Cannot Seem to make Custom Signatures Work

Using PhotoRec to recover lost data
Forum rules
When asking for technical support:
- Search for posts on the same topic before posting a new question.
- Give clear, specific information in the title of your post.
- Include as many details as you can, MOST POSTS WILL GET ONLY ONE OR TWO ANSWERS.
- Post a follow up with a "Thank you" or "This worked!"
- When you learn something, use that knowledge to HELP ANOTHER USER LATER.
Before posting, please read https://www.cgsecurity.org/testdisk.pdf
Locked
Message
Author
Jordanis
Posts: 1
Joined: 09 Jun 2012, 14:32

Cannot Seem to make Custom Signatures Work

#1 Post by Jordanis »

I'm trying to recover some .3dm Rhino 3D model files. I ran a hexdump on a sample, which returns

Code: Select all

00000000- 33 44 20 47  65 6F 6D 65  74 72 79 20  46 69 6C 65 [3D Geometry File]
00000001- 20 46 6F 72  6D 61 74 20  20 20 20 20  20 20 20 33 [ Format        3]
I have therefore created a photorec.sig file in the folder from which photorec is running (on Windows). Currently, its contents are

Code: Select all

3dm 0 0x33 0x44 0x20 0x47 0x65 0x6F 0x6D 0x65
I have also attempted

Code: Select all

3dm 0 0x33442047656F6D65
Plus variations in length on that, as well as

Code: Select all

3dm 0 "3D Geometry File"
In all cases, fidentify has been unable to identify the sample file. Given that I am attempting to identify the same file as I dumped to get the signature, I can only conclude that I am either mis-constructing the photorec.sig file, or PhotoRec is for some reason ignoring the photorec.sig file. In either case, I would appreciate any help to resolve the issue. Thank you!

User avatar
cgrenier
Site Admin
Posts: 5432
Joined: 18 Feb 2012, 15:08
Location: Le Perreux Sur Marne, France
Contact:

Re: Cannot Seem to make Custom Signatures Work

#2 Post by cgrenier »

Have you try your photorec.sig file with latest PhotoRec 6.14-WIP ?
Is it a true ascii text file ? It must not beging by EF BB BF (UTF-8 Byte Order Mark) or FF FE (UTF-16 LE).

User avatar
eddie
Posts: 1
Joined: 20 Nov 2012, 19:38

Re: Cannot Seem to make Custom Signatures Work

#3 Post by eddie »

Hi Jordanis,
Try with:
3dm 1 "3D Geometry File"
because your string start at 1, at 0 there is [
or:
3dm 0 0x33442047656F6D657472792046696C65
using all first row in hex.

Good luck,
l'eddie

Locked