mjb@acd4.UUCP ( Mike Bryan ) (09/09/89)
In article <FOX.89Sep5161157@cs.cs.columbia.edu> fox@cs.cs.columbia.edu (David Fox) writes: >I'm pretty sure this is how the DAT copy protection *really* works: > > CDs are marked "I'm copyrighted" in their non-audible info. > > When a DAT records something marked "I'm copyrighted" it > produces a copy marked "I'm a copy of something copy- > righted." > > DATs will refuse to copy something marked "I'm a copy of > something copyrighted." First, a nit to pick: all above occurances of "copyrighted" should be "copy-protected". Commercial recordings are (always?) copyrighted, but none (few?) have been copy-protected, and won't be until the DAT issue is resolved. David's description matches my understanding of DAT copy protection, as gleaned from an article in a recent issue of Electronic Engineering Times. However, I have a really serious worry about this scheme: what's to prevent a CD manufacturer from marking the CD "I'm a copy of something copy-protected"? All they have to do is change the value of the appropriate sub-code, and the DAT will refuse to copy it. Then I couldn't even make my own private copy! Surely they wouldn't be so restrictive, would they? Just because they originally championed protection schemes which allowed absolutely no copying, we can trust them now, right? It really alarms me that I haven't seen any discussion of this possibility. Since the recording industry hasn't said they will not do this, I have to believe they are at least considering the idea. Greedy little buggers. On a more positive note, the copy protection scheme also allows CDs to be marked as "no copyprotect", so that you *could* make copies of your copies (of your copies...). Let's hope that some labels/artists are smart enough to do just this, making the whole issue of copy-protection totally moot. -- Mike Bryan, Applied Computing Devices, 100 N Campus Dr, Terre Haute IN 47802 Phone: 812/232-6051 FAX: 812/231-5280 Home: 812/232-0815 UUCP: uunet!acd4!mjb ARPA: acd4!mjb@uunet.uu.net "Did you make mankind after we made you?" --- XTC, "Dear God"
yh0a+@andrew.cmu.edu (Yary Richard Phillip Hluchan) (09/13/89)
I think it makes more sense for the DAT copy-protection to work like this: DAT can take 44.1 kHz data ==> 48 kHz DAT will not take 48 kHz data 44.1 kHz is the rate CD's are recorded at, 48 kHz is the DAT rate. Of course, this method would not let you make DAT-to-DAT tapes of your daughters first glockenspiel recital, but the record companies don't care about that! (Note also that the copy-protection will not prevent you from re-digitizing the analogue output) Question: Has anyone SEEN the specs, the DETAILS?
ketil@ifi.uio.no (Ketil Kirkerud) (09/13/89)
In article <sZ3O9Ae00WB_B0829S@andrew.cmu.edu> yh0a+@andrew.cmu.edu (Yary Richard Phillip Hluchan) writes:
I think it makes more sense for the DAT copy-protection to work like this:
DAT can take 44.1 kHz data ==> 48 kHz
^^^
This takes quite a bit of signal processing to do, and would raise the price
of DAT decks a LOT..
DAT will not take 48 kHz data
44.1 kHz is the rate CD's are recorded at, 48 kHz is the DAT rate.
Of course, this method would not let you make DAT-to-DAT tapes of your
daughters first glockenspiel recital, but the record companies don't care
about that!
This, of course, will be the largest problem : My main use for DAT
(when I get hold of one...) will be for music recording/mastering :
Not being able to make (digital) copies would seriously cripple
the usefulness of the system : There is always som editing, etc
to be done..
---Ketild88-jwa@nada.kth.se (Jon W{tte) (09/14/89)
In article <2013@ifi.uio.no> ketil@ifi.uio.no (Ketil Kirkerud) writes: >In article <sZ3O9Ae00WB_B0829S@andrew.cmu.edu> yh0a+@andrew.cmu.edu (Yary Richard Phillip Hluchan) writes: >This, of course, will be the largest problem : My main use for DAT >(when I get hold of one...) will be for music recording/mastering : >Not being able to make (digital) copies would seriously cripple >the usefulness of the system : There is always som editing, etc >to be done.. I don't think this will be a problem. From what I've heard, DAT can playback at 32kHz, 44.1kHz and 48kHz, but record at only 32kHz and 48kHz, thus making it impossible to copy directly. Unfortunately, this was easily patched in DAT decks, so the manufacturers considered using a blocking tone (yes, adding a high-pitched note and then trying to filter it in the D/A stage -- fools !) to protect CDs. I'm happy that they seem to have left this approach... The only problem with dubbing should be in 44.1kHz, 48kHz would be no problem, since you can't get there directly from CDs. -- Another good night not to sleep in a eucalyptus tree.
