What is meant by companded quantization? - Compression Standard

What is meant by companded quantization?

- Companded Quantization maps the input through compressor function.

- This function expands the probability to the high level regions.

- These regions are close to the origin.

- These regions are compresses the corresponding lower probability regions that are away from the origin.

- The output of Companded Quantization is resulted by using uniform quantizer.

- An expander function is used to transform the quantized value.