Gallery Module - Square Thumbnail Resize?

I’m working with a layout that requires my thumbnails to be in a square format.

The problem I’m running up against is that when I upload, the images are being squashed to fit into a square. Is there a way to get around this, so that only a portion of the image is cropped, therefore allowing me the square format without altering the aspect ratio of the image?

Please help, it’s driving me crazy!