Quantization, Dither, and Noise Shaping


This applet demonstrates audio effects resulting from Quantization. It is designed for a first insight into the perceptual effects of quantizing an audio signal.

The following functions can be selected on the lower right of the graphical user interface

  • Quantizer 
    • word length w leads to quantization step size Q=2^(w-1)
  • Dither
    • rect dither - uniform probability density function
    • tri dither - triangular probability density function 
    • high-pass dither - triangular probability density function and high-pass power spectral density
  • Noise shaping 
    • first-order H(z)=z^(-1)
    • second-order H(z)=-2z^(-1)+z^(-2)
    • psychoacoustic noise shaping

You can choose between two predefined audio files from our web-server ("audio1.wav" or "audio2.wav") or your own local .wav-file to be processed.

To run the applet you will need at least a Java VM 1.4 or later. Please find the latest JRE (Java Runtime Environment) here.