How to know that periodic noise is present in an image or not.

Given a set of images that initally do not have periodic noise. Now from whole set we select some random images and introduce some periodic noise to them.

Now i have the whole set from which some images have periodic noises. And i have to write a code to recognise which images have been modified or which images have periodic noise.

Here i do not have the periodic noise which is inserted, i only have a set of images which include modified as well as originall images and now i have to tell which images are modified.

[Vineet Gupta]

can we analyse spectrum to recognise whether original image has peridic noise or not

Answer 1

[Pranav Verma]

Hi Vineet,

As pointed by you in the comments, you can try analysing the spectrum of the image for periodic noise. You can try FFT for this purpose. Please find below the documentation for the FFT in MATLAB:

https://www.mathworks.com/help/matlab/ref/fft.html

For further information on how to check the periodicity of a signal in MATLAB, please refer to the below link:

https://www.mathworks.com/help/signal/ug/find-periodicity-using-frequency-analysis.html#:~:text=Spectral%20analysis%20can%20help%20determine,the%20temperature%20to%20degrees%20Celsius.

[Vineet Gupta]

Thank but this doesn't help