How to handle two sets of bytes for matching improvements? about puremagic HOT 4 CLOSED

What we could do there is instead of matching at offset 0 and FORM we can change to the offset where the more accurate info lives and match there instead.

Don't currently have a way to do wildcards, so can't be as accurate matching both FORM and ACBM

Thanks for the info, I can work on that when I have time. If you know a source of sample files for that please share!

from puremagic.

Thanks for the samples! Added a multi-part detect.

Should be working in 1.20 https://github.com/cdgriffith/puremagic/releases/tag/1.20

from puremagic.

Nice! I've just looked at the implementation and that's way a great way to handle it, much tidier than mine. I'll test it out later on a script I have for handling converting images between formats.

For retro uses this will be handy as there are a lot of older formats like file packers that use a two part fingerprint.

from puremagic.

Instead or in addition to wildcards another option could be dual match, take our .iff sample, we could look to do...

[["464f524d","494c424d"], [0,8], "", "application/x-iff", "IFF file"],

If your code sees a list instead of a string, process both hex matches using the matching offset from the next list, if both matches, we get pretty much 100% confidence it's what we think it is. Logic is a little weirder than wildcarding but it's another possible way.

Aminet is pretty much the internet oldest resource for all things Amiga, we should be able to find pretty much all things there.

• Samples
• iff

7zip will happily unpack most of the .lha and other formats you'll find there. If you get stuck on any let me know and I'm sure I can unearth samples from somewhere.

from puremagic.