We deliver a corresponding MD5 checksum (aka "hash") file with every
file (BWF, WAVE, MP3, scanned metadata, etc.) that we deliver to our
clients. The delivery and use of MD5 checksums should be considered
archival "best practice", as it is the only way to be absolutely sure
that a digital file has not been corrupted over time, or that there
were no errors when copying or moving a digital file.
If you are on Windows...
We tested the many, MANY checksum generators available as freeware
and shareware, and we finally settled on "Fastsum" (www.fastsum.com).
It has a VERY professional user interface which allows you to
either generate checksums for batches of files, or validate batches
of files. We have Fastsum loaded on all of our capture and editing
stations, and use it many times daily. It has performed flawlessly
with no quirks or bugs, and the Fastsum customer service (via email)
is very responsive.
Fastsum is highly configurable, from generating individual checksum
files for every target file (what you want to do), to generating a
single file that contains individual checksums for every file (this
is the default setting).
Initially, I was disappointed that Fastsum didn't have a means to
call it from another program. However, the Fastsum user interface
makes things so simple that this has not been a workflow issue, even
when processing hundreds of hours of audio a week. Of course, if
you want a checksum generator that can be incorporated into your
software automation, there are plenty of options (we haven't done
a systematic evaluation of these).
The free version of Fastsum (and I think the home version, too) adds
some text advertising to each MD5 checksum file. The "Enterprise"
version (all of $25 for one license) allows you to turn off the
advertising. I consider this money well spent (we purchased one of
the multi-user license packages). Usual disclaimer: we have no
relationship with Fastsum and do not benefit in any way from the
sales of Fastsum software.
Slightly off topic... we are experimenting with running an MD5
checksum on just the PCM portion of the WAVE/BWF file, so that we
can edit the WAVE-RIFF and bext chunks and insure that there
was no corruption to the PCM audio in the process.
The Audio Archive, Inc.
mailto:[log in to unmask]
From: Association for Recorded Sound Discussion List
[mailto:[log in to unmask]]On Behalf Of Richard L. Hess
Sent: Saturday, January 19, 2008 9:05 AM
To: [log in to unmask]
Subject: [ARSCLIST] MD5 Hash Generators
I am starting to generate an MD5 hash of the files that I deliver by
ftp and was wondering which MD5 hash generators are popular.
I found a pretty neet one-file-at-a-time applet that will generate a
companion ".md5" file which is good for my workflow. www.drnaylor.co.uk
I would like a batch generator that would place each hash into a
separate text file with the complete filename and the extension md5 added.
Of course, I'd prefer freeware as I don't think this is an
Richard L. Hess email: [log in to unmask]
Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.