Function parse_packet

libavformat/demux.c:1178–1332

* Parse a packet, add all split parts to parse_queue. * * @param pkt Packet to parse; must not be NULL. * @param flush Indicates whether to flush. If set, pkt must be blank. */

 * @param flush Indicates whether to flush. If set, pkt must be blank.
 */
static int parse_packet(AVFormatContext *s, AVPacket *pkt,
                        int stream_index, int flush)
{
    FormatContextInternal *const fci = ff_fc_internal(s);
    AVStream *st = s->streams[stream_index];
    FFStream *const sti = ffstream(st);
    AVPacket *out_pkt = sti->parse_pkt;
    const AVPacketSideData *sd = NULL;
    const uint8_t *data = pkt->data;
    uint8_t *extradata = sti->avctx->extradata;
    int extradata_size = sti->avctx->extradata_size;
    int size = pkt->size;
    int ret = 0, got_output = flush, pkt_side_data_consumed = 0;

    if (!size && !flush && sti->parser->flags & PARSER_FLAG_COMPLETE_FRAMES) {
        // preserve 0-size sync packets
        compute_pkt_fields(s, st, sti->parser, pkt, pkt->dts, pkt->pts);

        // Theora has valid 0-sized packets that need to be output
        if (st->codecpar->codec_id == AV_CODEC_ID_THEORA) {
            ret = avpriv_packet_list_put(&fci->parse_queue,
                                         pkt, NULL, 0);
            if (ret < 0)
                goto fail;
        }
    }

    if (pkt->side_data_elems)
        sd = av_packet_side_data_get(pkt->side_data, pkt->side_data_elems,
                                     AV_PKT_DATA_NEW_EXTRADATA);
    if (sd) {
        av_assert1(size && !flush);

        sti->avctx->extradata      = sd->data;
        sti->avctx->extradata_size = sd->size;
    }

    while (size > 0 || (flush && got_output)) {
        int64_t next_pts = pkt->pts;
        int64_t next_dts = pkt->dts;
        int len;

        len = av_parser_parse2(sti->parser, sti->avctx,
                               &out_pkt->data, &out_pkt->size, data, size,
                               pkt->pts, pkt->dts, pkt->pos);

        pkt->pts = pkt->dts = AV_NOPTS_VALUE;
        pkt->pos = -1;
        /* increment read pointer */
        av_assert1(data || !len);
        data  = len ? data + len : data;
        size -= len;

        got_output = !!out_pkt->size;

        if (pkt->side_data && !out_pkt->side_data) {
            /* for the first iteration, side_data are simply moved to output.
             * in case of additional iterations, they are duplicated each time. */