[core] Fixed MAVG msRcvBuf and msSndBuf (#1289)

Co-authored-by: Maria Sharabayko <msharabayko@haivision.com>
Haivision · May 27, 2020 · 3979f83 · 3979f83
1 parent e7adb3f
commit 3979f83
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Showing 2 changed files with 27 additions and 11 deletions.
diff --git a/srtcore/buffer.cpp b/srtcore/buffer.cpp
@@ -1591,20 +1591,30 @@ void CRcvBuffer::updRcvAvgDataSize(const steady_clock::time_point& now)
    }
    else if (elapsed_ms >= (SRT_MAVG_BASE_PERIOD / SRT_MAVG_SAMPLING_RATE) / SRT_us2ms)
    {
-      /*
-      * Weight last average value between -1 sec and last sampling time (LST)
-      * and new value between last sampling time and now
-      *                                      |elapsed|
-      *   +----------------------------------+-------+
-      *  -1                                 LST      0(now)
-      */
       int instspan;
       int bytescount;
-      int count = getRcvDataSize(bytescount, instspan);
+      const int count = getRcvDataSize(bytescount, instspan);
 
-      m_iCountMAvg      = (int)(((count      * (1000 - elapsed_ms)) + (count      * elapsed_ms)) / 1000);
-      m_iBytesCountMAvg = (int)(((bytescount * (1000 - elapsed_ms)) + (bytescount * elapsed_ms)) / 1000);
-      m_TimespanMAvg    = (int)(((instspan   * (1000 - elapsed_ms)) + (instspan   * elapsed_ms)) / 1000);
+      if (m_iCountMAvg == 0)
+      {
+          // This is the first call, so just take the new value
+          m_iCountMAvg      = count;
+          m_iBytesCountMAvg = bytescount;
+          m_TimespanMAvg    = instspan;
+      }
+      else
+      {
+          /*
+           * Weight last average value between -1 sec from now and last sampling time (LST)
+           * and new value between last sampling time and now
+           *                                      |elapsed|
+           *   +----------------------------------+-------+
+           *  -1 sec                             LST      0(now)
+           */
+          m_iCountMAvg      = avg_iir_w<1000>(m_iCountMAvg,      count,      elapsed_ms);
+          m_iBytesCountMAvg = avg_iir_w<1000>(m_iBytesCountMAvg, bytescount, elapsed_ms);
+          m_TimespanMAvg    = avg_iir_w<1000>(m_TimespanMAvg,    instspan,   elapsed_ms);
+      }
       m_tsLastSamplingTime = now;
 
       HLOGC(dlog.Debug, log << "getRcvDataSize: " << count << " " << bytescount << " " << instspan

diff --git a/srtcore/utilities.h b/srtcore/utilities.h
@@ -985,6 +985,12 @@ inline ValueType avg_iir(ValueType old_value, ValueType new_value)
     return (old_value * (DEPRLEN - 1) + new_value) / DEPRLEN;
 }
 
+template <size_t DEPRLEN, typename ValueType>
+inline ValueType avg_iir_w(ValueType old_value, ValueType new_value, size_t new_val_weight)
+{
+    return (old_value * (DEPRLEN - new_val_weight) + new_value * new_val_weight) / DEPRLEN;
+}
+
 // Property accessor definitions
 //
 // "Property" is a special method that accesses given field.