Is it possible to add some pre-processing of the background/overlay image so when admin uploads a picture at any size (for example, front side picture may be bigger, back side picture may be smaller), but on the front end, they look the same size and also please center the picture inside the design frame so they always appear at the center both horizontally and vertically.

Thanks.

I understand, but i think background/overlay image need to same size. Becauuse all objects when add to design should below overlay image and above background image. So they need to same size to create design area visible for everyone can understand which parts will print in this design, which are not.

I am not talking about different sizes from background image to overlay image. Of course the background image and overlay image for same side is of same size. But I’m talking about possibly using different size image on front side image and back side image. But I want them to look like same size image on frontend. Also I want them to be auto centered in the frame — right now the image is loaded at the left side of the frame — see here: http://www.logo2go.com/accessories/towel/beach-towel.html

Do you mean about centered design area?
http://screencast.com/t/dRdHoNC8
It’s possible.
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