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.