Fix integer overflow on large wav files and issue #5.

aisp-core/aisp-core-main/src/main/java/org/eng/aisp/util/PCMUtil.java

@@ -99,7 +99,7 @@ public static double[] pcm2Double(byte[] samples, int channels, int bitsPerSampl
 			throw new IllegalArgumentException("bits per sample must be 8, 16,24, or 32");
 		if (channels <= 0) 
 			throw new IllegalArgumentException("channels must be larger than 0");
-		int sampleCount = samples.length * 8 / (bitsPerSample *  channels);
+		int sampleCount = samples.length / bitsPerSample / channels * 8;
 		double result[] = new double[sampleCount];
 		ByteBuffer byteBuffer = ByteBuffer.wrap(samples);
 		byteBuffer.order(ByteOrder.LITTLE_ENDIAN);