Use byte buffer for audio to minimize buffer copy's

jni/nv_opus_dec/nv_opus_dec.c

@@ -37,8 +37,8 @@ int nv_opus_get_channel_count(void) {
 }
 
 // This number assumes 2 channels at 48 KHz
-int nv_opus_get_max_out_shorts(void) {
-	return 512*nv_opus_get_channel_count();
+int nv_opus_get_max_out_bytes(void) {
+	return 1024*nv_opus_get_channel_count();
 }
 
 // The Opus stream is 48 KHz
@@ -46,17 +46,20 @@ int nv_opus_get_sample_rate(void) {
 	return 48000;
 }
 
-// outpcmdata must be 5760*2 shorts in length
+// outpcmdata must be 11520*2 bytes in length
 // packets must be decoded in order
 // a packet loss must call this function with NULL indata and 0 inlen
 // returns the number of decoded samples
-int nv_opus_decode(unsigned char* indata, int inlen, short* outpcmdata) {
+int nv_opus_decode(unsigned char* indata, int inlen, unsigned char* outpcmdata) {
 	int err;
 
 	// Decoding to 16-bit PCM with FEC off
 	// Maximum length assuming 48KHz sample rate
 	err = opus_decode(decoder, indata, inlen,
-		outpcmdata, 512, 0);
+		(opus_int16*) outpcmdata, 512, 0);
 
+	if (err>0)
+		err = err * 2;
+		
 	return err;
 }

jni/nv_opus_dec/nv_opus_dec.h

@@ -1,6 +1,6 @@
 int nv_opus_init(void);
 void nv_opus_destroy(void);
 int nv_opus_get_channel_count(void);
-int nv_opus_get_max_out_shorts(void);
+int nv_opus_get_max_out_bytes(void);
 int nv_opus_get_sample_rate(void);
-int nv_opus_decode(unsigned char* indata, int inlen, short* outpcmdata);
+int nv_opus_decode(unsigned char* indata, int inlen, unsigned char* outpcmdata);

jni/nv_opus_dec/nv_opus_dec_jni.c

@@ -25,8 +25,8 @@ Java_com_limelight_nvstream_av_audio_OpusDecoder_getChannelCount(JNIEnv *env, jo
 
 // This number assumes 2 channels at 48 KHz
 JNIEXPORT jint JNICALL
-Java_com_limelight_nvstream_av_audio_OpusDecoder_getMaxOutputShorts(JNIEnv *env, jobject this) {
-	return nv_opus_get_max_out_shorts();
+Java_com_limelight_nvstream_av_audio_OpusDecoder_getMaxOutputBytes(JNIEnv *env, jobject this) {
+	return nv_opus_get_max_out_bytes();
 }
 
 // The Opus stream is 48 KHz
@@ -43,13 +43,13 @@ JNIEXPORT jint JNICALL
 Java_com_limelight_nvstream_av_audio_OpusDecoder_decode(
 	JNIEnv *env, jobject this, // JNI parameters
 	jbyteArray indata, jint inoff, jint inlen, // Input parameters
-	jshortArray outpcmdata) // Output parameter
+	jbyteArray outpcmdata) // Output parameter
 {
 	jint ret;
 	jbyte* jni_input_data;
-	jshort* jni_pcm_data;
+	jbyte* jni_pcm_data;
 
-	jni_pcm_data = (*env)->GetShortArrayElements(env, outpcmdata, 0);
+	jni_pcm_data = (*env)->GetByteArrayElements(env, outpcmdata, 0);
 	if (indata != NULL) {
 		jni_input_data = (*env)->GetByteArrayElements(env, indata, 0);
 
@@ -62,7 +62,7 @@ Java_com_limelight_nvstream_av_audio_OpusDecoder_decode(
 		ret = nv_opus_decode(NULL, 0, jni_pcm_data);
 	}
 
-	(*env)->ReleaseShortArrayElements(env, outpcmdata, jni_pcm_data, 0);
+	(*env)->ReleaseByteArrayElements(env, outpcmdata, jni_pcm_data, 0);
 
 	return ret;
 }

src/com/limelight/binding/audio/JavaxAudioRenderer.java

@@ -6,8 +6,10 @@ import javax.sound.sampled.DataLine;
 import javax.sound.sampled.LineUnavailableException;
 import javax.sound.sampled.SourceDataLine;
 
-import com.limelight.nvstream.av.ShortBufferDescriptor;
+import com.limelight.nvstream.av.ByteBufferDescriptor;
 import com.limelight.nvstream.av.audio.AudioRenderer;
+import java.nio.ByteOrder;
+import java.util.LinkedList;
 
