Sorry Dave, I can't do that.

Try:
flximg.com/500x400/project

To avoid random, add a number (integer):
flximg.com/500x400/project/3

or a filename:
flximg.com/500x400/project/grape-field.jpg

Auto height (keep aspect):
flximg.com/500xauto/project/3

Auto width (keep aspect):
flximg.com/autox500/project/3

Get original size:
flximg.com/auto/project/3