In order to recover permanently deleted photos from an iPhone you will need to use an iCloud or iTunes backup to restore the images. Deleted photos are retained on the device temporarily, but once the photos have been removed from the Recently Deleted album, this is your only option.
Deleted photos are moved to the Recently Deleted album before being permanently deleted. To find the photos, open the Photos app and navigate to the Recently Deleted album. At that point, you can select all of the images or specific photos and select Recover to perform the restore.
To recover deleted pictures:
To recover videos that were permanently deleted:
To recover files from a hard drive:
There are a number of photo recovery software applications that offer a free trial period or allow data recovery at no cost. They include: