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

James Almer jamrial at gmail.com
Wed May 9 02:05:12 EEST 2018


On 5/8/2018 7:37 PM, Mark Thompson wrote:
> 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).

If you mean making it

    AVBufferRef *sps_ref[H264_MAX_SPS_COUNT];
    AVBufferRef *pps_ref[H264_MAX_PPS_COUNT];
    H264RawSPS *sps[H264_MAX_SPS_COUNT];
    H264RawPPS *pps[H264_MAX_PPS_COUNT];

Then sure, it indeed simplifies the patch a lot. Will send an updated
version in a moment.

> 
>>  
>>      // 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
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