audio signal in spectrogram

Hello,

How to apply window function for a audio signal in spectrogram and compare it with the one without applying window function ?

[Gokul]

Can some one explain with a example please

Answer 1

[Wayne King]

You can supply the window argument as a vector.

Signal

    t=0:0.001:2;                   
    x=chirp(t,0,1,150);

Now to find the short-time Fourier transforms

    % without a window
    win = ones(200,1);
    [S,F,T] = spectrogram(x,win,100,200,1000);

    % with a hamming window
    win = hamming(200);
    [Swin,Fwin,Twin] = spectrogram(x,win,100,200,1000);

[Gokul]

Thank you Mr.wayne

[Gokul]

I have assumed : x=wavread('tiggers.wav'); now how to analyze the spectrogram() for this with and without window? Is this the following way % without a window [S,F,T] = spectrogram(x); % with a hamming window win = hamming(200); [Swin,Fwin,Twin] = spectrogram(x,win,100,fs);

suggest please

[Wayne King]

[S,F,T] = spectrogram(x);

is not without a window. If you read the documentation, you'll see that syntax uses a Hamming window.

I've shown you how to not use a window function above. Use a vector of ones, or rectwin()

Answer 2

[UMAIR RASOOL]

close all

clear all

clc

[y,Fs]=audioread('black_hole.mp3');

windowSize = 256;

windowOverlap = [];

freqRange = 0:Fs;

spectrogram(y(:,1), windowSize, windowOverlap, freqRange, Fs, 'xaxis');