Technical Information

DVD manufacturing information is already pre-recorded on empty media. This manufacturing information contains information such as the disc type, manufacturer identification and the recording speeds supported by the disc. How this information is retrieved depends on several factors (such as the disc type) and is described below :

With DVD+R/+RW the pre-recorded information is carried by something that is called ADIP (ADdress In Pre-groove). Depending on the circumstances, 'DVD Identifier' employs two different techniques for retrieving the ADIP  :

DVD+R/+RW : ADIP retrieval method 1 (Original ADIP - ADIP information)

This is the preferred method for ADIP retrieval since it obtains the original ADIP from the disc. However, to retrieve the ADIP in this manner a command is used which is only relatively recently introduced in the Multimedia command specification (MMC-4 revision 2a, dated June 9th 2003). As a consequence the number of drives that support this command will initially be relatively limited. Nevertheless, all new drives will support this command and older drives will likely include future support for this command through firmware upgrades. For example, the Ricoh MP-5125A (a very popular drive which is also shipped by companies such as Hewlett-Packard and Philips) does not support this command with firmware 1.51. But once the firmware is upgraded to 1.64, ADIP retrieval using method 1 is supported.

If your drive does not support method 1 an attempt will be made to retrieve the ADIP by using method 2.

DVD+R/+RW : ADIP retrieval method 2 (Copy of ADIP - Physical format information)

While method 1 also works with empty discs, method 2 requires the use of already written discs (either a DVD+R with closed session or a DVD+RW that is at least partially formatted). Every written disc contains a copy of the disc's original ADIP and with method 2 this copy will be read out instead of the original ADIP. Since reading this copy of the ADIP is done by a command which is supported by nearly all drives no significant drive compatibility issues are expected here. Do note that there are in fact some drives that can still handle method 2 even with empty discs.

DVD+R/+RW Medium Detected. Starting Identification... ** Initiating ADIP Retrieval Method 2 (Copy Of ADIP) ADIP Read Method 2 Completed Without Errors

Method 2 fails on most drives when an empty disc is used :

DVD+R/+RW Medium Detected. Starting Identification... ** Initiating ADIP Retrieval Method 2 (Copy Of ADIP) ADIP Read M2 Failed : Illegal request - Invalid field in CDB [05/24/00] ADIP Read Method 2 Requires A Written DVD+R/+RW Disc

With DVD-R/-RW the pre-recorded information is stored in LPPs (Land Pre-Pits). On DVD-R/-RW only a single method is available and needed for retrieving this information.

DVD-R/-RW : LPP retrieval (Pre-recorded information from DVD-R/-RW Lead-in)

This method of LPP retrieval should work on any DVD-R/-RW disc regardless of the fact whether the disc is already written or not. LPP retrieval should be supported by nearly all DVD-R/-RW writers.

DVD-R/-RW Medium Detected. Starting Identification... ** Initiating LPP Retrieval LPP Read Completed Without Errors