Image Not Resizing

I am trying to add slider on homepage with 460 * 460 size.

But it shows odd / different sizes for some images. don’t no why? some images scaled perfectly but some comes larger than fixed ratio.

and not for this size only but for any other layout size same issue.

Layout: Slider I. – Large picture Select
Recommended minimum image size is 460 x 460 pixel

The page I need help with: [log in to see the link]