Added support for partial PCM frames

src/Discord.Net.Core/Audio/IAudioClient.cs

@@ -21,31 +21,27 @@ namespace Discord.Audio
         /// Creates a new outgoing stream accepting Opus-encoded data.
         /// </summary>
         /// <param name="samplesPerFrame">Samples per frame. Must be 120, 240, 480, 960, 1920 or 2880, representing 2.5, 5, 10, 20, 40 or 60 milliseconds respectively.</param>
-        /// <param name="bufferSize">The size of the internal buffer used for encryption.</param>
         /// <returns></returns>
-        Stream CreateOpusStream(int samplesPerFrame, int bufferSize = 4000);
+        Stream CreateOpusStream(int samplesPerFrame);
         /// <summary>
         /// Creates a new outgoing stream accepting Opus-encoded data. This is a direct stream with no internal timer.
         /// </summary>
         /// <param name="samplesPerFrame">Samples per frame. Must be 120, 240, 480, 960, 1920 or 2880, representing 2.5, 5, 10, 20, 40 or 60 milliseconds respectively.</param>
-        /// <param name="bufferSize">The size of the internal buffer used for encryption.</param>
         /// <returns></returns>
-        Stream CreateDirectOpusStream(int samplesPerFrame, int bufferSize = 4000);
+        Stream CreateDirectOpusStream(int samplesPerFrame);
         /// <summary>
         /// Creates a new outgoing stream accepting PCM (raw) data.
         /// </summary>
         /// <param name="samplesPerFrame">Samples per frame. Must be 120, 240, 480, 960, 1920 or 2880, representing 2.5, 5, 10, 20, 40 or 60 milliseconds respectively.</param>
         /// <param name="bitrate"></param>
-        /// <param name="bufferSize">The size of the internal buffer used for encoding and encryption.</param>
         /// <returns></returns>
-        Stream CreatePCMStream(int samplesPerFrame, int? bitrate = null, int bufferSize = 4000);
+        Stream CreatePCMStream(int samplesPerFrame, int channels = 2, int? bitrate = null);
         /// <summary>
         /// Creates a new direct outgoing stream accepting PCM (raw) data. This is a direct stream with no internal timer.
         /// </summary>
         /// <param name="samplesPerFrame">Samples per frame. Must be 120, 240, 480, 960, 1920 or 2880, representing 2.5, 5, 10, 20, 40 or 60 milliseconds respectively.</param>
         /// <param name="bitrate"></param>
-        /// <param name="bufferSize">The size of the internal buffer used for encoding and encryption.</param>
         /// <returns></returns>
-        Stream CreateDirectPCMStream(int samplesPerFrame, int? bitrate = null, int bufferSize = 4000);
+        Stream CreateDirectPCMStream(int samplesPerFrame, int channels = 2, int? bitrate = null);
     }
 }

src/Discord.Net.WebSocket/Audio/AudioClient.cs

@@ -169,29 +169,29 @@ namespace Discord.Audio
             await _disconnectedEvent.InvokeAsync(ex).ConfigureAwait(false);
         }
 
-        public Stream CreateOpusStream(int samplesPerFrame, int bufferSize = 4000)
+        public Stream CreateOpusStream(int samplesPerFrame)
         {
             CheckSamplesPerFrame(samplesPerFrame);
             var target = new BufferedAudioTarget(ApiClient, samplesPerFrame, _cancelTokenSource.Token);
-            return new RTPWriteStream(target, _secretKey, samplesPerFrame, _ssrc, bufferSize = 4000);
+            return new RTPWriteStream(target, _secretKey, samplesPerFrame, _ssrc);
         }
-        public Stream CreateDirectOpusStream(int samplesPerFrame, int bufferSize = 4000)
+        public Stream CreateDirectOpusStream(int samplesPerFrame)
         {
             CheckSamplesPerFrame(samplesPerFrame);
             var target = new DirectAudioTarget(ApiClient);
-            return new RTPWriteStream(target, _secretKey, samplesPerFrame, _ssrc, bufferSize = 4000);
+            return new RTPWriteStream(target, _secretKey, samplesPerFrame, _ssrc);
         }
-        public Stream CreatePCMStream(int samplesPerFrame, int? bitrate = null, int bufferSize = 4000)
+        public Stream CreatePCMStream(int samplesPerFrame, int channels = 2, int? bitrate = null)
         {
             CheckSamplesPerFrame(samplesPerFrame);
             var target = new BufferedAudioTarget(ApiClient, samplesPerFrame, _cancelTokenSource.Token);
-            return new OpusEncodeStream(target, _secretKey, samplesPerFrame, _ssrc, bitrate, bufferSize);
+            return new OpusEncodeStream(target, _secretKey, channels, samplesPerFrame, _ssrc, bitrate);
         }
-        public Stream CreateDirectPCMStream(int samplesPerFrame, int? bitrate = null, int bufferSize = 4000)
+        public Stream CreateDirectPCMStream(int samplesPerFrame, int channels = 2, int? bitrate = null)
         {
             CheckSamplesPerFrame(samplesPerFrame);
             var target = new DirectAudioTarget(ApiClient);
-            return new OpusEncodeStream(target, _secretKey, samplesPerFrame, _ssrc, bitrate, bufferSize);
+            return new OpusEncodeStream(target, _secretKey, channels, samplesPerFrame, _ssrc, bitrate);
         }
         private void CheckSamplesPerFrame(int samplesPerFrame)
         {

