I am looking for any type of software that can be run from the terminal that will allow me to see if an image exists in another image. I am screenshotting a website and deciding what action to take after that based on what image the screenshot matches. But it seems as if they website shifts things slightly up and down periodically making this difficult. So what I would like to do is search for just what I'm looking for out of a screenshot of the whole window, that way the shifting would not matter. Thanks for any help!