If you want to recover deleted files, you need to do it as soon as you can. It's also advisable to stop using the device/storage in question until you have. For this reason, recovery is best done via a remote connection.
Files are "deleted" by removing the directory entry, which frees the allocation units up to be overwritten. Even installing recovery software can start to do this. The recovery process reads the original data and recreates the directory entries. It sounds as though the process has gone quite a long way inthis case. Once that's happened, recovery is not possible other than by very specialist software, and this is an expensive process.
The best way of dealign with the whole situation is to make sure all your important files are duplicated somewhere else. In the case of photos, syncing with Dropbox or Google Drive (or even both) is the easiest solution.
