if (_packet.stream_index == _video_stream && !_first_video) {
if (avcodec_decode_video2 (context, _frame, &frame_finished, &_packet) >= 0 && frame_finished) {
if (_packet.stream_index == _video_stream && !_first_video) {
if (avcodec_decode_video2 (context, _frame, &frame_finished, &_packet) >= 0 && frame_finished) {