can't decrypt CPRM only with Liteon

[kner]

8.0.1.5 can't decrypt CPRM only with Liteon LH-20A1S and LH-20A1P.
(8.0.1.5 can decrypt AVCREC and BDAV.)

I unintalled 8.0.1.5 and reinstalled 8.0.0.8 again.
8.0.0.8 was able to decrpyt CPRM with LH-20A1S and LH-20A1P.

cprmgetkey 0.21.exe was able to get cprmkey with LH-20A1S.
The drive letter of LH-20A1S is G in the log.
So diffenent to the previous my mistake(http://forum.dvdfab.com/showpost.php...3&postcount=10),
8.0.1.5 has certain problems with respest to CPRM.

Passkey must implement all versions of cprmgetkey.exe
(cprmgetkey 021,022,031,036,037,038,041).
The reason is as follow.
cprmgetkey 021 and 022 can decrypt cprm with Liteon LH-20A1S,LH-20A1P,
but can't do so with Plextor PX-716A.
On the other hand,cprmgetkey041.exe can decypt cprm with Plextor PX-716A
,but can't do so with Liteon LH-20A1S,LH-20A1P.
(See http://wiki.nothing.sh/page/CPRM%A4%...4%E1#navigator ,in Japanese)

That is to say,we must use all versions of cprmgetkey.exe in order to be able to decrypt CPRM with all DVD drives.

[DarthCopier]

8.0.1.5 can't decrypt CPRM only with Liteon LH-20A1S and LH-20A1P.
(8.0.1.5 can decrypt AVCREC and BDAV.)

I unintalled 8.0.1.5 and reinstalled 8.0.0.8 again.
8.0.0.8 was able to decrpyt CPRM with LH-20A1S and LH-20A1P.

cprmgetkey 0.21.exe was able to get cprmkey with LH-20A1S.
The drive letter of LH-20A1S is G in the log.
So diffenent to the previous my mistake(http://forum.dvdfab.com/showpost.php...3&postcount=10),
8.0.1.5 has certain problems with respest to CPRM.

Passkey must implement all versions of cprmgetkey.exe
(cprmgetkey 021,022,031,036,037,038,041).
The reason is as follow.
cprmgetkey 021 and 022 can decrypt cprm with Liteon LH-20A1S,LH-20A1P,
but can't do so with Plextor PX-716A.
On the other hand,cprmgetkey041.exe can decypt cprm with Plextor PX-716A
,but can't do so with Liteon LH-20A1S,LH-20A1P.
(See http://wiki.nothing.sh/page/CPRM%A4%...4%E1#navigator ,in Japanese)

That is to say,we must use all versions of cprmgetkey.exe in order to be able to decrypt CPRM with all DVD drives.

Interesting comments re CPRM and CPPM type protections, but I fail to see where these apply to our specific situation, as the major use of this type of protection seems to be applied to things like removable media (USB Flash Drives, etc.).

Have never come across a DVD (at least here in N.A.) that requires any attention at all be paid to CPRM, and any CDs protected by such seem to not be a problem by the copying programs available...

Is this a major problem in your neck of the woods??

DC

[fengtao]

It's strange, we didn't change any code related to CPRM.

Could you please post the internal log for the two drives?

Thanks.

[kner]

I attached two internal log files.
Another PC has a LITEON LH-20A1P DVD Drive(Drive letter is D).

I uninstalled and reinstalled various veisions of Passkey many times.
I found the following fact.
8.0.0.8 and 8.0.1.1 can decrypt CPRM with LITEON LH-20A1P and LH-20A1S.
But 8.0.1.3 and 8.0.1.5 can't do so.

Needless to say,8.0.0.8,8.0.1.1,8.0.1.3,8.0.1.5 can decrypt CPRM
with other DVD Drives except LITEON.

There may be some differences between 8.0.1.1 and 8.0.1.3 with respect to CPRM.

[DarthCopier]

I attached two internal log files.
Another PC has a LITEON LH-20A1P DVD Drive(Drive letter is D).

I uninstalled and reinstalled various veisions of Passkey many times.
I found the following fact.
8.0.0.8 and 8.0.1.1 can decrypt CPRM with LITEON LH-20A1P and LH-20A1S.
But 8.0.1.3 and 8.0.1.5 can't do so.

Needless to say,8.0.0.8,8.0.1.1,8.0.1.3,8.0.1.5 can decrypt CPRM
with other DVD Drives except LITEON.

There may be some differences between 8.0.1.1 and 8.0.1.3 with respect to CPRM.

Finally... the light dawns!!

I looked at your Passkey logs, and was very surprised to see that the DVDs you're working with are DVD-VR discs.

The VR spec was written to cover Video Recorders, such as cameras or Playback machines that can also perform the Write function.

This spec is NOT DVD compliant, as instead of the normal VOB files we are used to seeing, VR files are contained in a VRO container, and the internal streams, which in DVD compliant VOB containers, must be MPEG streams, the contents of the VRO containers is usually not MPEG streams.

Playback is usually possible in the device that did the recording, but usually won't play at all in a set-top player, and will only play on a computer set up to decode the VR format.

DVDFab (and Passkey) are pretty much useless for this format (and pretty much un-necessary), as the recording devices don't encode any copy protection (CPRM or any other) while or after the recording is finished, unless your manual for the device is telling you different.

Not sure where you latched onto the idea that CPRM (or its brother, CPPM) are involved, but I think the major problem here is lack of different format compatibilty, rather than any particular copy protection scheme.

DC

[fengtao]

Hi DC,

Passkey supports CPRM on DVD-VR disc, DVDFab supports it too but cannot open DVD-VR disc since the data structure is not supported yet.

Best Regards,
Fengtao