libavformat/utils.c:1808: error: Uninitialized Value
  The value read from start_time[_] was never initialized.

libavformat/utils.c:1808:13: 
1806.             start_time[pkt->stream_index] != AV_NOPTS_VALUE) {
1807.             end_time = pkt->pts;
1808.             duration = end_time - start_time[pkt->stream_index];
                  ^
1809.             if (duration > 0) {
1810.                 if (st->duration == AV_NOPTS_VALUE ||
