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CFE is able to display details that are not visible on the original image. Look at the third image. What you can see here is not very far from edge detection. The images can be used to create a mask. CFE can be used for many other things like burning effect or blur effect. The possibilities are without limits. You will never get a result corresponding at 100% to the original. All the filters are differents, CFE does not allow to store identical filters even if it accpets to generate the image.

This image comes from Pexels.