Choose a photo, select number of cells and apply the filter.
Each number will result in a different image.
The closer to zero higher the contrast, the higher the value more similar to the actual photo.
Then, you can save the photo where you like.
It can read: .jpg, .png, .bmp
It can save: .jpg, .png, .tiff (just add the desired extension to the file to be saved's name)
Show the world what you can do with it.