How do i plot an audio file with an interval in ms?

20 views (last 30 days)
Hi! I am currently using matlab 2021 version. I want to know how would I plot an audio file in the interval of 20 miliseconds of my choice for example the audio recording is 10 seconds long but, I want to plot only from 0 to 20 miliseconds. How would I do that? This is my code right now
recObj = audiorecorder;
Fs=8000;
filename = sprintf('myAudioData.wav');
disp('Start speaking.')
recordblocking(recObj, 10);
disp('End of Recording.');
doubleArray = getaudiodata(recObj);
audiowrite(filename,doubleArray,Fs);
[x,Fs] = audioread('myAudioData.wav');
[m,n]=size(x);
dt=1/Fs;
t=dt*(0:m-1);
idx = (t>=1.030) & (t<1.032);
selected_t = t(idx);
selected_x = x(idx,:);
plot(selected_t, selected_x);

Accepted Answer

Scott MacKenzie
Scott MacKenzie on 22 Mar 2022
Edited: Scott MacKenzie on 22 Mar 2022
Using the sample frequency of the audio data (Fs), this code will extract and plot the first 20 ms:
[x, Fs] = audioread('AudioSample.wav'); % test audio file
ts = 1 / Fs; % duration of each sample
n = round(0.02/ts); % number of samples in 1st 20 ms
plot(x(1:n)); % plot 1st 20 ms of audio file
  5 Comments

Sign in to comment.

More Answers (1)

KSSV
KSSV on 22 Mar 2022
idx = t <= 20*10^-3 ;
plot(t(idx),x(idx))

Categories

Find more on Audio I/O and Waveform Generation in Help Center and File Exchange

Products


Release

R2021b

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!