Unique Disc ID

[phileeny]

When I rip a DVD (yes I still watch and buy DVDs) with DVDs I use backup to ISO, with Blu-ray or 4k I backup to folder first then MKV later, but with the loads of discs I have there is sometimes the same film or bonus disc in special editions boxsets etc. and when the disc is inserted its name may come up the same or slightly different, now I know discs have a unique disc ID.
Is there a way to get this ID using MakeMKV now or in the future so I can avoid ripping a duplicate discs, or is there a free way to read this ID?

[dcoke22]

I'm aware of the Media Identification Code on writeable media. I'm not aware of a guaranteed unique ID on commercial pressed discs.

Couldn't you use some filename conventions or folder structure to allow for multiple versions of a movie to exist on your filesystem?

For example:
Alien (1979) - [boxset Alien Triple Pack].iso
Aliens (1986) - Special Edition - [boxset Alien Triple Pack].iso
Alien 3 (1992) - [boxset Alien Triple Pack].iso

[flojo]

... now I know discs have a unique disc ID.

No, they do not have to. In fact I remember commercial DVDs that were seemingly authored once and simply had the VOBs swapped out... same volume label, menus and everything else.

Choose a file or files that are always present on the disc and hash them. 7z is multi-platform and simple. With some basic scripting you can also use a few megabytes of video. If you can't script then just get the volume label (if any) and match the patterns '*_0.VOB' and '*.IFO'. You could match an actual VOB, but that might take a while since the bottleneck is the drive speed, not the CPU speed. But you could get the sizes of all files, that should sort of be unique.

Code: Select all

# An example:
7z h -ba -scrcSHA256 *_0.VOB *.IFO
e16f1596201850fd4a63680b27f603cb64e67176159be3d8ed78a4403fdb1700             2  VTS_1_0.VOB
c1b95499648ff119fdf2fde5807cb7c3d2cd5fb92f76f4f03692aa41659d889d             9  someting.IFO
# get filename and sizes NOTE: the 9 and 2 are because I used actual dummy files (one 9 byte and two 2 bytes)
stat -c '%s %n' *
9 someting.IFO
2 VTS_1_0.VOB
2 VTS_1_1.VOB

[christopher2222]

I've had the odd time where the mkv just goes to something like title01.mkv or something. A couple of times I've lost a few titles without noticing they were being overwritten. Just have to be aware.

[phileeny]

Thanks for the info.
When I put a disc in to DVD Profiler to database my collection it gives me a disc ID "C42A5E66C78593DF [MARVEL_STUDIOS_GUARDIANS_3]"
Or Mars Attacks my first DVD ever purchased "9C68E31EA5ED2F0A" I don't know where this "hash" is generated.

[dcoke22]

http://www.invelos.com/Forums.aspx?task=viewtopic&topicID=926221

It seems, according to that thread, that DVD Profiler depends on something in Windows to generate a disc ID for DVDs. That thread is mostly about how a version of Windows 10 apparently changed how that was calculated so the new version of Windows generated a different disc ID for the same disc.

Out of curiosity, why are you trying to get this 'disc ID' hash?

[flojo]

http://www.invelos.com/Forums.aspx?task=viewtopic&topicID=926221

It seems, according to that thread, that DVD Profiler depends on something in Windows to generate a disc ID for DVDs. That thread is mostly about how a version of Windows 10 apparently changed how that was calculated so the new version of Windows generated a different disc ID for the same disc.

Out of curiosity, why are you trying to get this 'disc ID' hash?

It seems that AnyDVD's decryption proxy (for CSS) was on when one hash was generated, then off when another hash was generated. To me it seems like you should hash whatever is on the filesystem (UDF in this case), unless there's something stopping that.

There's a post stating they're getting different hashes from different software, which is unsurprising.

http://www.invelos.com/Forums.aspx?task ... 5#M3447185