[FFmpeg-devel] [PATCH 2/2] avcodec/cbs_h2645: use AVBufferRef to store list of active parameter sets

Mark Thompson sw at jkqxz.net
Wed May 9 01:37:50 EEST 2018


On 08/05/18 21:48, James Almer wrote:
> This is more in line to how h264_ps handles it.
> 
> Signed-off-by: James Almer <jamrial at gmail.com>
> ---
> Not really going to make much of a difference seeing parameter sets
> rarely show up in-band even in raw streams, but it's one less memcpy
> anyway.
> 
>  libavcodec/cbs_h264.h                 |  4 +--
>  libavcodec/cbs_h2645.c                | 41 ++++++++++++++-------------
>  libavcodec/cbs_h264_syntax_template.c | 19 ++++++-------
>  libavcodec/cbs_h265.h                 |  6 ++--
>  libavcodec/cbs_h265_syntax_template.c | 21 +++++++-------
>  5 files changed, 44 insertions(+), 47 deletions(-)
> 
> diff --git a/libavcodec/cbs_h264.h b/libavcodec/cbs_h264.h
> index becea3adfe..239f3b6b90 100644
> --- a/libavcodec/cbs_h264.h
> +++ b/libavcodec/cbs_h264.h
> @@ -420,8 +420,8 @@ typedef struct CodedBitstreamH264Context {
>  
>      // All currently available parameter sets.  These are updated when
>      // any parameter set NAL unit is read/written with this context.
> -    H264RawSPS *sps[H264_MAX_SPS_COUNT];
> -    H264RawPPS *pps[H264_MAX_PPS_COUNT];
> +    AVBufferRef *sps[H264_MAX_SPS_COUNT];
> +    AVBufferRef *pps[H264_MAX_PPS_COUNT];

Can we keep the current xps variables as they are and add a separate xps_ref?  That doesn't significantly increase the complexity of the replacement functions, and would avoid the ugly casting in the read/write templated code (indeed, I think it removes all changes there entirely).

