Formatting can mean anything; you have to be more specific.
After performing a zero-write; it is not possible to recover the original data any longer using software means; only an NSA laboratory would be able to recover some data with extremely expensive methods. The more you do a zero-write or random-write, the less chance even this laboratory recovery will succeed.
Reformat or formatting won't make the data in your hard disk erased permanently. Those formatted files are still stored on the disk just invisible or inaccessible. Only the FAT or NFTS table erased the information about where those data were saved but the real data are still intact there in sectors of the disk.So as long as those data are not overwritten by new data, it's highly possible to recover them. And the MOST Effective way is to rely on some format recovery programs. Recommend you have a try of Wondershare Data Recovery - Format Recovery. It should help.
Of course, formatting won't erase pictures, it's only the system marks it as free space. So the most effective way is to use a recovery software. I know a very good software named freeware recuva, you can google it or download it from here: http://www.tomshardware.com/forum/280846-32-will-recove... good luck~