
> index 6fc94daa11..3d7c944fba 100644
> --- a/doc/encoders.texi
> +++ b/doc/encoders.texi
> @@ -3296,6 +3296,9 @@ to allow changing of frame type from P and B to I.
>  @item @var{adaptive_b}
>  This flag controls changing of frame type from B to P.
>  
> + at item @var{p_strategy}
> +Enable P-pyramid: 0-default 1-simple 2-pyramid(bf need to be set to 0).
> +
>  @item @var{b_strategy}
>  This option controls usage of B frames as reference.
>  
> @@ -3394,6 +3397,9 @@ Enable rate distortion optimization.
>  @item @var{max_frame_size}
>  Maximum encoded frame size in bytes.
>  
> + at item @var{p_strategy}
> +Enable P-pyramid: 0-default 1-simple 2-pyramid(bf need to be set to 0).
> +
>  @item @var{dblk_idc}
>  This option disable deblocking. It has value in range 0~2.
>  
> diff --git a/libavcodec/qsvenc.c b/libavcodec/qsvenc.c
> index e87b69369a..f2ba0241c6 100644
> --- a/libavcodec/qsvenc.c
> +++ b/libavcodec/qsvenc.c
> @@ -315,6 +315,14 @@ static void dump_video_param(AVCodecContext *avctx,
> QSVEncContext *q,
>      case MFX_B_REF_PYRAMID: av_log(avctx, AV_LOG_VERBOSE,
> "pyramid");   break;
>      default:                av_log(avctx, AV_LOG_VERBOSE,
> "auto");      break;
>      }
> +
> +    av_log(avctx, AV_LOG_VERBOSE, "; PRefType: ");
> +    switch (co3->PRefType) {
> +    case MFX_P_REF_DEFAULT: av_log(avctx, AV_LOG_VERBOSE,
> "default");   break;
> +    case MFX_P_REF_SIMPLE:  av_log(avctx, AV_LOG_VERBOSE,
> "simple");    break;
> +    case MFX_P_REF_PYRAMID: av_log(avctx, AV_LOG_VERBOSE,
> "pyramid");   break;
> +    default:                av_log(avctx, AV_LOG_VERBOSE,
> "unknown");   break;
> +    }
>      av_log(avctx, AV_LOG_VERBOSE, "\n");
>  #endif
>  
> @@ -934,6 +942,34 @@ static int init_video_param(AVCodecContext *avctx,
> QSVEncContext *q)
>  #if QSV_HAVE_CO3
>          q->extco3.Header.BufferId      = MFX_EXTBUFF_CODING_OPTION3;
>          q->extco3.Header.BufferSz      = sizeof(q->extco3);
> +
> +        if (avctx->codec_id == AV_CODEC_ID_HEVC ||
> +            avctx->codec_id == AV_CODEC_ID_H264) {
> +#if QSV_HAVE_PREF
> +            switch (q->p_strategy) {
> +            case 0:
> +                q->extco3.PRefType = MFX_P_REF_DEFAULT;
> +                break;
> +            case 1:
> +                q->extco3.PRefType = MFX_P_REF_SIMPLE;
> +                break;
> +            case 2:
> +                q->extco3.PRefType = MFX_P_REF_PYRAMID;
> +                break;
> +            default:
> +                q->extco3.PRefType = MFX_P_REF_DEFAULT;
> +                av_log(avctx, AV_LOG_WARNING,
> +                       "invalid p_strategy, set to default\n");
> +                break;
> +            }
> +            if (q->extco3.PRefType == MFX_P_REF_PYRAMID &&
> +                avctx->max_b_frames != 0) {
> +                av_log(avctx, AV_LOG_WARNING,
> +                       "Please set max_b_frames(-bf) to 0 to enable P-
> pyramid\n");
> +            }
> +#endif
> +        }
> +
>  #if QSV_HAVE_GPB
>          if (avctx->codec_id == AV_CODEC_ID_HEVC)
>              q->extco3.GPB              = q->gpb ? MFX_CODINGOPTION_ON :
> MFX_CODINGOPTION_OFF;
> diff --git a/libavcodec/qsvenc.h b/libavcodec/qsvenc.h
> index aa49b35f07..960604cb9a 100644
> --- a/libavcodec/qsvenc.h
> +++ b/libavcodec/qsvenc.h
> @@ -51,6 +51,7 @@
>  #define QSV_HAVE_LA_DS  QSV_VERSION_ATLEAST(1, 8)
>  #define QSV_HAVE_LA_HRD QSV_VERSION_ATLEAST(1, 11)
>  #define QSV_HAVE_VDENC  QSV_VERSION_ATLEAST(1, 15)
> +#define QSV_HAVE_PREF   QSV_VERSION_ATLEAST(1, 16)
>  
>  #define QSV_HAVE_GPB    QSV_VERSION_ATLEAST(1, 18)
>  
> @@ -95,6 +96,7 @@
>  { "extbrc",         "Extended bitrate
> control",               OFFSET(qsv.extbrc),         AV_OPT_TYPE_INT, { .i64 =
> -1 }, -1,          1, VE },                         \
>  { "adaptive_i",     "Adaptive I-frame
> placement",             OFFSET(qsv.adaptive_i),     AV_OPT_TYPE_INT, { .i64 =
> -1 }, -1,          1, VE },                         \
>  { "adaptive_b",     "Adaptive B-frame
> placement",             OFFSET(qsv.adaptive_b),     AV_OPT_TYPE_INT, { .i64 =
> -1 }, -1,          1, VE },                         \
> +{ "p_strategy",     "Enable P-pyramid: 0-default 1-simple 2-pyramid(bf need
> to be set to 0).",    OFFSET(qsv.p_strategy), AV_OPT_TYPE_INT,    { .i64 = 0},
> 0,    2, VE },                         \
>  { "b_strategy",     "Strategy to choose between I/P/B-frames",
> OFFSET(qsv.b_strategy),    AV_OPT_TYPE_INT, { .i64 = -1 }, -1,          1, VE
> },                         \
>  { "forced_idr",     "Forcing I frames as IDR
> frames",         OFFSET(qsv.forced_idr),     AV_OPT_TYPE_BOOL,{ .i64 =
> 0  },  0,          1, VE },                         \
>  { "low_power", "enable low power mode(experimental: many limitations by mfx
> version, BRC modes, etc.)", OFFSET(qsv.low_power), AV_OPT_TYPE_BOOL, { .i64 =
> -1}, -1, 1, VE},\
> @@ -187,6 +189,7 @@ typedef struct QSVEncContext {
>      int adaptive_i;
>      int adaptive_b;
>      int b_strategy;
> +    int p_strategy;
>      int cavlc;
>  
>      int int_ref_type;

LGTM

-Haihao