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View Full Version : MD5/Fingerprint How to make and examine?


mattstrike
2005-10-31, 08:30 PM
Hi,
This question has been asked a lot I bet, but I can't seem to find the exact answer I am looking for...

Basically, I have a lot of torrents I have downloaded over the past week. Hard drive is full. So I have to back these FLAC and SHN files to DVD-R, but I know I need to create an MD5 to check the files, but I am unsure of the order or what I am supposed to do. Can some one refer me to an answer or explain it to me?

I know nothing. Nothing... about this checksum business. So the more detailed the better. I really appreciate it. :confused: :confused:

U2Lynne
2005-10-31, 09:58 PM
Hi Matt,

First off, you shouldn't have to make md5s/fingerprints/checksums (whatever you want to call them) because the shows should come with them. They either have an extension of md5, ffp, or st5. Usually you can double click on it and it will check the files for you.

What program do you have installed to check these with? Do you have Traders' Little Helper? Or md5summer? Or mkwACT? Or nothing yet?

mattstrike
2005-10-31, 10:17 PM
Oh sorry - I should have told you all what OS I am running...

Mac OSX 10.4.3
I use BitTorrent 4.something (the latest, not the beta)
and xAct 1.5b3

Some of the flacs didn't come with them (I got them off of another site)... any way, what do I do with the ones I have?

Actually, I will check on that "not having them thing".

Nope a few don't have them, and some have .LOG files or fingerprint txt files. Are these usable?

Thanks Lynne (should I put the U2 in front>?)

U2Lynne
2005-10-31, 10:25 PM
OK, first off xACT is everything you really need (for making/decoding the files).

Shn files should all come with either md5 or st5 files. Flac files *may* come with either ffp or md5 files. However, any of these could be disguised as being 'md5.txt' or 'ffp.txt' or whatever. So, look at those txt files closely. I have a guide I wrote about a year ago for md5 and ffps using xACT. Take a look at that and see if you have other questions: http://u2lynne.sandsmuseum.com/checksums.html

LOG files are using from the extracting software (EAC or xACT).

mattstrike
2005-10-31, 11:27 PM
Thanks Lynne.
I think I only have one more question:
Do I verify the flac and shn files before I back them up and that's it, and/or do verify them again once they are burned to a DVD-R? If so, how do I do that? By running the md5 or ffp from the DVD?

Sorry to be such a lunkhead about this...
I appreciate the help.

U2Lynne
2005-10-31, 11:34 PM
When I was first backing stuff up and didn't know if my media was good or my burner was good, I checked the files before I burned them and after I burned them. Now, I randomly check them after the burn.

As for how to do it, if you burn the files/folders exactly how you got them, you should be able to double click the md5/ffp/sd5 files on the DVD and it should verify them on the DVD.

mattstrike
2005-11-01, 12:16 AM
Thanks again! Backups commencing...

AAR.oner
2005-11-01, 10:33 AM
Matt...

one thing more, when creating a checksum for a show that was seeded without one, i usually make a note in the info text file stating such...for instance, i usually put something like:

"Show seeded w/ no checksum. Checksum created "in post" on [date]"

this is helpful down the road when comparing sources or copies.

mattstrike
2005-11-01, 11:23 AM
Sure, thanks for the advice....
BTW - your sig file is a riot (which is prolly why it's yr sig file!)

mattstrike
2005-11-01, 12:20 PM
Hopefully this will be the last question regarding this subject:

What happens if the checksum finds an error? Is there anything you can do about it?

For example:
I just checked the md5 file for Disc 4 in the Jewels and Binoculars 1966 (26 cd set) - which I got here.

This is the error I got from xACT (checking the file(s) that I b/u'd to DVD-R):
d04.md5: FAILED
Track01.flac: OK
Track02.flac: OK
Track03.flac: OK
Track04.flac: OK
Track05.flac: OK
Track06.flac: OK
Track07.flac: OK
Track08.flac: OK
md5sum: WARNING: 1 of 9 computed checksums did NOT match

This Disc only has 8 tracks, so what's the 9th checksum refer to?
I get the same error when I check the file on my HD.

Five
2005-11-01, 12:36 PM
open the .md5 using notepad and see what the 9th checksum is supposed to be pointing to.

the best way to test FLACs is still to dump them in FLAC frontend or Trader's Little Helper and run "test" mode.

Also check the artwork, etc. could it be there is supposed to be a 9th track which is missing?

jazzbo
2005-11-01, 03:13 PM
Hopefully this will be the last question regarding this subject:

What happens if the checksum finds an error? Is there anything you can do about it?

For example:
I just checked the md5 file for Disc 4 in the Jewels and Binoculars 1966 (26 cd set) - which I got here.

This is the error I got from xACT (checking the file(s) that I b/u'd to DVD-R):
d04.md5: FAILED
Track01.flac: OK
Track02.flac: OK
Track03.flac: OK
Track04.flac: OK
Track05.flac: OK
Track06.flac: OK
Track07.flac: OK
Track08.flac: OK
md5sum: WARNING: 1 of 9 computed checksums did NOT match

This Disc only has 8 tracks, so what's the 9th checksum refer to?
I get the same error when I check the file on my HD.

The filename before the colon indicates what it is checking. Whoever created this md5 file also included the md5 file itself among the files to generate a md5 for. This is more or less impossible -- or extremely improbable -- to be able to generate a md5 for a file and then output the md5 of the final file back into the original md5 itself.

More or less you can just ignore any checks against a md5 file.

kuschel
2005-11-05, 08:52 AM
the best way to test FLACs is still to dump them in FLAC frontend or Trader's Little Helper and run "test" mode.



is there something comparable for shn?

or well.. if I decode the shn file to *.wav and then to flac.. will it show me the failure if there was one on the original shn file?

AAR.oner
2005-11-05, 09:12 AM
is there something comparable for shn?

or well.. if I decode the shn file to *.wav and then to flac.. will it show me the failure if there was one on the original shn file?
if you decode a shn file to wav, and then re-encode to flac, the orig checksum won't verify...you'll need to create a new st5 or ffp checksum on the flac files...but save the orig checksum and include it when trading, this'll alow people to crossreference versions down the road.

kuschel
2005-11-05, 02:49 PM
if you decode a shn file to wav, and then re-encode to flac, the orig checksum won't verify...you'll need to create a new st5 or ffp checksum on the flac files...but save the orig checksum and include it when trading, this'll alow people to crossreference versions down the road.

yeah.. i just wanted to know if it's possible to check shn files somehow if I don't have a md5 anymore..

on flac files i can still test them with flac frontend.. if i got that right..

TheMamba
2005-11-05, 03:10 PM
yeah.. i just wanted to know if it's possible to check shn files somehow if I don't have a md5 anymore..

on flac files i can still test them with flac frontend.. if i got that right..

You're correct. And, that's one of the many advantages of FLAC over SHN.

What you could do is post over in the Show Discussion section:

http://www.thetradersden.org/forums/forumdisplay.php?f=51

Create a new post and see if anyone else has that show already, if they have the MD5, they can post it for you.

kuschel
2005-11-05, 03:30 PM
thanks a lot..