[FFmpeg-devel] [PATCH] avformat/matroskadec: parse all BlockAdditionMapping elements and export the correct value as BlockAdditional side data

[James Almer]

On 4/5/2023 12:26 PM, James Almer wrote:
> Signed-off-by: James Almer <jamrial at gmail.com>
> ---
>   libavformat/matroskadec.c | 47 +++++++++++++++++++++++++++++++++------
>   1 file changed, 40 insertions(+), 7 deletions(-)
> 
> diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c
> index 3c7c2b7c70..175fad6144 100644
> --- a/libavformat/matroskadec.c
> +++ b/libavformat/matroskadec.c
> @@ -2392,17 +2392,23 @@ static int mkv_parse_block_addition_mappings(AVFormatContext *s, AVStream *st, M
>           MatroskaBlockAdditionMapping *mapping = &mappings[i];
>   
>           switch (mapping->type) {
> +        case MATROSKA_BLOCK_ADD_ID_TYPE_DEFAULT:
> +            av_log(s, AV_LOG_DEBUG,
> +                   "Explicit block Addition Mapping type \"Use BlockAddIDValue\", value %"PRIu64","
> +                   " name \"%s\" found.\n", mapping->value, mapping->name ? mapping->name : "");
> +            break;
> +        case MATROSKA_BLOCK_ADD_ID_TYPE_OPAQUE:
>           case MATROSKA_BLOCK_ADD_ID_TYPE_ITU_T_T35:
> -            if (mapping->value != MATROSKA_BLOCK_ADD_ID_ITU_T_T35) {
> +            if (mapping->value != mapping->type) {
>                   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;
> +                       "0x%"PRIx64", name \"%s\"\n", mapping->value, mapping->type,
> +                       mapping->name ? mapping->name : "");
> +                if (strict)
> +                    return AVERROR_INVALIDDATA;
>               }
> -            track->blockaddid_itu_t_t35 = 1;
> +            track->blockaddid_itu_t_t35 |= mapping->type == MATROSKA_BLOCK_ADD_ID_TYPE_ITU_T_T35;
>               break;
>           case MATROSKA_BLOCK_ADD_ID_TYPE_DVCC:
>           case MATROSKA_BLOCK_ADD_ID_TYPE_DVVC:
> @@ -2412,8 +2418,18 @@ static int mkv_parse_block_addition_mappings(AVFormatContext *s, AVStream *st, M
>               break;
>           default:
>               av_log(s, AV_LOG_DEBUG,
> -                   "Unknown block additional mapping type 0x%"PRIx64", value %"PRIu64", name \"%s\"\n",
> +                   "Unknown Block Addition Mapping type 0x%"PRIx64", value %"PRIu64", name \"%s\"\n",
>                      mapping->type, mapping->value, mapping->name ? mapping->name : "");
> +            if (mapping->value < 2) {
> +                int strict = s->strict_std_compliance >= FF_COMPLIANCE_STRICT;
> +                av_log(s, strict ? AV_LOG_ERROR : AV_LOG_WARNING,
> +                       "Invalid Block Addition value 0x%"PRIu64" for unknown Block Addition Mapping "
> +                       "type %"PRIx64", name \"%s\"\n", mapping->value, mapping->type,
> +                       mapping->name ? mapping->name : "");
> +                if (strict)
> +                    return AVERROR_INVALIDDATA;
> +            }
> +            break;
>           }
>       }
>   
> @@ -3638,6 +3654,8 @@ static int matroska_parse_block_additional(MatroskaDemuxContext *matroska,
>                                              MatroskaTrack *track, AVPacket *pkt,
>                                              const uint8_t *data, int size, uint64_t id)
>   {
> +    const EbmlList *mappings_list = &track->block_addition_mappings;
> +    MatroskaBlockAdditionMapping *mappings = mappings_list->elem, *mapping = NULL;
>       uint8_t *side_data;
>       int res;
>   
> @@ -3685,6 +3703,21 @@ static int matroska_parse_block_additional(MatroskaDemuxContext *matroska,
>           break;
>       }
>   
> +    for (int i = 0; i < mappings_list->nb_elem; i++) {
> +        if (id != mappings[i].value)
> +            continue;
> +        mapping = &mappings[i];
> +        break;
> +    }
> +
> +    if (id != 1 && !matroska->is_webm && !mapping) {
> +        av_log(matroska->ctx, AV_LOG_WARNING, "BlockAddID %"PRIu64" has no mapping. Skipping\n", id);
> +        return 0;
> +    }
> +
> +    if (mapping && mapping->type)
> +        id = mapping->type;
> +
>       side_data = av_packet_new_side_data(pkt, AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
>                                           size + (size_t)8);
>       if (!side_data)

Will apply.