Hi NeverSayDie...thanks for the reply.
photorec seems like a great program, and I recovered a ton of stuff with it, but it was all stuff that I had backed up before the format, (or don't need.)
Photorec does not look for the GPS data that I forgot to back up, mostly Garmin .gdb files, maybe some GPX (GPS eXchange Format/XML files.)
I have been trying to figure out how to add a gdb (Garmin database) signature to the photorec program.
There are very few references to the process online, and what little I could find seem to indicate that you need be a professional code-writer. I am not. But, neversaydie, eh? I love a challenge. Maybe I can "reverse-engineer" something, if I have enough clues. Here are the clues that I found:
Not much to work with. I tried everything.
You have to read the hexadecimal code of the file you want to make a signature for.
I used 3 different programs while figuring out what that means. Search "hex code reader"
I liked this one best, only for its copy/paste options, which are really handy during this process ...
The hex tab gives you the code.
The photorec program downloads with testdisk and latest versions include support to add custom signatures.
fidentify is in the folder with the rest, and it is capable of registering your new custom signature with photorec, so the program will look for the desired files. fidentify will also check files to see of photorec is already searching for them, but I haven't figured out how to make it do that yet.
I tried and tried to get fidentify to register a new sig, but kept failing.
I was putting the sig in a text file, in the same folder as photorec and all the rest.
Then clicking the fidentify program.
But the fidentify .txt log showed zero recognition of the new signatures.
I even tried putting in signatures that were file types already being searched by photorec.
I figured it was a format issue, maybe my microsoft text programs weren't recognized, as they remained .txt files no matter what I named them. There are several other text files that download with the testdisk stuff. None of them display extensions, but all will open with notepad or wordpad, etc. They are called INFO, READ ME, AUTHORS, THANKS, but do not show a program icon association, hmm.
I opened INFO with wordpad, deleted the contents, and pasted in a signature. Renamed the file "photrec.sig"
Clicked fidentify, and it worked. The fidentify.txt log showed that I had registered a new signature with photorec.
I ran photorec and recovered a bunch of (supposed) Garmin database files, gdb.
I think I used this signature...I tried a few variations.
gdb 0 0x4D735263660002
I have no idea what all this means.
But I looked at a lot of hex to figure it.
After all that, garmin mapsource would not open the recovered files.
And, curiously, most of the recovered files are fairly HUGE, unlike the originals.
So, I used GPSBabel
I tried converting a HUGE recovered gdb file to GPX format....just for laughs.
It worked. Mapsource opened the gpx file, perfect, and it was way smaller than the recovered file.
So, I tried converting a HUGE recovered gdb file to a gdb file and that worked too.
For example of size, recovered file 300,000kb converted to functional gdb 2kb.
recovered 170,000kb converted to 55kb.
Hmm, not much logic to it, but the converted files open, and my original data seems sound.
Saved the best for last.
I FOUND the entire data set that I thought I had lost!
I DID indeed back it up, to a secret folder, on an external, forgotten during panic mode...
I pursued this other stuff for personal curiosity.
Still trying to figure why I cannot get photorec to find GPX files, but I think it has something to do with UTF-8 encoding...