Very simple jitter buffer

MumbleSharp/Audio/AudioDecodingBuffer.cs

@@ -35,30 +35,55 @@ public AudioDecodingBuffer(int sampleRate = Constants.DEFAULT_AUDIO_SAMPLE_RATE,
         }
 
         private long _nextSequenceToDecode;
-        private readonly List<BufferPacket> _encodedBuffer = new List<BufferPacket>(); 
-
+        private readonly List<BufferPacket> _encodedBuffer = new List<BufferPacket>();
+
         private IVoiceCodec _codec;
 
-        public int Read(byte[] buffer, int offset, int count)
-        {
-            int readCount = 0;
-            while (readCount < count)
-            {
-                readCount += ReadFromBuffer(buffer, offset + readCount, count - readCount);
-
-                //Try to decode some more data into the buffer
-                if (!FillBuffer())
-                    break;
-            }
+        /// <summary>
+        /// The time, in milliseconds, for the jitter buffer to delay when network data is exhausted. Only updates internally when jitter is detected.
+        /// </summary>
+        public TimeSpan JitterDelay { get; set; } = TimeSpan.FromMilliseconds(350f);
 
-            if (readCount == 0)
-            {
-                //Return silence
-                Array.Clear(buffer, 0, buffer.Length);
-                return count;
-            }
+        private bool isJitterDetected;
+        private bool isJitterTimerRunning;
+        private DateTime jitterTimer = DateTime.UtcNow;
+        private double jitterMillis = 350f;
 
-            return readCount;
+        public int Read(byte[] buffer, int offset, int count)
+        {
+            int readCount = 0;
+
+            if (isJitterTimerRunning && ((DateTime.UtcNow - jitterTimer).TotalMilliseconds > jitterMillis))
+            {
+                isJitterDetected = false;
+                isJitterTimerRunning = false;
+            }
+
+            if (!isJitterDetected)
+            {
+                while (readCount < count)
+                {
+                    readCount += ReadFromBuffer(buffer, offset + readCount, count - readCount);
+
+                    if (readCount == 0)
+                    {
+                        isJitterDetected = true;
+                    }
+
+                    //Try to decode some more data into the buffer
+                    if (!FillBuffer())
+                        break;
+                }
+            }
+
+            if (readCount == 0)
+            {
+                //Return silence
+                Array.Clear(buffer, 0, count);
+                return count;
+            }
+
+            return readCount;
         }
 
         /// <summary>
@@ -68,8 +93,15 @@ public int Read(byte[] buffer, int offset, int count)
         /// <param name="data">The encoded audio packet</param>
         /// <param name="codec">The codec to use to decode this packet</param>
         public void AddEncodedPacket(long sequence, byte[] data, IVoiceCodec codec)
-        {
-            if(sequence == 0)
+        {
+            if (isJitterDetected && !isJitterTimerRunning)
+            {
+                jitterTimer = DateTime.UtcNow;
+                jitterMillis = JitterDelay.TotalMilliseconds;
+                isJitterTimerRunning = true;
+            }
+
+            if (sequence == 0)
                 _nextSequenceToDecode = 0;
 
             if (_codec == null)
@@ -81,7 +113,8 @@ public void AddEncodedPacket(long sequence, byte[] data, IVoiceCodec codec)
             if (_nextSequenceToDecode > sequence)
                 return;
 
-            _encodedBuffer.Add(new BufferPacket {
+            _encodedBuffer.Add(new BufferPacket
+            {
                 Data = data,
                 Sequence = sequence
             });