// what recovery returnsThe images, usually. The filenames, often not.
Before you make a decision on whether to attempt recovery, you should know that.
If the file system index survived, when we recover the images, they will include their original name and directory tree. If the index did survive then the images would be recovered by the filename or path to that image. But if the index was destroyed, e.g. due to a complete format or extreme file system corruption, we cannot determine what those files were called. Instead, we scan the damaged media for byte signatures of common photo formats such as JPEG, HEIC, CR2, CR3, NEF, ARW, RAF and DNG. Once we find an appropriate signature at the start of a file, we rebuild the rest of the file from the signature.
Photographs lend themselves to carving well because the format used for photograph files is generally quite large, very structured and very distinct. Carving cannot restore your filename or where it was located as those were both stored within an index that no longer exists.
EXIF is where carving gets lucky. Capture date, camera body, lens, and settings, etc., are contained inside the actual image file; therefore a carved group can be sorted in shooting order even when each file comes back with only a number. Generally speaking, that means a family holiday or a wedding will reassemble in chronological order, and most of the time that is exactly what we want.