more accurate loading of mp3 files

examples/Advanced/loadFileIntoBuffer/loadFileIntoBuffer.pde

@@ -24,7 +24,6 @@ void setup()
 
   // create Minim and an AudioOutput
   minim  = new Minim(this);
-  minim.debugOn();
   output = minim.getLineOut();
 
   // construct a new MultiChannelBuffer with 2 channels and 1024 sample frames.
@@ -36,16 +35,7 @@ void setup()
   // we pass the buffer to the method and Minim will reconfigure it to match 
   // the file. if the file doesn't exist, or there is some other problen with 
   // loading it, the function will return 0 as the sample rate.
-  float sampleRate = 0;
-  try
-  {
-    sampleRate = minim.loadFileIntoBuffer( "SD.mp3", sampleBuffer );
-  }
-  catch( Exception ex )
-  {
-    println( ex.toString() );
-    ex.printStackTrace();
-  }
+  float sampleRate = minim.loadFileIntoBuffer( "SD.wav", sampleBuffer );
 
   // make sure the file load worked
   if ( sampleRate > 0 )

src/ddf/minim/Minim.java

@@ -646,21 +646,34 @@ public float loadFileIntoBuffer( String filename, MultiChannelBuffer outBuffer )
 					readBuffer.setBufferSize( (int)(totalSampleCount - totalSamplesRead) );
 				}
 
-				stream.read( readBuffer );
+				int samplesRead = stream.read( readBuffer );
+
+				if ( samplesRead == 0 )
+				{
+					debug( "loadSampleIntoBuffer: got 0 samples read" );
+					break;
+				}
 
 				// copy data from one buffer to the other.
 				for(int i = 0; i < channelCount; ++i)
 				{
 					// a faster way to do this would be nice.
-					for(int s = 0; s < readBuffer.getBufferSize(); ++s)
+					for(int s = 0; s < samplesRead; ++s)
 					{
 						outBuffer.setSample( i, (int)totalSamplesRead+s, readBuffer.getSample( i, s ) );
 					}
 				}
 
-				totalSamplesRead += readBuffer.getBufferSize();
+				totalSamplesRead += samplesRead;
 			}
 
+			if ( totalSamplesRead != totalSampleCount )
+			{
+				outBuffer.setBufferSize( (int)totalSamplesRead );
+			}
+
+			debug("loadSampleIntoBuffer: final output buffer size is " + outBuffer.getBufferSize() );
+
 			stream.close();
 		}
 	    else

src/ddf/minim/javasound/JSAudioInput.java

@@ -156,7 +156,7 @@ public float[] read()
 		return samples;
 	}
 
-	public void read(MultiChannelBuffer buffer) 
+	public int read(MultiChannelBuffer buffer) 
 	{
 		// create our converter object
 		int numChannels = line.getFormat().getChannels();
@@ -176,5 +176,7 @@ public void read(MultiChannelBuffer buffer)
 		{
 			buffer.setChannel(i, convert.getChannel(i));
 		}
+
+		return numSamples;
 	}
 }

src/ddf/minim/javasound/JSAudioRecording.java

@@ -353,8 +353,8 @@ public float[] read()
         return null;
     }
 
-    public void read(MultiChannelBuffer buffer)
+    public int read(MultiChannelBuffer buffer)
     {
-
+    	return 0;
     }
 }

src/ddf/minim/javasound/JSAudioRecordingClip.java

@@ -154,8 +154,8 @@ public float[] read()
 		return null;
 	}
 
-	public void read(MultiChannelBuffer buffer)
+	public int read(MultiChannelBuffer buffer)
 	{
-
+		return 0;
 	}
 }

src/ddf/minim/javasound/JSBaseAudioRecordingStream.java

@@ -202,7 +202,7 @@ private void sleep(int millis)
         }
     }
 
-    private void readBytes()
+    private int readBytes()
     {
         int bytesRead = 0;
         int toRead = rawBytes.length;
@@ -236,6 +236,8 @@ private void readBytes()
             system.error( "Error reading from the file - " + e.getMessage() );
         }
         totalBytesRead += bytesRead;
+
+        return bytesRead;
     }
 
     private void readBytesLoop()
@@ -663,16 +665,17 @@ public float[] read()
     }
 
     // FIXME: temporary implementation of read
-    public void read(MultiChannelBuffer outBuffer)
+    public int read(MultiChannelBuffer outBuffer)
     {
         if ( buffer.getSampleCount() != outBuffer.getBufferSize() )
         {	
             buffer.changeSampleCount( outBuffer.getBufferSize(), true );
             rawBytes = new byte[buffer.getByteArrayBufferSize( format )];
         }
+        int framesRead = 0;
         if ( play )
         {
-            mRead();
+        	framesRead = mRead();
         }
         else
         {
@@ -682,24 +685,30 @@ public void read(MultiChannelBuffer outBuffer)
         {
             outBuffer.setChannel( i, buffer.getChannel(i) );
         }
+
+        return framesRead;
     }
 
-    private void mRead()
+    // returns number of samples read, not bytes
+    private int mRead()
     {
         // read in a full buffer of bytes from the file
+    	int bytesRead = rawBytes.length;
         if ( loop )
         {
             readBytesLoop();
         }
         else
         {
-            readBytes();
+            bytesRead = readBytes();
         }
         // convert them to floating point
+        int frameCount = bytesRead / format.getFrameSize();
         synchronized ( buffer )
         {
-            int frameCount = rawBytes.length / format.getFrameSize();
             buffer.setSamplesFromBytes( rawBytes, 0, format, 0, frameCount );
         }
+
+        return frameCount;
     }
 }

src/ddf/minim/spi/AudioStream.java

@@ -46,6 +46,8 @@ public interface AudioStream extends AudioResource
    * AudioStream does.
    * 
    * @param buffer The MultiChannelBuffer to fill with audio samples.
+   * 
+   * @return int: the number of sample frames that were actually read, could be smaller than the size of the buffer.
    */
-  void read(MultiChannelBuffer buffer);
+  int read(MultiChannelBuffer buffer);
 }