return s->format->write_packet(s, pkt->stream_index, pkt->data, pkt->size);
return s->format->write_packet(s, pkt->stream_index, pkt->data, pkt->size, force_pts);
int av_write_packet(AVFormatContext *s, AVPacket *pkt){    /* XXX: currently, an emulation because internal API must change */    return s->format->write_packet(s, pkt->stream_index, pkt->data, pkt->size);}