How to increase the length of an audio file with random white noise?

Hi, sorry if this does not make too much sense but here goes.

I have audio files, which are a second or less. I want to add random noise to the audio file (which is a wave file) at different levels of distortion too, so that the total audio length is 2.5 seconds. The level of random noise should be adjustable.

I am complete newby at Matlab and would appreciate the help.

Answer 1

[Image Analyst]

Use the semicolon operator. For a mono signal

[y, Fs] = audioread('guitartune.wav');
% Crop to 1 second
y = y(1:Fs);
% soundsc(y, Fs);
% Make noise
noiseSignal = rand(length(y), 1);
% Concatenate noise.
outputSignal = [y; noiseSignal];
% Play the sound
soundsc(outputSignal, Fs);