I imagine it is some kind of comparison between the original files and the files that have been burned on the disc, but does anybody know how it is really done at a low level?
I mean, does it create a hash of the source and destination content and then compares them? If it is so, does it store the hash of the burned content in RAM? Or does it save it in a temporary file on the hard drive? Is there a log file of what is going on?
Just curious to know exactly how this feature works 🙂 And I am referring to Windows Image Burner.
Best Answer
Check out these MSDN pages on windows API for the
IBurnVerification
interface, and theIMAPI_BURN_VERIFICATION_LEVEL
enum.For data disks, it looks like in quick mode it doesn't checksum the entire disk, just a selection of sectors. It then makes sure that the API calls
READ_DISC_INFO
andREAD_TRACK_INFO
succeed against the new disk.For full verification, it performs the above checks, and then does a full checksum on the last session on the new disk, against a checksum computed on the memory stream being burned. The checksums have to be stored in ram, but they are likely short lived values. Note that the comparison is against the disk image in RAM, not the source media itself, so if the source data did not read correctly, it will be written incorrectly. Verification will not detect this.
For music disks, it focuses on checking
READ_TRACK_INFO
and the disk Table of Contents, but does not perform a Checksum calculation. There is no full verification mode for music.