in reply to Ideas for resizing Images..

One thing you could do is try to get a more recent version of GD, which handles PNG and JPEG. I realize that recent versions do not support GIF, but that's okay, because you can just convert all of your GIF images to PNG. :)

If that doesn't really appeal to you, you could use the NETPBM tools to convert and resize, etc. merlyn has a column on using NETPBM tools to create thumbnails, which may be what you need. If the NETPBM tools aren't already installed on your machine, you can get them from ftp://ftp.x.org/contrib/utilities/netpbm-1mar1994.p1.tar.gz (per the link in merlyn's article).