Photo recovery software is essentially a cut down version of full data recovery program but designed to recover photo or video file types such as .jpg, .avi, ,mpeg etc
However in certain data loss situations orphan files can be recovered (those that have lost their file type) and these may not be corrupt.
They would not necessarily be recovered by photo recovery software because it does not identify itself as a photo.
To be sure of recovering all images /pictures / photo / video files, use a full data recovery software program like R3Cover from abc Data Recovery Ltd, both Mac and Windows versions are available and a useful preview feature enables you to view recovered files before buying the software.
Because of the file size of digital photos and movies which can be from aless than a single gigabyte to many hundreds, any overwriting of lost data could result in the recovered picture being damaged / corrupted.
To prevent further risk to digital photos when performing photo recovery using software, never install data recovery programs, recovered data or new data to any drive you intend recovering photos from.