I am looking for a call that will return the image type: jpg, png, gif, bmp, and so on.

getBareImageType()

Or something like that. Does that exist?

getSuffix(imageobj->filename)

Didn't work for me:

Parse error: syntax error, unexpected T_STRING in ... on line 75

EDIT:

Actually this is the error I am getting now:

Parse error: syntax error, unexpected T_OBJECT_OPERATOR in ... on line 75

I did a search on this call:
getFullImageURL();
to match it up with .jpg and so on, to determine the filetype.
It's a pretty hackish, but it works for now.