>  
>      // The currently active parameter sets.  These are updated when any
>      // NAL unit refers to the relevant parameter set.  These pointers
> diff --git a/libavcodec/cbs_h2645.c b/libavcodec/cbs_h2645.c
> index 580ca09f63..6c81a2e1b3 100644
> --- a/libavcodec/cbs_h2645.c
> +++ b/libavcodec/cbs_h2645.c
> @@ -676,22 +676,23 @@ static int cbs_h2645_split_fragment(CodedBitstreamContext *ctx,
>  
>  #define cbs_h2645_replace_ps(h26n, ps_name, ps_var, id_element) \
>  static int cbs_h26 ## h26n ## _replace_ ## ps_var(CodedBitstreamContext *ctx, \
> -                                                  const H26 ## h26n ## Raw ## ps_name *ps_var)  \
> +                                                  CodedBitstreamUnit *unit)  \
>  { \
>      CodedBitstreamH26 ## h26n ## Context *priv = ctx->priv_data; \
> +    H26 ## h26n ## Raw ## ps_name *ps_var = unit->content; \
>      unsigned int id = ps_var->id_element; \
>      if (id > FF_ARRAY_ELEMS(priv->ps_var)) { \
>          av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid " #ps_name \
>                 " id : %d.\n", id); \
>          return AVERROR_INVALIDDATA; \
>      } \
> -    if (priv->ps_var[id] == priv->active_ ## ps_var) \
> +    if (priv->ps_var[id] && \
> +        (H26 ## h26n ## Raw ## ps_name *) priv->ps_var[id]->data == priv->active_ ## ps_var) \
>          priv->active_ ## ps_var = NULL ; \
> -    av_freep(&priv->ps_var[id]); \
> -    priv->ps_var[id] = av_malloc(sizeof(*ps_var)); \
> +    av_buffer_unref(&priv->ps_var[id]); \
> +    priv->ps_var[id] = av_buffer_ref(unit->content_ref); \
>      if (!priv->ps_var[id]) \
>          return AVERROR(ENOMEM); \
> -    memcpy(priv->ps_var[id], ps_var, sizeof(*ps_var)); \
>      return 0; \
>  }
>  
> @@ -725,7 +726,7 @@ static int cbs_h264_read_nal_unit(CodedBitstreamContext *ctx,
>              if (err < 0)
>                  return err;
>  
> -            err = cbs_h264_replace_sps(ctx, sps);
> +            err = cbs_h264_replace_sps(ctx, unit);
>              if (err < 0)
>                  return err;
>          }
> @@ -759,7 +760,7 @@ static int cbs_h264_read_nal_unit(CodedBitstreamContext *ctx,
>              if (err < 0)
>                  return err;
>  
> -            err = cbs_h264_replace_pps(ctx, pps);
> +            err = cbs_h264_replace_pps(ctx, unit);
>              if (err < 0)
>                  return err;
>          }
> @@ -872,7 +873,7 @@ static int cbs_h265_read_nal_unit(CodedBitstreamContext *ctx,
>              if (err < 0)
>                  return err;
>  
> -            err = cbs_h265_replace_vps(ctx, vps);
> +            err = cbs_h265_replace_vps(ctx, unit);
>              if (err < 0)
>                  return err;
>          }
> @@ -891,7 +892,7 @@ static int cbs_h265_read_nal_unit(CodedBitstreamContext *ctx,
>              if (err < 0)
>                  return err;
>  
> -            err = cbs_h265_replace_sps(ctx, sps);
> +            err = cbs_h265_replace_sps(ctx, unit);
>              if (err < 0)
>                  return err;
>          }
> @@ -911,7 +912,7 @@ static int cbs_h265_read_nal_unit(CodedBitstreamContext *ctx,
>              if (err < 0)
>                  return err;
>  
> -            err = cbs_h265_replace_pps(ctx, pps);
> +            err = cbs_h265_replace_pps(ctx, unit);
>              if (err < 0)
>                  return err;
>          }
> @@ -1001,7 +1002,7 @@ static int cbs_h264_write_nal_unit(CodedBitstreamContext *ctx,
>              if (err < 0)
>                  return err;
>  
> -            err = cbs_h264_replace_sps(ctx, sps);
> +            err = cbs_h264_replace_sps(ctx, unit);
>              if (err < 0)
>                  return err;
>          }
> @@ -1025,7 +1026,7 @@ static int cbs_h264_write_nal_unit(CodedBitstreamContext *ctx,
>              if (err < 0)
>                  return err;
>  
> -            err = cbs_h264_replace_pps(ctx, pps);
> +            err = cbs_h264_replace_pps(ctx, unit);
>              if (err < 0)
>                  return err;
>          }
> @@ -1122,7 +1123,7 @@ static int cbs_h265_write_nal_unit(CodedBitstreamContext *ctx,
>              if (err < 0)
>                  return err;
>  
> -            err = cbs_h265_replace_vps(ctx, vps);
> +            err = cbs_h265_replace_vps(ctx, unit);
>              if (err < 0)
>                  return err;
