Pictures don't take up much space depending on the file. Most of the time it's usually a .jpeg, .png, or .gif which are common files which hardly take up any space depending on the size of the image and the amount of colors used. Graal graphics are very small so they most likely hardly take up anything. The heads I've been looking at in my file only take up like 1-10kb. 1 megabyte = 1024 kilobytes and 1,000mb = 1gb. So if you downloaded every possible graphic on iClassic it would probably be around 70mb-100mb or so. I have a folder filled with so many graphics and it only takes up 33 mb.

http://scratch.mit.edu/static/projects/pinhead/411427_med.png (Unsupported image host)