@VoidEclipse Image compression relies mostly on lossy compression algorithms (you will lose quality if you compress them). But the WEBP format seems to have a good compromise between compression and quality compared to JPEG, but i don't know if this site supports that format (i wouldn't like for this site to make the switch cause CDisplay can't read those files).
This site only supports gif (1987), jpeg (1980's), and png (1995) like an old dinosaur. webp (2010) is way too new and too good for this site to support.