From 1cf79e886b466160b118926ba1a1b6905c2904b8 Mon Sep 17 00:00:00 2001
From: ziyue <1213642868@qq.com>
Date: Mon, 12 Jul 2021 21:39:47 +0800
Subject: [PATCH] =?UTF-8?q?=E6=96=B0=E5=A2=9Ertp=E6=97=B6=E9=97=B4?=
 =?UTF-8?q?=E6=88=B3=E5=A4=A7=E5=B9=85=E8=B7=B3=E8=B7=83=E5=A4=84=E7=90=86?=
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---
 src/Common/Stamp.cpp | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/src/Common/Stamp.cpp b/src/Common/Stamp.cpp
index 015168f1..f9df913e 100644
--- a/src/Common/Stamp.cpp
+++ b/src/Common/Stamp.cpp
@@ -224,21 +224,33 @@ void NtpStamp::setNtpStamp(uint32_t rtp_stamp, uint32_t sample_rate, uint64_t nt
 uint64_t NtpStamp::getNtpStamp(uint32_t rtp_stamp, uint32_t sample_rate) {
     uint64_t rtp_stamp_ms = uint64_t(rtp_stamp) * 1000 / sample_rate;
     if (!_rtp_stamp_ms && !_ntp_stamp_ms) {
+        //尚未收到sender report rtcp包
         return rtp_stamp_ms;
     }
+    uint64_t max_rtp_ms = uint64_t(UINT32_MAX) * 1000 / sample_rate;
     if (rtp_stamp_ms > _rtp_stamp_ms) {
-        //时间戳正常增长
-        _last_ret = _ntp_stamp_ms + (rtp_stamp_ms - _rtp_stamp_ms);
+        auto diff = rtp_stamp_ms - _rtp_stamp_ms;
+        if (diff < 10 * 1000) {
+            //时间戳正常增长
+            _last_ret = _ntp_stamp_ms + diff;
+            return _last_ret;
+        }
+        //时间戳大幅跳跃
+        if (_rtp_stamp_ms < 60 * 1000 && rtp_stamp_ms > max_rtp_ms - 60 * 1000) {
+            //应该是rtp时间戳溢出+乱序
+            return _ntp_stamp_ms + diff - max_rtp_ms;
+        }
+        //不明原因的时间戳大幅跳跃，直接返回上次值
         return _last_ret;
     }
-    if (_rtp_stamp_ms - rtp_stamp_ms < 10 * 1000) {
+    auto diff = _rtp_stamp_ms - rtp_stamp_ms;
+    if (diff < 10 * 1000) {
         //小于10秒的时间戳回退，说明收到rtp乱序了
-        return _ntp_stamp_ms - (_rtp_stamp_ms - rtp_stamp_ms);
+        return _ntp_stamp_ms - diff;
     }
-    uint64_t max_rtp_ms = uint64_t(UINT32_MAX) * 1000 / sample_rate;
     if (rtp_stamp_ms < 60 * 1000 && _rtp_stamp_ms > max_rtp_ms - 60 * 1000) {
         //确定是时间戳溢出
-        return _ntp_stamp_ms + rtp_stamp_ms + (max_rtp_ms - _rtp_stamp_ms);
+        return _ntp_stamp_ms + (max_rtp_ms - diff);
     }
     //不明原因的时间戳回退，直接返回上次值
     return _last_ret;