The Extractor searches rectangles bigger than the coordinates "standw" and "standh", one at the top and another one at the bottom of the page (which is the way slides are at the time of writing this program) from .pdf(s) inside the input folder. Then it grabs the images in those rectangles and puts them (ordered with a method that also orders them in GitHub [0s are your friend]) in a folder with the name of the .pdf where they came from inside the output folder. "What do I do with this?" you might be asking... Well, take a look at the next section, will you?
Ah, the jewel of the crown, this program grabs images in folders from the input folder and... stitches them into usable pdfs! Yeah, long gone are the days of zooming in and out trying to follow the class! Go wild :D