Function ost_add

fftools/ffmpeg_mux_init.c:1191–1601

}

static int ost_add(Muxer *mux, const OptionsContext *o, enum AVMediaType type,
                   InputStream *ist, OutputFilter *ofilter, const ViewSpecifier *vs,
                   OutputStream **post)
{
    AVFormatContext *oc = mux->fc;
    MuxStream     *ms;
    OutputStream *ost;
    const AVCodec *enc;
    AVStream *st;
    SchedulerNode src = { .type = SCH_NODE_TYPE_NONE };
    AVDictionary *encoder_opts = NULL;
    int ret = 0, keep_pix_fmt = 0, autoscale = 1;
    int threads_manual = 0;
    AVRational enc_tb = { 0, 0 };
    enum VideoSyncMethod vsync_method = VSYNC_AUTO;
    const char *bsfs = NULL, *time_base = NULL, *codec_tag = NULL;
    char  *next;
    double qscale = -1;

    st = avformat_new_stream(oc, NULL);
    if (!st)
        return AVERROR(ENOMEM);

    ms  = mux_stream_alloc(mux, type);
    if (!ms)
        return AVERROR(ENOMEM);

    // only streams with sources (i.e. not attachments)
    // are handled by the scheduler
    if (ist || ofilter) {
        ret = GROW_ARRAY(mux->sch_stream_idx, mux->nb_sch_stream_idx);
        if (ret < 0)
            return ret;

        ret = sch_add_mux_stream(mux->sch, mux->sch_idx);
        if (ret < 0)
            return ret;

        av_assert0(ret == mux->nb_sch_stream_idx - 1);
        mux->sch_stream_idx[ret] = ms->ost.index;
        ms->sch_idx              = ret;
    }

    ost = &ms->ost;

    if (o->streamid) {
        AVDictionaryEntry *e;
        char idx[16], *p;
        snprintf(idx, sizeof(idx), "%d", ost->index);

        e = av_dict_get(o->streamid, idx, NULL, 0);
        if (e) {
            st->id = strtol(e->value, &p, 0);
            if (!e->value[0] || *p) {
                av_log(ost, AV_LOG_FATAL, "Invalid stream id: %s\n", e->value);
                return AVERROR(EINVAL);
            }
        }