Forget your Samsung phone, just take out the SD card and connect it to a PC via a SD card reader. Try any of the photo recovery software, and your deleted photos should be found as long as they are not overwritten by new files. Photo Recovery is one of the best.
Or unless you really meant to restore files from your Samsung phone memory instead of the SD card, you should try recovery program for mobile phone. In addition, phone internal memory data recovery needs root access.