curt@dtix.dt.navy.mil (Curt Welch) (09/14/89)
In article <1745@convex.UUCP> forsythe@convex.com (Charles Forsythe) writes: >yh0a+@andrew.cmu.edu (Yary Richard Phillip Hluchan) writes: >>44.1 kHz is the rate CD's are recorded at, 48 kHz is the DAT rate. > >Actually, there was an old Sony DAT which is being OEM'ed by some pro-audio >company as a CD-mastering unit that has a switch for 44.1 or 48 -- could >DAT machines be modified with reasonable effort? I doubt there's anything >in the storage format that relies on 48KHz. The R-DAT standard defines 3 sampling rates for DATs: 32 kHz, 44.1 kHz, and 48 kHz. The recording rate is encoded on the tape so when it is played back, the DAT deck automatically selects the proper playback rate. DAT decks, like VCRs, can record and play at different rates. Which rates are supported by a specific model is a decision that the manufacturer makes when they design and market the product. If the deck isn't designed to record at 41.1 kHz, then I doubt that it would be feasible for any home hacker to modify it to do so. What does happen, is that a company will design a product that can record at 44.1 kHz and 48 kHz, but then decide to sell a crippled version that only records at 48 kHz. My Panasonic SV-3500 is like this (I assume because of the RIAA debate). It can play tapes at all 3 rates. It can record from the analog inputs at 44.1 kHz and 48 kHz. But, according to the manual, it can only record at 32 kHz and 48 kHz (not 44.1) from the digital input. However, if you remove the cover from the version I have, you find an undocumented slide switch. This switch, I was told, allows you to record at 44.1 kHz from the digital input. I don't own a CD player with digital outputs yet, so I haven't been able to test this. I have, however, changed the position of the switch. Curt Welch curt@dtix.dt.navy.mil
brian@apt.UUCP (Brian Litzinger) (09/14/89)
In article <2013@ifi.uio.no>, ketil@ifi.uio.no (Ketil Kirkerud) writes: > > DAT will not take 48 kHz data > > 44.1 kHz is the rate CD's are recorded at, 48 kHz is the DAT rate. > Of course, this method would not let you make DAT-to-DAT tapes of your > daughters first glockenspiel recital, but the record companies don't care > about that! > > This, of course, will be the largest problem : My main use for DAT > (when I get hold of one...) will be for music recording/mastering : > Not being able to make (digital) copies would seriously cripple > the usefulness of the system : There is always som editing, etc > to be done.. I've been told there are industrial DAT recorder/players that you can purchase that operate at 44.1 Khz. This makes perfect sense giving that a studio would want to master directly to DAT tape at the correct rate for later mastering to CD. The main problem with industrial units is the cost. The second problem with industrial units is that the tapes you make in your industrial unit won't play too well in your 48 Khz car DAT player. <> Brian Litzinger @ APT Technology Inc., San Jose, CA <> UUCP: {apple,sun,pyramid}!daver!apt!brian brian@apt.UUCP <> VOICE: 408 370 9077 FAX: 408 370 9291
rob@raksha.eng.ohio-state.edu (Rob Carriere) (09/15/89)
In article <sZ3O9Ae00WB_B0829S@andrew.cmu.edu> yh0a+@andrew.cmu.edu (Yary Richard Phillip Hluchan) writes: >I think it makes more sense for the DAT copy-protection to work like this: > >DAT can take 44.1 kHz data ==> 48 kHz >DAT will not take 48 kHz data > >44.1 kHz is the rate CD's are recorded at, 48 kHz is the DAT rate. >Of course, this method would not let you make DAT-to-DAT tapes of your >daughters first glockenspiel recital, but the record companies don't care >about that! > >(Note also that the copy-protection will not prevent you from re-digitizing the >analogue output) > >Question: Has anyone SEEN the specs, the DETAILS? From the latest IEEE Institute: 1) DATs will contain elctronics to allow them to record at the proper sampling rate to digital CD->DAT. Digital DAT->DAT is obviously no problem. 2) The recorder will read the header info from any source being copied digitally. This header will specify (among other things) whether the source is 1) CD, 2) copyrighted DAT, 3) non-copyrighted DAT. It will allow limited copies in cases 1 and 2 (a different number, I think it was 2 and 3, but I don't have newsletter here) and unlimited copies in case 3). Analog to digital copies will be flagged as 2), to prevent you from making unlimited copies of copyrighted analog material. SR
