Pre emphasis filter in MFCC

The pre emphasis filter is like this:

            Y [n] =  X [n] -0 . 95 x[n - 1]

What is n here?

Answer 1

[Wayne King]

n is the just the "time" index of the discrete-time signal (in this case a speech signal). You can implement this filter in MATLAB as just

 B = [1 -0.95];
 y = filter(B,1,x);

where x is the input signal (speech waveform).

[Anurag Pujari]

Thank you