1) the easiest and Most obvious option is to make a div's instead of photos and pictures ask the kitty to these div'am. This is the least of the problems if there is no need for these pictures, for example, copy.
2) Create CSS styles that will be handling your images. Height, most likely, the number will be the same
3) Create a backend that will pass through the images and resize them to the desired size. (the most difficult and likely not effective)