>          }
> @@ -1136,7 +1137,7 @@ static int cbs_h265_write_nal_unit(CodedBitstreamContext *ctx,
>              if (err < 0)
>                  return err;
>  
> -            err = cbs_h265_replace_sps(ctx, sps);
> +            err = cbs_h265_replace_sps(ctx, unit);
>              if (err < 0)
>                  return err;
>          }
> @@ -1150,7 +1151,7 @@ static int cbs_h265_write_nal_unit(CodedBitstreamContext *ctx,
>              if (err < 0)
>                  return err;
>  
> -            err = cbs_h265_replace_pps(ctx, pps);
> +            err = cbs_h265_replace_pps(ctx, unit);
>              if (err < 0)
>                  return err;
>          }
> @@ -1384,9 +1385,9 @@ static void cbs_h264_close(CodedBitstreamContext *ctx)
>      av_freep(&h264->common.write_buffer);
>  
>      for (i = 0; i < FF_ARRAY_ELEMS(h264->sps); i++)
> -        av_freep(&h264->sps[i]);
> +        av_buffer_unref(&h264->sps[i]);
>      for (i = 0; i < FF_ARRAY_ELEMS(h264->pps); i++)
> -        av_freep(&h264->pps[i]);
> +        av_buffer_unref(&h264->pps[i]);
>  }
>  
>  static void cbs_h265_close(CodedBitstreamContext *ctx)
> @@ -1399,11 +1400,11 @@ static void cbs_h265_close(CodedBitstreamContext *ctx)
>      av_freep(&h265->common.write_buffer);
>  
>      for (i = 0; i < FF_ARRAY_ELEMS(h265->vps); i++)
> -        av_freep(&h265->vps[i]);
> +        av_buffer_unref(&h265->vps[i]);
>      for (i = 0; i < FF_ARRAY_ELEMS(h265->sps); i++)
> -        av_freep(&h265->sps[i]);
> +        av_buffer_unref(&h265->sps[i]);
>      for (i = 0; i < FF_ARRAY_ELEMS(h265->pps); i++)
> -        av_freep(&h265->pps[i]);
> +        av_buffer_unref(&h265->pps[i]);
>  }
>  
>  const CodedBitstreamType ff_cbs_type_h264 = {
> diff --git a/libavcodec/cbs_h264_syntax_template.c b/libavcodec/cbs_h264_syntax_template.c
> index c3327f6e90..6e4155baac 100644
> --- a/libavcodec/cbs_h264_syntax_template.c
> +++ b/libavcodec/cbs_h264_syntax_template.c
> @@ -368,7 +368,7 @@ static int FUNC(pps)(CodedBitstreamContext *ctx, RWContext *rw,
>      ue(pic_parameter_set_id, 0, 255);
>      ue(seq_parameter_set_id, 0, 31);
>  
> -    sps = h264->sps[current->seq_parameter_set_id];
> +    sps = (const H264RawSPS *)h264->sps[current->seq_parameter_set_id]->data;
>      if (!sps) {
>          av_log(ctx->log_ctx, AV_LOG_ERROR, "SPS id %d not available.\n",
>                 current->seq_parameter_set_id);
> @@ -471,13 +471,12 @@ static int FUNC(sei_buffering_period)(CodedBitstreamContext *ctx, RWContext *rw,
>  
>      ue(seq_parameter_set_id, 0, 31);
>  
> -    sps = h264->sps[current->seq_parameter_set_id];
> -    if (!sps) {
> +    if (!h264->sps[current->seq_parameter_set_id]) {
>          av_log(ctx->log_ctx, AV_LOG_ERROR, "SPS id %d not available.\n",
>                 current->seq_parameter_set_id);
>          return AVERROR_INVALIDDATA;
>      }
> -    h264->active_sps = sps;
> +    h264->active_sps = sps = (const H264RawSPS *)h264->sps[current->seq_parameter_set_id]->data;
>  
>      if (sps->vui.nal_hrd_parameters_present_flag) {
>          for (i = 0; i <= sps->vui.nal_hrd_parameters.cpb_cnt_minus1; i++) {
> @@ -578,7 +577,7 @@ static int FUNC(sei_pic_timing)(CodedBitstreamContext *ctx, RWContext *rw,
>              }
>          }
>          if (k >= 0)
> -            sps = h264->sps[k];
> +            sps = (const H264RawSPS *)h264->sps[k]->data;
>      }
>      if (!sps) {
>          av_log(ctx->log_ctx, AV_LOG_ERROR,
> @@ -1100,21 +1099,19 @@ static int FUNC(slice_header)(CodedBitstreamContext *ctx, RWContext *rw,
>  
>      ue(pic_parameter_set_id, 0, 255);
>  
> -    pps = h264->pps[current->pic_parameter_set_id];
> -    if (!pps) {
> +    if (!h264->pps[current->pic_parameter_set_id]) {
>          av_log(ctx->log_ctx, AV_LOG_ERROR, "PPS id %d not available.\n",
>                 current->pic_parameter_set_id);
>          return AVERROR_INVALIDDATA;
>      }
> -    h264->active_pps = pps;
> +    h264->active_pps = pps = (const H264RawPPS *)h264->pps[current->pic_parameter_set_id]->data;
>  
> -    sps = h264->sps[pps->seq_parameter_set_id];
> -    if (!sps) {
> +    if (!h264->sps[pps->seq_parameter_set_id]) {
>          av_log(ctx->log_ctx, AV_LOG_ERROR, "SPS id %d not available.\n",
>                 pps->seq_parameter_set_id);
>          return AVERROR_INVALIDDATA;
>      }
