Take the average value of part of a ByteBuffer (that is actually 16 bit little endian) easily

gistfile1.txt

        // posBefore = where in the mBuffer the new data started (before put)
        
        ShortBuffer avgBuf = ((ByteBuffer) mBuffer.duplicate().flip().position(posBefore))
                .order(ByteOrder.LITTLE_ENDIAN).asShortBuffer();
        long total = 0;
        while (avgBuf.remaining() > 0) {
            total += avgBuf.get() & 0xffff;  // Because unsigned.
        }
        sLastDataAverage = total / numOfBytes / 2 / 65535f;
        Logger.v(TAG, "Analysis of audio data: avg = %f", sLastDataAverage);