avformat/matroskaenc: Start new cluster if relative timestamp could not otherwise be stored

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/matroskaenc.c

@@ -1709,6 +1709,14 @@ static int mkv_write_packet_internal(AVFormatContext *s, AVPacket *pkt, int add_
     }
     ts += mkv->tracks[pkt->stream_index].ts_offset;
 
+    if (mkv->cluster_pos != -1) {
+        int64_t cluster_time = ts - mkv->cluster_pts + mkv->tracks[pkt->stream_index].ts_offset;
+        if ((int16_t)cluster_time != cluster_time) {
+            av_log(s, AV_LOG_DEBUG, "Starting new cluster due to timestamp\n");
+            mkv_start_new_cluster(s, pkt);
+        }
+    }
+
     if (!s->pb->seekable) {
         if (!mkv->dyn_bc) {
             if ((ret = avio_open_dyn_buf(&mkv->dyn_bc)) < 0) {