How to configure Three20 Lib so that it displays images of variable width/height

I'm using the Three20 library to display a photo gallery in my iphone app but the im开发者_高级运维ages are getting cut off when I click on them. Where do I specify in my Three20 lib (or preferably in my call to Three20) what the image dimensions should be?

The problem turned out to be the xml feed. It was missing the width and height and once I added it in then Three20 was able to scale the image with the correct dimensions.