[FFmpeg-devel] [PATCH v2 3/7] avformat/matroskadec: export Dynamic HDR10+ packet side data

Andreas Rheinhardt andreas.rheinhardt at outlook.com
Thu Mar 30 03:43:10 EEST 2023


James Almer:
> Signed-off-by: James Almer <jamrial at gmail.com>
> ---
>  libavformat/matroska.h    |  3 ++
>  libavformat/matroskadec.c | 80 +++++++++++++++++++++++++++++++++++----
>  2 files changed, 76 insertions(+), 7 deletions(-)
> 
> diff --git a/libavformat/matroska.h b/libavformat/matroska.h
> index de63cdc7ae..b39517709c 100644
> --- a/libavformat/matroska.h
> +++ b/libavformat/matroska.h
> @@ -360,8 +360,11 @@ typedef enum {
>  
>  typedef enum {
>    MATROSKA_BLOCK_ADD_ID_TYPE_DEFAULT                = 0,
> +  MATROSKA_BLOCK_ADD_ID_TYPE_ITU_T_T35              = 4,
>  } MatroskaBlockAddIDType;
>  
> +#define MATROSKA_BLOCK_ADD_ID_ITU_T_T35 4
> +
>  /*
>   * Matroska Codec IDs, strings
>   */
> diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c
> index 9581b19204..ad8b352f31 100644
> --- a/libavformat/matroskadec.c
> +++ b/libavformat/matroskadec.c
> @@ -40,6 +40,7 @@
>  #include "libavutil/dict.h"
>  #include "libavutil/dict_internal.h"
>  #include "libavutil/display.h"
> +#include "libavutil/hdr_dynamic_metadata.h"
>  #include "libavutil/intfloat.h"
>  #include "libavutil/intreadwrite.h"
>  #include "libavutil/lzo.h"
> @@ -284,6 +285,7 @@ typedef struct MatroskaTrack {
>      int needs_decoding;
>      uint64_t max_block_additional_id;
>      EbmlList block_addition_mappings;
> +    int blockaddid_itu_t_t35;
>  
>      uint32_t palette[AVPALETTE_COUNT];
>      int has_palette;
> @@ -423,6 +425,8 @@ typedef struct MatroskaDemuxContext {
>  
>      MatroskaCluster current_cluster;
>  
> +    int is_webm;
> +
>      /* WebM DASH Manifest live flag */
>      int is_live;
>  
> @@ -2378,7 +2382,7 @@ static int mkv_parse_dvcc_dvvc(AVFormatContext *s, AVStream *st, const MatroskaT
>      return ff_isom_parse_dvcc_dvvc(s, st, bin->data, bin->size);
>  }
>  
> -static int mkv_parse_block_addition_mappings(AVFormatContext *s, AVStream *st, const MatroskaTrack *track)
> +static int mkv_parse_block_addition_mappings(AVFormatContext *s, AVStream *st, MatroskaTrack *track)
>  {
>      const EbmlList *mappings_list = &track->block_addition_mappings;
>      MatroskaBlockAdditionMapping *mappings = mappings_list->elem;
> @@ -2388,6 +2392,18 @@ static int mkv_parse_block_addition_mappings(AVFormatContext *s, AVStream *st, c
>          MatroskaBlockAdditionMapping *mapping = &mappings[i];
>  
>          switch (mapping->type) {
> +        case MATROSKA_BLOCK_ADD_ID_TYPE_ITU_T_T35:
> +            if (mapping->value != MATROSKA_BLOCK_ADD_ID_ITU_T_T35) {
> +                int strict = s->strict_std_compliance >= FF_COMPLIANCE_STRICT;
> +                av_log(s, strict ? AV_LOG_ERROR : AV_LOG_WARNING,
> +                       "Invalid Block Addition Value 0x%"PRIx64" for Block Addition Mapping Type "
> +                       "\"ITU T.35 metadata\"\n", mapping->value);
> +                if (!strict)
> +                    break;
> +                return AVERROR_INVALIDDATA;
> +            }
> +            track->blockaddid_itu_t_t35 = 1;
> +            break;
>          case MKBETAG('d','v','c','C'):
>          case MKBETAG('d','v','v','C'):
>              if ((ret = mkv_parse_dvcc_dvvc(s, st, track, &mapping->extradata)) < 0)
> @@ -2814,10 +2830,12 @@ static int matroska_parse_tracks(AVFormatContext *s)
>              AV_WL16(extradata, 0x410);
>          } else if (codec_id == AV_CODEC_ID_PRORES && track->codec_priv.size == 4) {
>              fourcc = AV_RL32(track->codec_priv.data);
> -        } else if (codec_id == AV_CODEC_ID_VP9 && track->codec_priv.size) {
> +        } else if (codec_id == AV_CODEC_ID_VP9) {
>              /* we don't need any value stored in CodecPrivate.
>                 make sure that it's not exported as extradata. */
>              track->codec_priv.size = 0;
> +            /* Assume BlockAddID 4 is ITU-T T.35 metadata if WebM */
> +            track->blockaddid_itu_t_t35 = matroska->is_webm;
>          } else if (codec_id == AV_CODEC_ID_ARIB_CAPTION && track->codec_priv.size == 3) {
>              int component_tag = track->codec_priv.data[0];
>              int data_component_id = AV_RB16(track->codec_priv.data + 1);
> @@ -3081,6 +3099,8 @@ static int matroska_read_header(AVFormatContext *s)
>              return AVERROR_INVALIDDATA;
>          }
>      }
> +    matroska->is_webm = !strcmp(ebml.doctype, "webm");
> +
>      ebml_free(ebml_syntax, &ebml);
>  
>      matroska->pkt = si->parse_pkt;
> @@ -3615,12 +3635,58 @@ static int matroska_parse_webvtt(MatroskaDemuxContext *matroska,
>  }
>  
>  static int matroska_parse_block_additional(MatroskaDemuxContext *matroska,
> -                                           AVPacket *pkt,
> +                                           MatroskaTrack *track, AVPacket *pkt,
>                                             const uint8_t *data, int size, uint64_t id)
>  {
> -    uint8_t *side_data = av_packet_new_side_data(pkt,
> -                                                 AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
> -                                                 size + 8);
> +    uint8_t *side_data;
> +    int res;
> +
> +    switch (id) {
> +    case 4: {
> +        GetByteContext bc;
> +        int country_code, provider_code;
> +        int provider_oriented_code, application_identifier;
> +        size_t hdrplus_size;
> +        AVDynamicHDRPlus *hdrplus;
> +
> +        if (!track->blockaddid_itu_t_t35)
> +            break; //ignore
> +
> +        bytestream2_init(&bc, data, size);
> +
> +        /* ITU-T T.35 metadata */
> +        country_code  = bytestream2_get_byte(&bc);
> +        provider_code = bytestream2_get_be16(&bc);

