How to uniquely Identify a DVD?

[DVD Maniac]

I've been playing around with the VIDEO_TS.IFO file for a random selection of my collection to see how it would be possible to UNIQUELY identify the disc. I am familiar with the method used on Audio CD whereby Media Player and its rivals look up CDDB databases to identify the disc by its track lengths and positions. What is the equivilant for DVD?

In the VMGM_MAT table there are various encouraging looking fields such as -

VMG Identifier
Provider ID

But none of these appear to be a definitive and unique looking ID. Really what I am after is a code which I could use to identify that particular commercial disc on say Amazon or IMDB. Does this exist?

My second question would then be how to do this with non commercial burns of say Holiday Movies or Photo discs. Obviously there is no ID to look up here but I still want to find a way of marking the disc ID on the disc itself by editing the VIDEO_TS file. When I try to do this with the fields metnioned above IFO edit gives an error message "Item is not editable"

Any help / suggestions appreciated

[jeanl]

If you're familiar with the way they do it with audio CD, then you know they create a unique number by using the number of tracks on the CD and the lengths of the individual tracks. This works quite well for audio CDs. Now my guess is you need to do something of that kind with DVDs, except that it will be easier, there's plenty of numbers to use in there!!! The ADC tables for example (the list of all the cells in a given title set) will give you lots of material to start with, or you could use the chapter table. Or you could use the cell playback times in the PGC info tables etc etc etc... From that, you'd compile a number that would be your unique identifyer...
Jeanl

[DVD Maniac]

Hi Jeani,
That sounds like a good idea - thanks!

I am surprised then that the same approach has not been developed for commercial DVD's as for Audio CD? Maybe because its assumed that the need is not there?

So thinking about how you would achieve this -

- Use IFO edit or similar to read in a predermined set of VIDEO_TS fields which are always decimal values
- Use a predermined formula to calculate a number based on above
= Store that number somewhere

Now ideally you would want a program to automate the above process and then you could always uniquely ID a disc in your collection depending on the number that is generated. Does one exist?

It might also be useful to actually store the ID in the VIDEO_TS file (direct to the disc if its +/- RW) or if you are backing up on a +/-R. Like I said, the most obvious fields are not editable using IFO edit so not sure how this would work.

[r0lZ]

VMG Identifier: This field holds an ID that identify the file as being a valid VIDEO_TS.IFO/BUP file. Of course, it cannot be edited, or the file will not be recognized anymore by the player and reauthoring tools.

Provider ID: This field is supposed to hold the name of the producer or distributor of the DVD. It may be filled with anything you want. You cannot edit it with IfoEdit, but it's easy with PgcEdit (Utilities -> Set Provider ID). It's a text ID, so, you will need to use ASCII characters only.

I think there must be an official way to identify a comercial DVD, because my Sony is able to hold bookmarks for every DVD I have inserted at least once. I don't know what field it uses. Maybe it's a method like the one suggested by jeanl.

[2COOL]

You cannot edit it with IfoEditSure you can!
http://forum.doom9.org/showthread.php?s=&postid=415534#post415534

But, it's way easier to use PgcEdit. ;)

[spyhawk]

How 'bout use DVD-Text to uniquely identify DVD, assuming that your dvd player is able to support DVD-Text? One good discussion was here: http://www.cdr-zone.com/forum/viewtopic.php?t=1062 (http://www.cdr-zone.com/forum/viewtopic.php?t=1062)

If this is not what you're looking for, then forget what I said. ;)