Noise in the background when generating a sine wave in Java

Question

I get a little distortion (sounds like a buzz) in the background when I run the following code. Due to his subtle nature, he is convinced that there is some kind of smoothing with the byte.

AudioFormat = PCM_SIGNED 44100.0 Hz, 16 bit, stereo, 4 bytes / frame, big-endian

Note : the code assumes (for now) that the data is at the big end.

public static void playFreq(AudioFormat audioFormat, double frequency, SourceDataLine sourceDataLine)
{
    System.out.println(audioFormat);
    double sampleRate = audioFormat.getSampleRate();
    int sampleSizeInBytes = audioFormat.getSampleSizeInBits() / 8;
    int channels = audioFormat.getChannels();

    byte audioBuffer[] = new byte[(int)Math.pow(2.0, 19.0) * channels * sampleSizeInBytes];

    for ( int i = 0; i < audioBuffer.length; i+=sampleSizeInBytes*channels )
    {
        int wave = (int) (127.0 * Math.sin( 2.0 * Math.PI * frequency * i / (sampleRate * sampleSizeInBytes * channels) )  );

        //wave = (wave > 0 ? 127 : -127);

        if ( channels == 1 )
        {
            if ( sampleSizeInBytes == 1 )
            {
                audioBuffer[i] = (byte) (wave);
            }

            else if ( sampleSizeInBytes == 2 )
            {
                audioBuffer[i] = (byte) (wave);
                audioBuffer[i+1] = (byte)(wave >>> 8);
            }
        }

        else if ( channels == 2 )
        {
            if ( sampleSizeInBytes == 1 )
            {
                audioBuffer[i] = (byte) (wave);
                audioBuffer[i+1] = (byte) (wave);
            }

            else if ( sampleSizeInBytes == 2 )
            {
                audioBuffer[i] = (byte) (wave);
                audioBuffer[i+1] = (byte)(wave >>> 8);

                audioBuffer[i+2] = (byte) (wave);
                audioBuffer[i+3] = (byte)(wave >>> 8);
            }
        }
    }

    sourceDataLine.write(audioBuffer, 0, audioBuffer.length);
}

Answer 1

Your comments say that the code assumes big-endian.

Technically, you are actually outputting to little-endian, however it does not matter, because thanks to a fortunate quirk, your highest byte is always 0.

EDIT: , - 127, (0x00, 0x7f), (0x7f, 0x00) 32512. 16- 32767, 8 . 32767 , 8 , .

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int samples = 2 << 19;
byte audioBuffer[] = new byte[samples * channels * sampleSizeInBytes];

for ( int i = 0, j = 0; i < samples; ++i )
{
    int wave = (int)(32767.0 * Math.sin(2.0 * Math.PI * frequency * i / sampleRate));
    byte msb = (byte)(wave >>> 8);
    byte lsb = (byte) wave;

    for (int c = 0; c < channels; ++c) {
        audioBuffer[j++] = msb;
        if (sampleSizeInBytes > 1) {
            audioBuffer[j++] = lsb;
        }
    }
 }

Answer 2

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:

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  -----/         \       -----/         \       -----/         \
                  \                      \                      \
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