CPRM Discussion Thread

Thankyou Gogela, reading from your Smilies, i understand
my (short) message is understand, i hope many will follow,
I think the CPRM issue is very important and i think people
should be aware of this, but i’m affraid CPRM already slipped
in a lot of homes, without people knowing this, it happend
to me too. :a

Well, since this feature is probably firmware-dependent, isn’t it better to specify the firmware version too? Could be that a non-CPRM drive becomes CPRM-aware with a firmware update (I doubt that the reverse can happen)…


Yes, you’re right, but i guess no manufacturer will
build “it” in, and then later disable it in it’s firmware,
(If it’s not one and the same)
costs aspects i guess, but yes, you should ask this question,
because i guess downgrading the firmware in the drive is not
possible in most cases! only a new and hacked firmware can do this.
Also, CPRM is mostly used on the “minus” > -R -RW & -RAM media,
and it is “proposed” :a to be a feature of the ATA specs, so some of the features could be used on Hard-Disks, CPRM has always been a standard feature of the -RAM DVD media…

You are completly right ! so from now on: Also the firmware
version of the drive should be listed with the drive,
this could also prevent conflicts i guess.
I see you’re the moderator, so you have my permission to add
this to my initial post.

Thankyou chas0039
its only used on minusR media, so maybe it’s not such a disaster as i thougt it would be…

I am missing something. How can this only apply to -R media if you say it is on a DVD-Video?

I am aware of the potential inclusion in on air broadcasts and the shut down of the manditory hardware requirement last Summer, but I have yet to see this on a pressed DVD.

BTW, most of the drives I listed above were using codeguy’s firmware or L&D’s so I skipped listing it. The interesting question will be if it is firmware dependant, will it be removable.

The minus R media is according to the approved dvd “rules”
of the DVD consortium or something like that,
and has also the CPRM rules in it (specs. minus media -RAM also)
plus R media does not support CPRM, so best bet is to read
minus R media with drive that has only plus R specs. (old drive) or licenced software, that controls the CPRM functions, in CPRM compatible drive,
I recently installed the 1.02 fw. in my 740 Plextor drive,
PlextoolsProXL can now read a CPRM protected disc, but Windows can’t, when clicked up on it still asks for a disk,
While PlextoolsProXL already made an image of it,
and a disc burned of this image, is still not seen by Windows, go figure…

And why do you think this protocol will show up on pressed DVDs?

Then it’s called CPPM P=pressed CPRM R=recordable

something to read:


Also, the protocol isn’t on the disc, it’s in the drive, the operating system of the hardware itself, reads the tags/flags
on the disc.
So a drive without the CPPM/CPRM mechanism, can also read/play the disc, but for now, i don’t know, if you can play these files, once you have copied them onto other media.

Say, is it your signature, or are you just glad to see me ? :rolleyes:

Sorry, VH, for this one, i couldn’t resist it, thanks for listing your drive(s) CPRM specs.

How do you mean?


Man… I think I’m about ready to give up. CPRM is pretty damn effective… I think if it’s ever going to be defeated, the app will probably have to have firmware countermeasures for any drives that support it, native mechinisms for removing CPRM from the media you want to back up, AND a virtual CPRM server on the client machine. That’s a LOT of programming.

The only comfort is, that only minus R media is supported by CPRM, CPPM is more a pain in the… neck.

I now tried a drive that is also CPRM compatible, it allows me to “see” the disc (in Windows) that came out of my dvd standalone recorder, (i recorded ClassicFMTV which has the CPRM tag up obviously) so i copied the files onto my PC’s hd, from there i can play those files! when i put these (the VIDEO_TS map) onto a dvd+r disc with this drive, (Plextools video project) this disc becomes again invisible for windows and unplayable on any player only Plextools (ProXL) can make the contents visible, (map & files)
I guess an old drive, before the minus R media introduction, (not CPRM compatible) will give no problems,
if it can play this disc…

And have you ever seen any pressed disc DVD with this flag? As I said, I have never encountered a disc which indicated CPPM or CPRM. I assume if I had, it would have not played on one or the other of my drives but I am still not sure if CPRM being checked is good or bad. Also, just because CPRM is checked does that mean anything in relation to CPPM?

Sorry to be so obtuse, but I just have never seen this protection related in any way to pressed DVDs in any source.

Well i found some threads, one is also DVD Video Madagascar, also a typical diagnostic is: original plays in your standalone livingroom dvd player, but not in your PC,
or the copy does play in your PC but not in the standalone,
It’s a long chain of factors: (old) dvd reader, the DVD media (only use plus type) and the burner (should be one of the pre minus dvd recordable type)

I have to correct something i posted earlier,
Somehow, a disc recorded on a -R -RW (only) dvd video recorder has some keys “locked” onto the unique ID of that
(first recording) disc i guess, if you could read the .VOB’s
in a other CPRM drive, (but has some functions of CPRM switched off i guess) the new dvd disc burned with these files , wil not play in a standalone DVD player, although the files played on the PC

In short: it all is very tricky i’m afraid all new drives have the CPRM feature but only for minus media ,
This protection on pressed media (CPPM) is a different story, and i hope “plus” recordable media will block this function… “the knife cuts both ways” i guess, if they want to sell media and hardware…

Please use this thread to discuss CPRM.

I hope this structure of the "thread"doesn’t become too complicated…the subject itself is already tricky to comprehend (for me too)
I guess the protection functions CPPM and CPRM work hand in hand with eachother I don’t know yet how far the CPPM protection is having it’s influence, also on plus media ?
CPRM seems to have it’s reach only over minus media,
i guess because it’s the media that mostly complies according
to the original DVD video “book” specifications aka DVD consortium.
Using PlextoolsProXL 3.07:
With the PX-740 from Plextor, with the 1.01 firmware,
some information can be read, from a disc recorded in DVD video-recorder, that only can use -R and -RW media for recording, with the 1.02 firmware in the PX-740 the drive is still CPRM compatible but now it can read the complete DVD video disc, and make an image to make multiple disc copies from, but all these discs are still not seen by the MS Windows Operating System.

btw. trying to make a disc of the image using a +R type of media, fails…

btw2. The CPRM function is also designed to work on SecureDigital memory cards, or transferal over a Firewire or iLink connection, also the protocol is ATA friendly :frowning: but the designers say this will not be used as such…?
You can do a (Goolge) search for your self on the CPRM subject, but you will not get happy doing this :frowning:
Old read and burn hardware seem to be the most safe option to defeat CPPM/CPRM.
The hardware Manufacturer is free to build (or not) in this CPPM/CPRM function, unlike the MacroVision protection,
which looks much the same, in it’s mechanics…

Sorry… my first post has been placed in the “read first” thread by mistake…

This issue seems quite important to me. I’m a french freelance journalist and a reader alerted me on a problem with CPRM.
I’ve just posted a note on my blog : http://www.casualtek.com/index.php?/archives/94-You-like-DRM-Youll-enjoy-CPRM-!.html
I invite to share your experience there, for the french speaking people. I’ll do my best to translate the most interesting comments.