Originally Posted by BOBKUSPE
Someone have an image with a lot of data, but to hidden some information he put a black image on it
How I discover the image below the black bar?
You can try using a masking gradient tool; for that, it kind of splits a set of pixels into different layers, allowing you to choose which set you want to edit. By carving out the pixels you don't need, you will be able to see the picture. I don't know if there's an actual software specifically designed for doing this though.