Help needed to find distortion introduced due to filtering

2007-05-10 10:21:42

Problem Description:

I am splitting an input audio file(wav format) into 32 subbands using a QMF Analysis  filter bank and again reconstructing it using QMF synthesis filter bank. I want to find how the number of  filter co-efficients effect this process. To do this i have built matlab/simulink models with number of filter co-efficients being 20,40,20,80,100. I have passed a wav file through these and also have stored the output wav files.

I want know what is the metric that can be used to measure the distortion introduced due to this filetring. I am looking specifically for an objective value that can quantify the distortion



would be greatfull for all the help

Help needed to find distortion introduced due to filtering

Reply #1 – 2007-05-10 10:52:43

First, maybe the question is posted to the wrong forum. You could expect more help from Scientific/R&D Discussion.

Anyway, it's hard to mesaure the distorsion of a system using plain music audio as the input. THD (total harmonic distortion) is used to express linearity of a system. Ideally, it should be 0 (linear system). But in the real world, it's imposible to achieve. But in your case, this cannot be used because it is measured at specific frequency (usually 1KHz) with the pure sine input.