kjones@talos.uucp (Kyle Jones) (09/15/89)
Rob Carriere writes: > From the latest IEEE Institute: > [...] > 2) The recorder will read the header info from any source being copied > digitally. This header will specify (among other things) whether the source > is 1) CD, 2) copyrighted DAT, 3) non-copyrighted DAT. It will allow limited > copies in cases 1 and 2 (a different number, I think it was 2 and 3, but I > don't have newsletter here) and unlimited copies in case 3). Analog to > digital copies will be flagged as 2), to prevent you from making unlimited > copies of copyrighted analog material. This raises some questions: 1) Presumably the DAT recorder will keep an internal table of (CD-ID, copy-count) pairs. (Just marking copies won't work: a copy of a copy could be stopped, but you could still make unlimited copies of the original CD.) How much memory in the DAT recorder will be devoted to this table? 2) How much will this affect the price of a DAT recorder? 3) What do you do when there's no more room in the table for new (CD-ID, copy-count) pairs? (Buy more memory for your DAT recorder? :-| ) Also, flagging A/D copies as copyrighted DAT prevents me from making unlimited digital copies of my own digital masters, just because my mixer has analog outputs. I have to buy a mixer with digital outputs, or put an A/D converter between the mixer and the DAT recorder so my master will be flagged as non-copyrighted DAT. Pardon me while I throw back my head and scream. kyle jones <kyle@cs.odu.edu> ...!uunet!talos!kjones Up ahead someone uttered a gobbling scream, and then the rifles crashed in unison.
bob@tinman.cis.ohio-state.edu (Bob Sutterfield) (09/15/89)
The discussion, though fascinating, has varied far afield from its origin as an example of the heinous practices of software distributors. Could we please move the technical discussion (of how to set up a home digital recording and patching studio) over to solely rec.audio and out of gnu.misc.discuss? Thank you!
kline@arizona.edu (Nick Kline) (09/16/89)
In article <1989Sep15.134921.14736@talos.uucp> kjones%talos.uucp@uunet.uu.net writes: >This raises some questions: > >1) Presumably the DAT recorder will keep an internal table of (CD-ID, > copy-count) pairs. (Just marking copies won't work: a copy of a > copy could be stopped, but you could still make unlimited copies of the > original CD.) How much memory in the DAT recorder will be devoted to > this table? No, you can still make as many copies of an *original* as you want. It does not limit this. Now really, how could you keep track of what cds you had already copied? There is the possibility of being billions of different cds available and there is no organization that assigns id numbers (that I know of, and I do know that you can go to independant orgs and get a cd pressed). The limit is on the number of copies of copies you can make. -Nick --- "Computer Scientists are at the top of the nerd heap" - Curtis Dyreson Nick Kline, Univ. of Az., Computer Science, Tucson, AZ 85721 (kline@arizona.edu -or- {noao|allegra|cmcl2}!arizona!kline)
yh0a+@andrew.cmu.edu (Yary Richard Phillip Hluchan) (09/16/89)
>digitally. This header will specify (among other things) whether the source >is 1) CD, 2) copyrighted DAT, 3) non-copyrighted DAT. It will allow limited >copies in cases 1 and 2 (a different number, I think it was 2 and 3, but I >don't have newsletter here) and unlimited copies in case 3).__Analog to >digital copies will be flagged as 2), to prevent you from making unlimited >copies of copyrighted analog material...... This means you need a pro machine to make a non-copy protected orginal. This also means my home DAT player will think I want to copyright my daughter's glockenshpiel recital, and won't let grandma make a copy of her tape to send to Cousin Zeke in Duluth. I'm glad I'm a computer engineer!
