| Other Useful Information |
Do take into consideration that the DVD+R/+RW 'Media code'-block may contain drive modified values when the ADIP is read through the use of Method 2 (= Copy of ADIP). This means that the ADIP information shown in the hex dump is not 100% identical to the original ADIP on the disc (Method 1 is required in order to retrieve the original unmodified ADIP). 'DVD Identifier' will still report the correct disc parameters because it will compensate for this problem by using additional techniques to retrieve all the needed information. Following values are likely susceptible for modification by the drive : Book type, Last physical sector of data zone (only for DVD+R, not for DVD+RW) and the Extended information indicators. Basically the entire range starting with byte 0 up to and including byte 18 (=0x12) may contain modified data (shown in red below).
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** WARNING : Format 11h (Method 1) Is Recommended
ADIP Retrieval Method |
Some DVD-R writers are able to write at 2x on selected 1x DVD-R media (i.e. discs that only contain 1x write strategy parameters), but this depends on the drive you are using and its firmware. If a DVD-R disc is inserted with no 2x write strategy parameters then this 2x write speed will be displayed surrounded by brackets. If write strategy information regarding 2x is present on the disc then the 2x speed is displayed without brackets. So, the reported recording speeds can look like [1x - (2x)] or [1x - 2x] depending on the write strategy parameters that are present on the disc.
When the 'Media code'-block is retrieved from the disc, the drive will always insert a 4-byte header in front of the 'Media code'-block. Since this header is totally unrelated to the disc and therefore contains no useful information it is by default removed by 'DVD Identifier'. If desired, you can clear the 'Discard 4-Byte header'-checkbox in the 'Advanced'-menu so that the header is included anyway. This option is offered solely for layout purposes. Since this header contains no relevant information regarding the disc it is always cleared to zero before it is displayed.
When the 4-byte header (shown in red) is inserted in front of the 'Media code'-block it will result in a slightly different looking hex dump :
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** INFO : 4-Byte Header Preceding 'Media
Code'-Block Discarded ** INFO : 4-Byte Header Preceding 'Media
Code'-Block Present But Cleared |
| Known Issues And Limitations |
On DVD+R/+RW the blank disc capacity will only be reported when the drive supports ADIP retrieval Method 1. No limitations exist regarding the blank disc capacity when handling DVD-R/-RW discs.
When dealing with high-speed DVD-R discs many drives will only report a partial 'media code'-block. This makes it impossible for 'DVD Identifier' to determine all of the disc's certified recording speeds since not all of the disc's write strategy information is accessible. So, even though 8x/16x detection code is in-place many drives do not report sufficient 'write strategy'-information to actually make speed detection work.
Note that you will still always get the 8x/16x write speed descriptors (which are shown in the 'Drive capabilities'-tab) if your drive is capable of writing to the disc at these speeds. But do keep in mind that many drives require an empty disc in order to correctly report all write speed descriptors.