I was a CVS photo Lab technician and I have printed one about a year ago for the canadian passport .I believe its similar or same for the visa application too.  It was a bit hard.. going thru all those specifications. I remember other than the size, there was supposed to be the store stamp with the printed date the picture was taken. The customer called me after her picture was accepted by the embassy and thanked me.
               Most stores have the specifications for all countries with them, but to be in safe side,Print out the page that has all the detail instructions for the photo and give it to the lab technician. I m sure, they will do it.