diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 3922e89..ba33249 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -1479,6 +1479,10 @@ typedef struct AVPacket {
      */
     attribute_deprecated
     int64_t convergence_duration;
+
+    //  add by chenxq
+    int16_t lost_packet;
+
 #endif
 } AVPacket;
 #define AV_PKT_FLAG_KEY     0x0001 ///< The packet contains a keyframe
@@ -6182,4 +6186,4 @@ AVCPBProperties *av_cpb_properties_alloc(size_t *size);
  * @}
  */
 
-#endif /* AVCODEC_AVCODEC_H */
+#endif /* AVCODEC_AVCODEC_H */
\ No newline at end of filediff --git a/libavcodec/avpacket.c b/libavcodec/avpacket.c
index e160ad3..79d0932 100644
--- a/libavcodec/avpacket.c
+++ b/libavcodec/avpacket.c
@@ -46,6 +46,8 @@ FF_ENABLE_DEPRECATION_WARNINGS
     pkt->buf                  = NULL;
     pkt->side_data            = NULL;
     pkt->side_data_elems      = 0;
+    //chenxq
+    pkt->lost_packet          = 0;
 }
 
 AVPacket *av_packet_alloc(void)
@@ -736,4 +738,4 @@ int ff_side_data_set_encoder_stats(AVPacket *pkt, int quality, int64_t *error, i
         AV_WL64(side_data+8 + 8*i , error[i]);
 
     return 0;
-}
+}
\ No newline at end of filediff --git a/libavformat/rtpdec.c b/libavformat/rtpdec.c
index e75a34c..d1e6f14 100644
--- a/libavformat/rtpdec.c
+++ b/libavformat/rtpdec.c
@@ -815,6 +815,10 @@ static int rtp_parse_one_packet(RTPDemuxContext *s, AVPacket *pkt,
         return rtcp_parse_packet(s, buf, len);
     }
 
+    //chenxq
+    uint16_t seq = AV_RB16(buf + 2);
+    int lost_packet = seq - s->seq;
+
     if (s->st) {
         int64_t received = av_gettime_relative();
         uint32_t arrival_ts = av_rescale_q(received, AV_TIME_BASE_Q,
@@ -827,7 +831,7 @@ static int rtp_parse_one_packet(RTPDemuxContext *s, AVPacket *pkt,
 
     if ((s->seq == 0 && !s->queue) || s->queue_size <= 1) {
         /* First packet, or no reordering */
-        return rtp_parse_packet_internal(s, pkt, buf, len);
+    	rv = rtp_parse_packet_internal(s, pkt, buf, len);
     } else {
         uint16_t seq = AV_RB16(buf + 2);
         int16_t diff = seq - s->seq;
@@ -835,26 +839,33 @@ static int rtp_parse_one_packet(RTPDemuxContext *s, AVPacket *pkt,
             /* Packet older than the previously emitted one, drop */
             av_log(s->ic, AV_LOG_WARNING,
                    "RTP: dropping old packet received too late\n");
-            return -1;
+            rv = -1;
         } else if (diff <= 1) {
             /* Correct packet */
             rv = rtp_parse_packet_internal(s, pkt, buf, len);
-            return rv;
         } else {
             /* Still missing some packet, enqueue this one. */
             rv = enqueue_packet(s, buf, len);
-            if (rv < 0)
-                return rv;
-            *bufptr = NULL;
-            /* Return the first enqueued packet if the queue is full,
-             * even if we're missing something */
-            if (s->queue_len >= s->queue_size) {
-                av_log(s->ic, AV_LOG_WARNING, "jitter buffer full\n");
-                return rtp_parse_queued_packet(s, pkt);
+            if (rv >= 0)
+            {
+				*bufptr = NULL;
+				/* Return the first enqueued packet if the queue is full,
+				 * even if we're missing something */
+				if (s->queue_len >= s->queue_size) {
+					av_log(s->ic, AV_LOG_WARNING, "jitter buffer full\n");
+					rv = rtp_parse_queued_packet(s, pkt);
+				}
+				rv = -1;
             }
-            return -1;
         }
     }
+
+    if (lost_packet > 1)
+    {
+    	pkt->lost_packet = lost_packet;
+    }
+
+	return rv;
 }
 
 /**
@@ -873,9 +884,15 @@ int ff_rtp_parse_packet(RTPDemuxContext *s, AVPacket *pkt,
     if (s->srtp_enabled && bufptr && ff_srtp_decrypt(&s->srtp, *bufptr, &len) < 0)
         return -1;
     rv = rtp_parse_one_packet(s, pkt, bufptr, len);
+    int lost_packet = pkt->lost_packet;
     s->prev_ret = rv;
     while (rv < 0 && has_next_packet(s))
         rv = rtp_parse_queued_packet(s, pkt);
+    if (lost_packet > 0)
+    {
+    	pkt->lost_packet = lost_packet;
+    }
+
     return rv ? rv : has_next_packet(s);
 }
 
@@ -937,4 +954,4 @@ int ff_rtp_finalize_packet(AVPacket *pkt, AVIOContext **dyn_buf, int stream_idx)
         return ret;
     }
     return pkt->size;
-}
+}
\ No newline at end of filediff --git a/libavformat/utils.c b/libavformat/utils.c
index 93e588e..0eaf0fa 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -1573,6 +1573,7 @@ static int read_frame_internal(AVFormatContext *s, AVPacket *pkt)
     AVDictionary *metadata = NULL;
 
     av_init_packet(pkt);
+    int lost_packet = 0;
 
     while (!got_packet && !s->internal->parse_queue) {
         AVStream *st;
@@ -1580,6 +1581,8 @@ static int read_frame_internal(AVFormatContext *s, AVPacket *pkt)
 
         /* read next packet */
         ret = ff_read_packet(s, &cur_pkt);
+        if (cur_pkt.lost_packet != 0)
+        	lost_packet = cur_pkt.lost_packet;
         if (ret < 0) {
             if (ret == AVERROR(EAGAIN))
                 return ret;
@@ -1762,6 +1765,9 @@ FF_ENABLE_DEPRECATION_WARNINGS
                av_ts2str(pkt->dts),
                pkt->size, pkt->duration, pkt->flags);
 
+    if (lost_packet != 0)
+    	pkt->lost_packet = lost_packet;
+
     return ret;
 }