[FFmpeg-devel] [PATCH] mp4: Support writing declarative SEis to hvcC

[James Almer]

On 8/17/2017 8:54 AM, Vittorio Giovara wrote:
> Signed-off-by: Vittorio Giovara <vittorio.giovara at gmail.com>
> ---
> Right now only one SEI type is added, there could be more declarative
> ones, but I'm not sure how to properly identify them.

Content Light Level probably, judging by the fact Mastering Display is one.

> Also, the way to check for the seiPayloadType could be improved,
> suggestions are welcome.
> Vittorio
> 
>  libavcodec/extract_extradata_bsf.c |  1 +
>  libavformat/hevc.c                 | 28 ++++++++++++++++++++--------
>  2 files changed, 21 insertions(+), 8 deletions(-)
> 
> diff --git a/libavcodec/extract_extradata_bsf.c b/libavcodec/extract_extradata_bsf.c
> index 4cd0ca1137..e0d8aa99b5 100644
> --- a/libavcodec/extract_extradata_bsf.c
> +++ b/libavcodec/extract_extradata_bsf.c
> @@ -54,6 +54,7 @@ static int extract_extradata_h2645(AVBSFContext *ctx, AVPacket *pkt,
>  {
>      static const int extradata_nal_types_hevc[] = {
>          HEVC_NAL_VPS, HEVC_NAL_SPS, HEVC_NAL_PPS,
> +        HEVC_NAL_SEI_PREFIX, HEVC_NAL_SEI_SUFFIX,
>      };
>      static const int extradata_nal_types_h264[] = {
>          H264_NAL_SPS, H264_NAL_PPS,
> diff --git a/libavformat/hevc.c b/libavformat/hevc.c
> index 1a2d6cdd2b..9ff2b858dd 100644
> --- a/libavformat/hevc.c
> +++ b/libavformat/hevc.c
> @@ -22,6 +22,7 @@
>  #include "libavcodec/get_bits.h"
>  #include "libavcodec/golomb.h"
>  #include "libavcodec/hevc.h"
> +#include "libavcodec/hevc_sei.h"
>  #include "libavutil/intreadwrite.h"
>  #include "avc.h"
>  #include "avio.h"
> @@ -763,17 +764,10 @@ static int hvcc_add_nal_unit(uint8_t *nal_buf, uint32_t nal_size,
>  
>      nal_unit_parse_header(&gbc, &nal_type);
>  
> -    /*
> -     * Note: only 'declarative' SEI messages are allowed in
> -     * hvcC. Perhaps the SEI playload type should be checked
> -     * and non-declarative SEI messages discarded?
> -     */
>      switch (nal_type) {
>      case HEVC_NAL_VPS:
>      case HEVC_NAL_SPS:
>      case HEVC_NAL_PPS:
> -    case HEVC_NAL_SEI_PREFIX:
> -    case HEVC_NAL_SEI_SUFFIX:
>          ret = hvcc_array_add_nal_unit(nal_buf, nal_size, nal_type,
>                                        ps_array_completeness, hvcc);
>          if (ret < 0)
> @@ -787,6 +781,15 @@ static int hvcc_add_nal_unit(uint8_t *nal_buf, uint32_t nal_size,
>          if (ret < 0)
>              goto end;
>          break;
> +    case HEVC_NAL_SEI_PREFIX:
> +    case HEVC_NAL_SEI_SUFFIX:
> +        if (nal_size > 2 && *(nal_buf + 2) == HEVC_SEI_TYPE_MASTERING_DISPLAY_INFO) {
> +            ret = hvcc_array_add_nal_unit(nal_buf, nal_size, nal_type,
> +                                          ps_array_completeness, hvcc);
> +            if (ret < 0)
> +                goto end;
> +        }
> +        break;
>      default:
>          ret = AVERROR_INVALIDDATA;
>          goto end;
> @@ -835,6 +838,7 @@ static int hvcc_write(AVIOContext *pb, HEVCDecoderConfigurationRecord *hvcc)
>  {
>      uint8_t i;
>      uint16_t j, vps_count = 0, sps_count = 0, pps_count = 0;
> +    int sei_prefix_count = 0, sei_suffix_count = 0;
>  
>      /*
>       * We only support writing HEVCDecoderConfigurationRecord version 1.
> @@ -925,12 +929,20 @@ static int hvcc_write(AVIOContext *pb, HEVCDecoderConfigurationRecord *hvcc)
>          case HEVC_NAL_PPS:
>              pps_count += hvcc->array[i].numNalus;
>              break;
> +        case HEVC_NAL_SEI_PREFIX:
> +            sei_suffix_count += hvcc->array[i].numNalus;
> +            break;
> +        case HEVC_NAL_SEI_SUFFIX:
> +            sei_prefix_count += hvcc->array[i].numNalus;
> +            break;
>          default:
>              break;
>          }
>      if (!vps_count || vps_count > HEVC_MAX_VPS_COUNT ||
>          !sps_count || sps_count > HEVC_MAX_SPS_COUNT ||
> -        !pps_count || pps_count > HEVC_MAX_PPS_COUNT)
> +        !pps_count || pps_count > HEVC_MAX_PPS_COUNT ||
> +        sei_prefix_count > UINT16_MAX ||
> +        sei_suffix_count > UINT16_MAX)
>          return AVERROR_INVALIDDATA;
>  
>      /* unsigned int(8) configurationVersion = 1; */
>