static int mxf_read_packet_old(AVFormatContext *s, AVPacket *pkt)
{
    KLVPacket klv;
    MXFContext *mxf = s->priv_data;
    int ret;

    while ((ret = klv_read_packet(&klv, s->pb)) == 0) {
        PRINT_KEY(s, "read packet", klv.key);
        av_log(s, AV_LOG_TRACE, "size %"PRIu64" offset %#"PRIx64"\n", klv.length, klv.offset);
        if (IS_KLV_KEY(klv.key, mxf_encrypted_triplet_key)) {
            ret = mxf_decrypt_triplet(s, pkt, &klv);
            if (ret < 0) {
                av_log(s, AV_LOG_ERROR, "invalid encoded triplet\n");
                return ret;
            }
            return 0;
        }
        if (IS_KLV_KEY(klv.key, mxf_essence_element_key) ||
            IS_KLV_KEY(klv.key, mxf_canopus_essence_element_key) ||
            IS_KLV_KEY(klv.key, mxf_avid_essence_element_key)) {
            int index = mxf_get_stream_index(s, &klv);
            int64_t next_ofs, next_klv;
            AVStream *st;
            MXFTrack *track;
            AVCodecParameters *par;

            if (index < 0) {
                av_log(s, AV_LOG_ERROR,
                       "error getting stream index %"PRIu32"\n",
                       AV_RB32(klv.key + 12));
                goto skip;
            }

            st = s->streams[index];
            track = st->priv_data;

            if (s->streams[index]->discard == AVDISCARD_ALL)
                goto skip;

            next_klv = avio_tell(s->pb) + klv.length;
            next_ofs = mxf_set_current_edit_unit(mxf, klv.offset);

            if (next_ofs >= 0 && next_klv > next_ofs) {
                /* if this check is hit then it's possible OPAtom was treated as OP1a
                 * truncate the packet since it's probably very large (>2 GiB is common) */
                avpriv_request_sample(s,
                                      "OPAtom misinterpreted as OP1a? "
                                      "KLV for edit unit %i extending into "
                                      "next edit unit",
                                      mxf->current_edit_unit);
                klv.length = next_ofs - avio_tell(s->pb);
            }

            /* check for 8 channels AES3 element */
            if (klv.key[12] == 0x06 && klv.key[13] == 0x01 && klv.key[14] == 0x10) {
                ret = mxf_get_d10_aes3_packet(s->pb, s->streams[index],
                                              pkt, klv.length);
                if (ret < 0) {
                    av_log(s, AV_LOG_ERROR, "error reading D-10 aes3 frame\n");
                    return ret;
                }
            } else {
                ret = av_get_packet(s->pb, pkt, klv.length);
                if (ret < 0)
                    return ret;
            }
            pkt->stream_index = index;
            pkt->pos = klv.offset;

            par = st->codecpar;

            if (par->codec_type == AVMEDIA_TYPE_VIDEO && next_ofs >= 0) {
                /* mxf->current_edit_unit good - see if we have an
                 * index table to derive timestamps from */
                MXFIndexTable *t = &mxf->index_tables[0];

                if (mxf->nb_index_tables >= 1 && mxf->current_edit_unit < t->nb_ptses) {
                    pkt->dts = mxf->current_edit_unit + t->first_dts;
                    pkt->pts = t->ptses[mxf->current_edit_unit];
                } else if (track && track->intra_only) {
                    /* intra-only -> PTS = EditUnit.
                     * let utils.c figure out DTS since it can be < PTS if low_delay = 0 (Sony IMX30) */
                    pkt->pts = mxf->current_edit_unit;
                }
            } else if (par->codec_type == AVMEDIA_TYPE_AUDIO) {
                ret = mxf_set_audio_pts(mxf, par, pkt);
                if (ret < 0)
                    return ret;
            }

            /* seek for truncated packets */
            avio_seek(s->pb, next_klv, SEEK_SET);

            return 0;
        } else
        skip:
            avio_skip(s->pb, klv.length);
    }
    return avio_feof(s->pb) ? AVERROR_EOF : ret;
}