public static extern int av_opt_get_video_rate(void *obj, byte *name, int search_flags, AVRational *out_val);
public static extern int av_opt_eval_q(void *obj, AVOption *o, byte *val, AVRational *q_out);
private int WriteFrame(AVRational *timeBase, AVStream *stream, AVPacket *pkt) { av_packet_rescale_ts(pkt, *timeBase, stream->time_base); pkt->stream_index = stream->index; return(av_interleaved_write_frame(ctx, pkt)); }