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Unique Disc Identifier for DVD-R discs

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While making backup copies of old DVD-R discs I made a point of reading the RMD (Recording Management Data) sectors. For each disc I copied the burner make/model/serial, disc MID, and the UID (Unique Disc Identifier) into a text file. Since the UID is supposed to contain the date and time that the disc was burned, I decided to set the modified date for that text file to match the disc's burn date and time. This makes it easy to search and sort disc images by their burn dates which can be quite handy.

 

Most of the discs burned with various versions of Nero have the correct date+time in the UID. This is important since Nero burned the layout creation date, not the burn date, to the file system (at least for ISO+Joliet layouts). Some versions of Nero had problems with the UID though. One version I used made the month in the UID one month before the actual burn date. A later version unconditionally set the date and time as September 18th, 2003 @ 19:00:00.

 

For all of the DVD-R discs that I burned with ImgBurn, the date and time fields of the UID are all set to 0. This is generally fine since ImgBurn writes the burn date into the file system. However, when burning a disc from an image there is no record of the burn date and time since only the original dates/times in the file system are placed onto the disc.

 

Is there currently any way to use ImgBurn to set the contents of the UID? I'm interested in being able to set the burn date and time as defined in the MMC specs. Additionally, I'm interested in being able to set the UID to other values such as the date/time stored in an image's file system and the date/time stored in a backup of RMD sectors (16-sector / 32KB block).

 

Thanks ahead for your reponse and thoughts on this.

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No, ImgBurn can't do that I'm afraid.

 

ImgBurn doesn't write the burn date in the file system either, only the creation date. Of course if you build and burn straight away or burn on the fly, that's close enough.

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Thank you very much for responding so quickly. Out of curiosity, is there any particular reason that ImgBurn doesn't write the date and time into the UID? The MMC specs suggest that setting the date properly may have an impact on OPC results. Quoting MMC-4 rev. 5a below:

 

This time stamp data may also be used in OPC related field in RMD Field 1 and may help the judgement to do OPC

 

This may have changed at some point since MMC-5 and MMC-6 have removed this text.

 

ImgBurn doesn't write the burn date in the file system either, only the creation date. Of course if you build and burn straight away or burn on the fly, that's close enough.

 

My understanding is that the volume creation date (or for UDF the "recording date and time" field) is part of the file system. The date and time that the burning process begins certainly seems to be what ImgBurn stores there. I have layouts from years ago that are still used today. It makes a big difference that ImgBurn burns the current date and time for each new disc instead of the very inaccurate creation date of the layout/project like Nero did.

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It's just not something I've ever thought about making it do.

 

There are no dates stored in ImgBurn's 'build mode' project files, so date fields always get filled out with the current one.

 

No attempt is made to fill anything out with the actual burn date, hence why you've seen it doesn't get changed / updated when burning a prebuilt ISO file.

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There are no dates stored in ImgBurn's 'build mode' project files, so date fields always get filled out with the current one.

 

Thank you very much for the clarification on this and for taking the time to answer all of my questions. :)

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I can add an option that makes the program set and update the timestamp via the 'send disc structure' command - as per the MMC specs.

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I've done it today by adding a 'Disc Timestamp' option within the Settings on the Write tab / Page 2. That option can be set to 'None', 'System' or 'Custom'.

 

It still defaults to 'None' though, whereby the command isn't issued.

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