This has been discussed quite a few times and I hate to say it but you might be out of luck.
The best chance of recovering anything deleted is to stop using the device immediately to the try to recover any files. Big difference between computer and phone though? You cannot remove the internal storage.
I'f you stored the images on an external SD card, you might be able to get something back, if not then all you can do (apart from trying those tools mentioned) is making sure it doesn't happen again.
Sign up for dropbox or similar and configure it to upload the images automatically. This way you don't rely on your phone to store the images.
This is bad practise anyway because phones can die and Samsung would not try to backup your stuff first before replacing it. This is your responsibility.
So if you don't like things like dropbox do yourself a favour and connect your phone to a PC / Mac on regular basis and backup the files manually.