src/Discord.Net.WebSocket/Audio/Streams/OpusEncodeStream.cs

@@ -1,16 +1,22 @@
-namespace Discord.Audio
+using System;
+
+namespace Discord.Audio
 {
     internal class OpusEncodeStream : RTPWriteStream
     {
-        public int SampleRate = 48000;
-        public int Channels = 2;
-        
+        public const int SampleRate = 48000;
+        private int _frameSize;
+        private byte[] _partialFrameBuffer;
+        private int _partialFramePos;
+
         private readonly OpusEncoder _encoder;
 
-        internal OpusEncodeStream(IAudioTarget target, byte[] secretKey, int samplesPerFrame, uint ssrc, int? bitrate = null, int bufferSize = 4000)
-            : base(target, secretKey, samplesPerFrame, ssrc, bufferSize)
+        internal OpusEncodeStream(IAudioTarget target, byte[] secretKey, int channels, int samplesPerFrame, uint ssrc, int? bitrate = null)
+            : base(target, secretKey, samplesPerFrame, ssrc)
         {
-            _encoder = new OpusEncoder(SampleRate, Channels);
+            _encoder = new OpusEncoder(SampleRate, channels);
+            _frameSize = samplesPerFrame * channels * 2;
+            _partialFrameBuffer = new byte[_frameSize];
 
             _encoder.SetForwardErrorCorrection(true);
             if (bitrate != null)
@@ -19,8 +25,27 @@
 
         public override void Write(byte[] buffer, int offset, int count)
         {
-            count = _encoder.EncodeFrame(buffer, offset, count, _buffer, 0);
-            base.Write(_buffer, 0, count);
+            //Assume threadsafe
+            while (count > 0)
+            {
+                if (_partialFramePos + count >= _frameSize)
+                {
+                    int partialSize = _frameSize - _partialFramePos;
+                    Buffer.BlockCopy(buffer, offset, _partialFrameBuffer, _partialFramePos, partialSize);
+                    offset += partialSize;
+                    count -= partialSize;
+                    _partialFramePos = 0;
+
+                    int encFrameSize = _encoder.EncodeFrame(_partialFrameBuffer, 0, _frameSize, _buffer, 0);
+                    base.Write(_buffer, 0, encFrameSize);
+                }
+                else
+                {
+                    Buffer.BlockCopy(buffer, offset, _partialFrameBuffer, _partialFramePos, count);
+                    _partialFramePos += count;
+                    break;
+                }
+            }
         }
 
         protected override void Dispose(bool disposing)

src/Discord.Net.WebSocket/Audio/Streams/RTPWriteStream.cs

@@ -16,13 +16,13 @@ namespace Discord.Audio
         public override bool CanSeek => false;
         public override bool CanWrite => true;
 
-        internal RTPWriteStream(IAudioTarget target, byte[] secretKey, int samplesPerFrame, uint ssrc, int bufferSize = 4000)
+        internal RTPWriteStream(IAudioTarget target, byte[] secretKey, int samplesPerFrame, uint ssrc)
         {
             _target = target;
             _secretKey = secretKey;
             _samplesPerFrame = samplesPerFrame;
             _ssrc = ssrc;
-            _buffer = new byte[bufferSize];
+            _buffer = new byte[4000];
             _nonce = new byte[24];
             _nonce[0] = 0x80;
             _nonce[1] = 0x78;

src/Discord.Net.WebSocket/Audio/Targets/BufferedAudioTarget.cs

@@ -75,4 +75,4 @@ namespace Discord.Audio
             Dispose(true);
         }
     }
-}
+}