Apply filter to sound

Hi everyone

I was wondering what is the proper way to apply lets say a lowpass Butterworth filter and a hamming window into a sound i just loaded in Matlab?

Thanks in advance.

Answer 1

[Wayne King]

Not sure why you want to apply both the Hamming window and use the Butterworth filter. But say you have the Butterworth filter as coefficients B and A, then use:

output = filter(B,A,input);

If you have the Butterworth filter as a filter object, Hd,

    output = filter(Hd,input);

If you wanted to apply the Hamming window before you filter,

      output = filter(B,A,input.*hamming(length(input)));

After filtering,

        output = output.*hamming(length(output));

[Raldi]

Thanks Wayne, very useful comment.