yh0a+@andrew.cmu.edu (Yary Richard Phillip Hluchan) (09/17/89)
Actually, this whole copy protection scheme will hardly put a dent in illegal copyright violations. Think about you friend's bootleg tapes. Think abuot your own (if you have any! :-) How many of those are third-generation? If I'm not mistaken, the usual bootleg come-on lines are: 1) Ooh! You have that on CD? Man, can I get a tape? 2) Gee, is this album any good? and sometimes 3) This has been out of print for _ yrs, think I could tape it? Almost no-one copies copies of tapes. No one I know, at least.
curt@dtix.dt.navy.mil (Welch) (09/17/89)
In an article yh0a+@andrew.cmu.edu (Yary Richard Phillip Hluchan) writes: >This means you need a pro machine to make a non-copy protected original. This also means you can make a copy-protected original without a pro machine! If your recording is good enough that everyone wants a copy of it, then you probably want it copy-protected. >This >also means my home DAT player will think I want to copyright my daughter's >glockenshpiel recital, and won't let grandma make a copy of her tape to send >to Cousin Zeke in Duluth. I'm glad I'm a computer engineer! It only means that grandma can't make a DIGITAL to DIGITAL copy! She can make a copy from the ANALOG input, and then make as many digital copies of that master as she wants. Have you ever heard a DAT copy of a CD through the analog inputs? It's _much_ better than anything you can do with cassette. I've done simple A/B tests between a CD and a DAT recorded from the CD and I can't hear a difference. If cousin Zeke needed that good of a copy, why didn't you send your grandma two copies in the first place? I know that no one likes to have their rights restricted, but I feel the proposed copy-protection scheme is _very_ fair. I didn't like the CBS system and Solocopy is just stupid. Two years ago, when DAT first came out, the manufactures decided to build models that could not recorded at the CD rate of 44.1 kHz, and when recording from the digital input, it would not record if the input was marked copy-protected. The RIAA bitched and said this was not good enough. Now, because of their bitching, we have SCMS. With SCMS, we can still do all the unlimited, unrestricted, analog copying that we have been dong with cassettes; we can make an unlimited number of digital copies of copy-protected material; we can make our own copy-protected recordings without buying pro equipment; and the recording industry has better protection of their markets than they did two years ago. I think we should thank the RIAA for what they did. Curt Welch curt@dtix.dt.navy.mil
kjones@talos.uucp (Kyle Jones) (09/19/89)
Yary Richard Phillip Hluchan writes: > This means you need a pro machine to make a non-copy protected original. Curt Welch writes: > This also means you can make a copy-protected original without a pro > machine! If your recording is good enough that everyone wants a copy > of it, then you probably want it copy-protected. Ah, I knew this topic would drift back into realm of GNU eventually. Suppose I don't want to sell my music or protect it in any way other than keeping other people from restricting its distribution. Sound familiar to you GNUs? And my reasons for this need not be altruistic. For example, giving away tapes is a good way to expose people to your music. All other things being equal, the better the quality of the recording, the more favorable the impression you'll make. If you get enough of a following, then you might be able to SELL some music someday or, if you're really lucky, be offered record contract. At the very least you might land some gigs. Thanks to this gratuitous copy protection, people won't be able to freely share music that I WANT them to give away. People shouldn't be forced to take a trip down Analog Lane just to be able to make more copies for their friends. If this topic still does not seem germane to the newsgroup gnu.misc.discuss, imagine if computers marked disks and tapes, and refused to make third generation copies of ANY data, copyrighted or not. kyle jones <kjones@talos.uu.net> ...!uunet!talos!kjones p.s. All of this presumes DAT will eventually become affordable enough to dip into the cassette tape market. If it doesn't then the point is moot, because no one's going to sink a fortune into a DAT player just to listen to flawless bootleg copies of CDs, when CD players for your home, car, and shoulder are already available and affordable.)