This will add implicit overread checks; but you should check size
explicitly instead.
(The current behaviour of the bytestream2 API is to return 0 upon
overreads; yet one should not rely on this and it could e.g. be changed
so that bytestream2_get_byte returns 0xB5 and bytestream2_get_be16 0x3C
upon overread.)

> +
> +        if (country_code != 0xB5 || provider_code != 0x3C)
> +            break; // ignore
> +
> +        provider_oriented_code = bytestream2_get_be16(&bc);
> +        application_identifier = bytestream2_get_byte(&bc);
> +
> +        if (provider_oriented_code != 1 || application_identifier != 4)
> +            break; // ignore
> +
> +        hdrplus = av_dynamic_hdr_plus_alloc(&hdrplus_size);
> +        if (!hdrplus)
> +            return AVERROR(ENOMEM);
> +
> +        if ((res = av_dynamic_hdr_plus_from_t35(hdrplus, bc.buffer,
> +                                                bytestream2_get_bytes_left(&bc))) < 0 ||
> +            (res = av_packet_add_side_data(pkt, AV_PKT_DATA_DYNAMIC_HDR10_PLUS,
> +                                           (uint8_t *)hdrplus, hdrplus_size)) < 0) {
> +            av_free(hdrplus);
> +            return res;
> +        }
> +
> +        return 0;
> +    }
> +    default:
> +        break;
> +    }
> +
> +    side_data = av_packet_new_side_data(pkt, AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
> +                                        size + 8);
>      if (!side_data)
>          return AVERROR(ENOMEM);
>  
> @@ -3692,7 +3758,7 @@ static int matroska_parse_frame(MatroskaDemuxContext *matroska,
>          if (!more->additional.size)
>              continue;
>  
> -        res = matroska_parse_block_additional(matroska, pkt, more->additional.data,
> +        res = matroska_parse_block_additional(matroska, track, pkt, more->additional.data,
>                                                more->additional.size, more->additional_id);
>          if (res < 0) {
>              av_packet_unref(pkt);



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