diff --git a/libavformat/utils.c b/libavformat/utils.c
index fb93e3b57ca03b052a8c949e5243c909e7935884..3b1b34e692d92e882e2de25f564461b0507558ba 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -2917,12 +2917,14 @@ static int compute_pkt_fields2(AVFormatContext *s, AVStream *st, AVPacket *pkt){
 
     if(st->cur_dts && st->cur_dts != AV_NOPTS_VALUE && st->cur_dts >= pkt->dts){
         av_log(s, AV_LOG_ERROR,
-               "st:%d error, non monotone timestamps %"PRId64" >= %"PRId64"\n",
+               "Non monotone timestamps in stream number %d: st->cur_dts:%"PRId64" >= pkt->dts:%"PRId64"\n",
                st->index, st->cur_dts, pkt->dts);
         return -1;
     }
     if(pkt->dts != AV_NOPTS_VALUE && pkt->pts != AV_NOPTS_VALUE && pkt->pts < pkt->dts){
-        av_log(s, AV_LOG_ERROR, "st:%d error, pts < dts\n", st->index);
+        av_log(s, AV_LOG_ERROR,
+               "pts < dts in stream number %d\n: pkt->pts:%"PRId64" < pkt->dts:%"PRId64"\n",
+               st->index, pkt->pts, pkt->dts);
         return -1;
     }