[FFmpeg-devel] lavc/vaapi_encode_h265: respect "slices" option in h265 vaapi encoder

[Mark Thompson]

On 02/08/17 06:57, Jun Zhao wrote:
> From 82eb7d1c3120081a7073cfb379802a28c769ae18 Mon Sep 17 00:00:00 2001
> From: Jun Zhao <jun.zhao at intel.com>
> Date: Tue, 1 Aug 2017 23:07:34 -0400
> Subject: [PATCH V2 4/4] lavc/vaapi_encode_h265: respect "slices" option in
>  h265 vaapi encoder
> 
> Enable multi-slice support in AVC/H.265 vaapi encoder.
> 
> Signed-off-by: Wang, Yi A <yi.a.wang at intel.com>
> Signed-off-by: Jun Zhao <jun.zhao at intel.com>
> ---
>  libavcodec/vaapi_encode_h265.c | 42 ++++++++++++++++++++++++++++++++++++------
>  1 file changed, 36 insertions(+), 6 deletions(-)
> 
> diff --git a/libavcodec/vaapi_encode_h265.c b/libavcodec/vaapi_encode_h265.c
> index cf6b9388d1..aa85331260 100644
> --- a/libavcodec/vaapi_encode_h265.c
> +++ b/libavcodec/vaapi_encode_h265.c
> @@ -176,6 +176,10 @@ typedef struct VAAPIEncodeH265Context {
>      unsigned int ctu_width;
>      unsigned int ctu_height;
>  
> +    int slice_of_ctus;
> +    int slice_mod_ctus;
> +    int last_ctu_index;
> +
>      int fixed_qp_idr;
>      int fixed_qp_p;
>      int fixed_qp_b;
> @@ -962,6 +966,7 @@ static int vaapi_encode_h265_init_picture_params(AVCodecContext *avctx,
>      VAEncPictureParameterBufferHEVC *vpic = pic->codec_picture_params;
>      VAAPIEncodeH265Context          *priv = ctx->priv_data;
>      int i;
> +    int max_slices;
>  
>      if (pic->type == PICTURE_TYPE_IDR) {
>          av_assert0(pic->display_order == pic->encode_order);
> @@ -1024,7 +1029,22 @@ static int vaapi_encode_h265_init_picture_params(AVCodecContext *avctx,
>          av_assert0(0 && "invalid picture type");
>      }
>  
> -    pic->nb_slices = 1;
> +    max_slices = 1;
> +    if (ctx->max_slices) {
> +        max_slices = FFMIN(priv->ctu_height, ctx->max_slices);
> +        if (avctx->slices > max_slices) {
> +            av_log(avctx, AV_LOG_WARNING, "The max slices number per frame "
> +                   "cannot more than %d.\n", max_slices);
> +        } else {
> +            max_slices = avctx->slices;
> +        }
> +    }
> +
> +    pic->nb_slices = max_slices;
> +
> +    priv->slice_of_ctus  = (priv->ctu_width * priv->ctu_height) / pic->nb_slices;
> +    priv->slice_mod_ctus = (priv->ctu_width * priv->ctu_height) % pic->nb_slices;
> +    priv->last_ctu_index = 0;
>  
>      return 0;
>  }
> @@ -1047,9 +1067,11 @@ static int vaapi_encode_h265_init_slice_params(AVCodecContext *avctx,
>      pslice = slice->priv_data;
>      mslice = &pslice->misc_slice_params;
>  
> -    // Currently we only support one slice per frame.
> -    vslice->slice_segment_address = 0;
> -    vslice->num_ctu_in_slice = priv->ctu_width * priv->ctu_height;
> +    vslice->slice_segment_address = priv->last_ctu_index;
> +    vslice->num_ctu_in_slice = priv->slice_of_ctus + (priv->slice_mod_ctus > 0 ? 1 : 0);
> +    if (priv->slice_mod_ctus > 0)
> +        priv->slice_mod_ctus--;
> +    priv->last_ctu_index += vslice->num_ctu_in_slice;
>  
>      switch (pic->type) {
>      case PICTURE_TYPE_IDR:
> @@ -1103,9 +1125,13 @@ static int vaapi_encode_h265_init_slice_params(AVCodecContext *avctx,
>      else
>          vslice->slice_qp_delta = priv->fixed_qp_idr - vpic->pic_init_qp;
>  
> -    vslice->slice_fields.bits.last_slice_of_pic_flag = 1;
> +    if (priv->last_ctu_index == priv->ctu_width * priv->ctu_height)
> +        vslice->slice_fields.bits.last_slice_of_pic_flag = 1;
>  
> -    mslice->first_slice_segment_in_pic_flag = 1;
> +    if (vslice->slice_segment_address == 0)
> +        mslice->first_slice_segment_in_pic_flag = 1;
> +    else
> +        mslice->first_slice_segment_in_pic_flag = 0;
>  
>      if (pic->type == PICTURE_TYPE_IDR) {
>          // No reference pictures.
> @@ -1198,6 +1224,10 @@ static av_cold int vaapi_encode_h265_configure(AVCodecContext *avctx)
>          av_assert0(0 && "Invalid RC mode.");
>      }
>  
> +    if (!ctx->max_slices && avctx->slices > 0)
> +        av_log(avctx, AV_LOG_WARNING, "The encode slice option is not "
> +               "supported with this VAAPI version.\n");
> +
>      return 0;
>  }
>  
> -- 
> 2.11.0
> 

All the same comments as the H.264 patch.

Also, you might want to consider whether you can/should set pps_loop_filter_across_slices_enabled_flag.  (And disable_deblocking_filter_idc in H.264, which I didn't think of there.)

- Mark