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Can't detect a disk's second layer except in a real player

Posted: Sun Feb 16, 2025 12:22 am
by BlackChakram
So I've been ripping my Stargate SG-1 DVDs and have discovered that I'm getting a problem on only a handful of random disks that's leaving me stymied.

All the disks are dual layer. However, even though MakeMKV can report that there are two layers (PTP), it gives the disk capacity at only 3.42 Gb. Each episode rips at about 1.7 GB so I knew something was wrong as that only accounts for 2 episodes out of the 4 on each disk. Sure enough, even if I try to open the disks manually, I get errors on the 3rd and 4th episode of each disk. "Title {x} was skipped due to navigation error".

I then tried ImgBurn. Verifying the disk, I see right away that Layer 0 reports 100% sectors while Layer 1 says 0%.

I then tried DVD Decrypter. It definitely sees the disk capacity at over 7 GB and can see all the video_ts files, but fails when ripping.

Regardless of which program I use, I get errors akin to the PC trying to read sectors it thinks are out of bounds.

I began to suspect damage to the disk, so as a last resort, I dug out my old LG Blu-Ray player, connected it to the TV and played the disk. WORKS PERFECTLY. All 4 episodes.

So has anyone seen anything like this? It seems to be copy protection that fools every program into not understanding how to even access the second layer....

I've added a dump from MakeMKV

Code: Select all

Using LibreDrive mode (v06.3 id=7FA2657C7667)
Using direct disc access mode
Error 'Internal error - Input parameter is incorrect (489)' occurred while reading '/VIDEO_TS/VTS_02_1.VOB' at offset '0'
Error 'Internal error - Input parameter is incorrect (489)' occurred while reading '/VIDEO_TS/VTS_02_1.VOB' at offset '0'
Error 'Internal error - Input parameter is incorrect (489)' occurred while reading '/VIDEO_TS/VTS_03_1.VOB' at offset '0'
Error 'Internal error - Input parameter is incorrect (489)' occurred while reading '/VIDEO_TS/VTS_03_1.VOB' at offset '0'
Cells 1-1 were removed from title start
Title #1 was added (5 cell(s), 0:43:56)
Cells 1-1 were removed from title start
Title #2 was added (5 cell(s), 0:43:53)
Cells 1-2 were removed from title start
Title #3 declared length is 0:34:52 while its real length is 0:00:00 - assuming fake title
Fake cells occupy 32% of the title - assuming fake title
Title #5 in broken titleset was skipped
Title #6 in broken titleset was skipped
Title #7 in broken titleset was skipped
Title #8 in broken titleset was skipped
Title #9 in broken titleset was skipped
Operation successfully completed

Re: Can't detect a disk's second layer except in a real player

Posted: Wed Feb 19, 2025 6:07 am
by dcoke22
Properly formatted DVD-Video uses Opposite Track Path (OTP). Only DVD-ROMS use Parallel Track Path (PTP).

If you really have dual layer PTP DVDs that are supposedly Stargate SG-1, I suspect they're counterfeit. I would expect most ripping software to expect a dual layer DVD to be OTP. Consequently, when things switch to the second layer, the ripper would be very confused since the second layer is backwards from what it would expect.