Getting a warning with audiowrite ( audiowrite​>clipInput​Data)

I'm trying to read an audio file, add a white noise and then write the resampled audio to a file at 48 kHz. I'm getting a warning

" Warning: Data clipped when writing file. > In audiowrite>clipInputData (line 481)"

can someone please help me with that?

clc
clear


[y, Fs] = audioread('test.wav');% y samples from audio with Fs sampling frequency in [Hz]
 
sound(y, Fs);  % listen to the audio input



Sigma = 1;  % Standard deviation of the noise
N = length(y); % sample lenth
w = Sigma*randn(1,N); % Generate Gaussian noise
x = y+w';   % Add noise to the audio signal


figure (1)
plot(x); % Plot the noisy audio signal

figure (2)
plot(y);  % plot the audio

x_sampled = resample(x,3,1); % sampling frequency to 48 kHz

audiowrite('Noisy_resampled.wav',x_sampled, Fs);  % Write the resampled audio to a file
[y, Fs] = audioread('Noisy_resampled.wav'); % Read the resampled audio
sound(y, Fs);

Answer 1

[Richard Burnside]

Probably exceeding the audiowrite range for the data type. ML Docs shows:

Data Type of Y Valid Range for Y

-----------------------------------

uint8 0 <= Y <= 255

int16 -32768 <= Y <= +32767

int32 -2^31 <= Y <= 2^31-1

single -1.0 <= Y <= +1.0

double -1.0 <= Y <= +1.0

"Data beyond the valid range is clipped."

You could try a scalar attenuation of your data.

[carine]

thanks for your response Ricahard. how can I do the scalar attenuation?

[Walter Roberson]

x = x ./ max(abs(x));