static void mov_parse_stsd_video(MOVContext *c, AVIOContext *pb,
                                 AVStream *st, MOVStreamContext *sc)
{
    uint8_t codec_name[32] = { 0 };
    int64_t stsd_start;
    unsigned int len;
    uint32_t id = 0;

    /* The first 16 bytes of the video sample description are already
     * read in ff_mov_read_stsd_entries() */
    stsd_start = avio_tell(pb) - 16;

    avio_rb16(pb); /* version */
    avio_rb16(pb); /* revision level */
    id = avio_rl32(pb); /* vendor */
    av_dict_set(&st->metadata, "vendor_id", av_fourcc2str(id), 0);
    avio_rb32(pb); /* temporal quality */
    avio_rb32(pb); /* spatial quality */

    st->codecpar->width  = avio_rb16(pb); /* width */
    st->codecpar->height = avio_rb16(pb); /* height */

    avio_rb32(pb); /* horiz resolution */
    avio_rb32(pb); /* vert resolution */
    avio_rb32(pb); /* data size, always 0 */
    avio_rb16(pb); /* frames per samples */

    len = avio_r8(pb); /* codec name, pascal string */
    if (len > 31)
        len = 31;
    mov_read_mac_string(c, pb, len, codec_name, sizeof(codec_name));
    if (len < 31)
        avio_skip(pb, 31 - len);

    if (codec_name[0])
        av_dict_set(&st->metadata, "encoder", codec_name, 0);

    /* codec_tag YV12 triggers an UV swap in rawdec.c */
    if (!strncmp(codec_name, "Planar Y'CbCr 8-bit 4:2:0", 25)) {
        st->codecpar->codec_tag = MKTAG('I', '4', '2', '0');
        st->codecpar->width &= ~1;
        st->codecpar->height &= ~1;
    }
    /* Flash Media Server uses tag H.263 with Sorenson Spark */
    if (st->codecpar->codec_tag == MKTAG('H','2','6','3') &&
        !strncmp(codec_name, "Sorenson H263", 13))
        st->codecpar->codec_id = AV_CODEC_ID_FLV1;

    st->codecpar->bits_per_coded_sample = avio_rb16(pb); /* depth */

    avio_seek(pb, stsd_start, SEEK_SET);

    if (ff_get_qtpalette(st->codecpar->codec_id, pb, sc->palette)) {
        st->codecpar->bits_per_coded_sample &= 0x1F;
        sc->has_palette = 1;
    }
}
static void mov_parse_stsd_video(MOVContext *c, AVIOContext *pb,
                                 AVStream *st, MOVStreamContext *sc)
{
    uint8_t codec_name[32] = { 0 };
    int64_t stsd_start;
    unsigned int len;
    uint32_t id = 0;

     
    stsd_start = avio_tell(pb) - 16;

    avio_rb16(pb);  
    avio_rb16(pb);  
    id = avio_rl32(pb);  
    av_dict_set(&st->metadata, "vendor_id", av_fourcc2str(id), 0);
    avio_rb32(pb);  
    avio_rb32(pb);  

    st->codecpar->width  = avio_rb16(pb);  
    st->codecpar->height = avio_rb16(pb);  

    avio_rb32(pb);  
    avio_rb32(pb);  
    avio_rb32(pb);  
    avio_rb16(pb);  

    len = avio_r8(pb);  
    if (len > 31)
        len = 31;
    mov_read_mac_string(c, pb, len, codec_name, sizeof(codec_name));
    if (len < 31)
        avio_skip(pb, 31 - len);

    if (codec_name[0])
        av_dict_set(&st->metadata, "encoder", codec_name, 0);

     
    if (!strncmp(codec_name, "Planar Y'CbCr 8-bit 4:2:0", 25)) {
        st->codecpar->codec_tag = MKTAG('I', '4', '2', '0');
        st->codecpar->width &= ~1;
        st->codecpar->height &= ~1;
    }
     
    if (st->codecpar->codec_tag == MKTAG('H','2','6','3') &&
        !strncmp(codec_name, "Sorenson H263", 13))
        st->codecpar->codec_id = AV_CODEC_ID_FLV1;

    st->codecpar->bits_per_coded_sample = avio_rb16(pb);  

    avio_seek(pb, stsd_start, SEEK_SET);

    if (ff_get_qtpalette(st->codecpar->codec_id, pb, sc->palette)) {
        st->codecpar->bits_per_coded_sample &= 0x1F;
        sc->has_palette = 1;
    }
}