static int mov_metadata_gnre(MOVContext *c, AVIOContext *pb,
                             unsigned len, const char *key)
{
    short genre;

    avio_r8(pb); // unknown

    genre = avio_r8(pb);
    if (genre < 1 || genre > ID3v1_GENRE_MAX)
        return 0;
    c->fc->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
    av_dict_set(&c->fc->metadata, key, ff_id3v1_genre_str[genre-1], 0);

    return 0;
}