How can I remove white place from image

-- url of the page with the problem -- : kosmima-gkiotli.gr
-- HikaShop version -- : 2.5.0
-- Joomla version -- : 3.4.3
-- PHP version -- : 5.3.10
-- Browser(s) name and version -- : firefox 38.0.1

Hi,
I have tried for hours before I sent the message, as I belived that i could find something to help me, but I not found. I know it is simple but I don't now how to do. So I want the image of the product to cover all the place of it's frame so that it wiil be with out white areas. On the image I explaine what I want.

Thanks on advance

Ok, I have found it, it is from menu configuration->basic->images the Force images size turn to "no" and Image scale mode turn to "crop".