Not all of my images are square (same height and width).  When these are imported and set to display on the packing slip, the resulting image is severely distorted and often does not look anything like the product. 

All of my images are 1000px wide, but take for example a brake hose where the image may only be 200px high. It comes out looking like this:

instead of this:

I do not want to change the size of my images because that adds too much white space when used inline in my product listings, and it is not practical to create an additional image just for use in the ShippingEasy catalog.

Is there a way to just set the width and maintain the same aspect ratio?