> -    h264->active_sps = sps;
> +    h264->active_sps = sps = (const H264RawSPS *)h264->sps[pps->seq_parameter_set_id]->data;
>  
>      if (sps->separate_colour_plane_flag)
>          u(2, colour_plane_id, 0, 2);
> diff --git a/libavcodec/cbs_h265.h b/libavcodec/cbs_h265.h
> index 1b357293ab..4eec99e9a8 100644
> --- a/libavcodec/cbs_h265.h
> +++ b/libavcodec/cbs_h265.h
> @@ -522,9 +522,9 @@ typedef struct CodedBitstreamH265Context {
>  
>      // All currently available parameter sets.  These are updated when
>      // any parameter set NAL unit is read/written with this context.
> -    H265RawVPS *vps[HEVC_MAX_VPS_COUNT];
> -    H265RawSPS *sps[HEVC_MAX_SPS_COUNT];
> -    H265RawPPS *pps[HEVC_MAX_PPS_COUNT];
> +    AVBufferRef *vps[HEVC_MAX_VPS_COUNT];
> +    AVBufferRef *sps[HEVC_MAX_SPS_COUNT];
> +    AVBufferRef *pps[HEVC_MAX_PPS_COUNT];
>  
>      // The currently active parameter sets.  These are updated when any
>      // NAL unit refers to the relevant parameter set.  These pointers
> diff --git a/libavcodec/cbs_h265_syntax_template.c b/libavcodec/cbs_h265_syntax_template.c
> index 9f13061f38..bc9e6ddf08 100644
> --- a/libavcodec/cbs_h265_syntax_template.c
> +++ b/libavcodec/cbs_h265_syntax_template.c
> @@ -690,11 +690,12 @@ static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
>      CHECK(FUNC(nal_unit_header)(ctx, rw, &current->nal_unit_header, HEVC_NAL_SPS));
>  
>      u(4, sps_video_parameter_set_id, 0, 15);
> -    h265->active_vps = vps = h265->vps[current->sps_video_parameter_set_id];
> +    h265->active_vps = vps = NULL;
>  
>      u(3, sps_max_sub_layers_minus1, 0, HEVC_MAX_SUB_LAYERS - 1);
>      flag(sps_temporal_id_nesting_flag);
> -    if (vps) {
> +    if (h265->vps[current->sps_video_parameter_set_id]) {
> +        h265->active_vps = vps = (const H265RawVPS *)h265->vps[current->sps_video_parameter_set_id]->data;
>          if (vps->vps_max_sub_layers_minus1 > current->sps_max_sub_layers_minus1) {
>              av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid stream: "
>                     "sps_max_sub_layers_minus1 (%d) must be less than or equal to "
> @@ -949,13 +950,13 @@ static int FUNC(pps)(CodedBitstreamContext *ctx, RWContext *rw,
>  
>      ue(pps_pic_parameter_set_id, 0, 63);
>      ue(pps_seq_parameter_set_id, 0, 15);
> -    sps = h265->sps[current->pps_seq_parameter_set_id];
> -    if (!sps) {
> +
> +    if (!h265->sps[current->pps_seq_parameter_set_id]) {
>          av_log(ctx->log_ctx, AV_LOG_ERROR, "SPS id %d not available.\n",
>                 current->pps_seq_parameter_set_id);
>          return AVERROR_INVALIDDATA;
>      }
> -    h265->active_sps = sps;
> +    h265->active_sps = sps = (const H265RawSPS *)h265->sps[current->pps_seq_parameter_set_id]->data;
>  
>      flag(dependent_slice_segments_enabled_flag);
>      flag(output_flag_present_flag);
> @@ -1224,21 +1225,19 @@ static int FUNC(slice_segment_header)(CodedBitstreamContext *ctx, RWContext *rw,
>  
>      ue(slice_pic_parameter_set_id, 0, 63);
>  
> -    pps = h265->pps[current->slice_pic_parameter_set_id];
> -    if (!pps) {
> +    if (!h265->pps[current->slice_pic_parameter_set_id]) {
>          av_log(ctx->log_ctx, AV_LOG_ERROR, "PPS id %d not available.\n",
>                 current->slice_pic_parameter_set_id);
>          return AVERROR_INVALIDDATA;
>      }
> -    h265->active_pps = pps;
> +    h265->active_pps = pps = (const H265RawPPS *)h265->pps[current->slice_pic_parameter_set_id]->data;
>  
> -    sps = h265->sps[pps->pps_seq_parameter_set_id];
> -    if (!sps) {
> +    if (!h265->sps[pps->pps_seq_parameter_set_id]) {
>          av_log(ctx->log_ctx, AV_LOG_ERROR, "SPS id %d not available.\n",
>                 pps->pps_seq_parameter_set_id);
>          return AVERROR_INVALIDDATA;
>      }
> -    h265->active_sps = sps;
> +    h265->active_sps = sps = (const H265RawSPS *)h265->sps[pps->pps_seq_parameter_set_id]->data;
>  
>      min_cb_log2_size_y = sps->log2_min_luma_coding_block_size_minus3 + 3;
>      ctb_log2_size_y = min_cb_log2_size_y + sps->log2_diff_max_min_luma_coding_block_size;
> 

Good change.  (I'm realising now that it fixes the possible dangling references held in pointers in the stored parameter sets too, which I hadn't thought about before.)

Thanks,

- Mark


More information about the ffmpeg-devel mailing list