non-uniform quantization problem?

[davyzhu]

Hi all,
I want to quantize Guassian distribution data use non-uniform quantization. And there are problems:

How to determine the optimal quantization level. Is there any reference?

How to add two non-uniform quantized data?
Shall I convert it back to uniform quantized data.

How to multiply one non-uniform quantized data with a constant?

Any suggestions will be appreciated!
Best regards,
Davy

 

[flatulent]

1. My instincts say to space the levels to include equal areas of the Gaussian curve.

2. It would probably be easier to convert to absolute level, add, and then convert back to your nonlinear levels.

3. you could probably make a lookup table to convert to the new steps of the data. This would be a nonlinear function. This would be faster than converting back to linear, multiply, and reconvert to nonlinear.

 

[me2please]

How to determine the optimal quantization level. Is there any reference?

"Vector Quantization and Signal Compression" by Allen Gersho, Robert M. Gray
Ch.5 - Scalar Quantization I : Structure and Performance
Ch.6 - Scalar Quantization II: Optimality and Design