 /**
  * Audio renderer implementation
@@ -16,7 +18,7 @@ import com.limelight.nvstream.av.audio.AudioRenderer;
 public class JavaxAudioRenderer implements AudioRenderer {
 
 	private SourceDataLine soundLine;
-	private SoundBuffer soundBuffer;
+	private LinkedList<ByteBufferDescriptor> soundBuffer;
 	private byte[] lineBuffer;
 	private int channelCount;
 	private int sampleRate;
@@ -33,16 +35,25 @@ public class JavaxAudioRenderer implements AudioRenderer {
 	 * @param length the length of data to be rendered
 	 */
 	@Override
-	public void playDecodedAudio(short[] pcmData, int offset, int length) {
+	public void playDecodedAudio(byte[] pcmData, int offset, int length) {
 		if (soundLine != null) {
 			// Queue the decoded samples into the staging sound buffer
-			soundBuffer.queue(new ShortBufferDescriptor(pcmData, offset, length));
+			if (soundBuffer.size() > STAGING_BUFFERS) {
+				soundBuffer.removeFirst();
+			}
+		
+			soundBuffer.addLast(new ByteBufferDescriptor(pcmData, offset, length));
 			
 			int available = soundLine.available();
 			if (reallocateLines) {
 				// Kinda jank. If the queued is larger than available, we are going to have a delay
 				// so we increase the buffer size
-				if (available < soundBuffer.size()) {
+				int size = 0;
+				for (ByteBufferDescriptor desc : soundBuffer) {
+					size += desc.length;
+				}
+				
+				if (available < size) {
 					System.out.println("buffer too full, buffer size: " + soundLine.getBufferSize());
 					int currentBuffer = soundLine.getBufferSize();
 					soundLine.close();
@@ -60,11 +71,16 @@ public class JavaxAudioRenderer implements AudioRenderer {
 			
 			// If there's space available in the sound line, pull some data out
 			// of the staging buffer and write it to the sound line
-			if (available > 0) {
-				int written = soundBuffer.fill(lineBuffer, 0, available);
-				if (written > 0) {
-					soundLine.write(lineBuffer, 0, written);
+			
+			while (available > 0 && !soundBuffer.isEmpty()) {
+				ByteBufferDescriptor buff = soundBuffer.peek();
+				if (buff.length > available) {
+					break;
 				}
+				
+				available -= soundLine.write(buff.data, buff.offset, buff.length);
+				
+				soundBuffer.remove();
 			}
 		}
 	}
@@ -80,7 +96,7 @@ public class JavaxAudioRenderer implements AudioRenderer {
 	}
 
 	private void createSoundLine(int bufferSize) {
-		AudioFormat audioFormat = new AudioFormat(sampleRate, 16, channelCount, true, true);
+		AudioFormat audioFormat = new AudioFormat(sampleRate, 16, channelCount, true, ByteOrder.nativeOrder()==ByteOrder.BIG_ENDIAN);
 		
 		DataLine.Info info;
 		
@@ -103,7 +119,7 @@ public class JavaxAudioRenderer implements AudioRenderer {
 			
 			soundLine.start();
 			lineBuffer = new byte[soundLine.getBufferSize()];
-			soundBuffer = new SoundBuffer(STAGING_BUFFERS);
+			soundBuffer = new LinkedList<ByteBufferDescriptor>();
 		} catch (LineUnavailableException e) {
 			soundLine = null;
 		}

src/com/limelight/binding/audio/SoundBuffer.java

@@ -1,61 +0,0 @@
-package com.limelight.binding.audio;
-
-import java.nio.ByteBuffer;
-import java.nio.ShortBuffer;
-import java.util.LinkedList;
-
-import com.limelight.nvstream.av.ShortBufferDescriptor;
-
-public class SoundBuffer {
-	
-	private LinkedList<ShortBufferDescriptor> bufferList;
-	private int maxBuffers;
-	
-	public SoundBuffer(int maxBuffers) {
-		this.bufferList = new LinkedList<ShortBufferDescriptor>();
-		this.maxBuffers = maxBuffers;
-	}
-	
-	public void queue(ShortBufferDescriptor buff) {
-		if (bufferList.size() > maxBuffers) {
-			bufferList.removeFirst();
-		}
-		
-		bufferList.addLast(buff);
-	}
-	
-	public int size() {
-		int size = 0;
-		for (ShortBufferDescriptor desc : bufferList) {
-			size += desc.length;
-		}
-		return size;
-	}
-	
-	public int fill(byte[] data, int offset, int length) {
-		int filled = 0;
-		
-		// Convert offset and length to be relative to shorts
-		offset /= 2;
-		length /= 2;
-		
-		ShortBuffer sb = ByteBuffer.wrap(data).asShortBuffer();
-		sb.position(offset);
-		while (length > 0 && !bufferList.isEmpty()) {
-			ShortBufferDescriptor buff = bufferList.getFirst();
-			
-			if (buff.length > length) {
-				break;
-			}
-			
-			sb.put(buff.data, buff.offset, buff.length);
-			length -= buff.length;
-			filled += buff.length;
-			
-			bufferList.removeFirst();
-		}
-		
-		// Return bytes instead of shorts
-		return filled * 2;
-	}
-}