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Excessive Copy Protection?, Mp3 related
Dub45
post Jan 3 2003, 05:31
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This may be old news to some of you but its the first time that I have come across it.

I have just bought a copy of 'Round about Roma' by Stefano Di Battista on Blue Note.
This disc does not seem to have been released in the US yet.

I put it into my pc to have a listen while I browsed and suddenly a player that I had never seen before appeared! Anyways the cd provides its own player but apparently will not allow me to use my usual player to rip it as I usually do for use on my ipod.

When I opened the cd through explorer it does not display the audio tracks separately.

This is infuriating (I dont share MP3s on the net and I don't download them) but I can't listen to an album that I have bought as I would wish!

I presume the introduction of the player is to get over the complaints of cds not being playable on pcs.

Any other incidents of such cds? What are other people's views?

Incidentally I tried to copy it on a 'normal hi-fi type copier and it wont copy either!
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neomoe
post Mar 18 2004, 06:23
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From: Europe/Germ./MA
Member No.: 7255



Tigre,

do you know a non-commercial program with what I can do something equal to what you did with cool edit?
and I do not really understand, what You exactly did.. huh.gif I mean this:

QUOTE
ripped files
p plextor secure noC2 7,9speed test/copy CRC OK "gold standard"
q 2nd drive
r 3rd drive ...
n new file, containing of best possible samples of p,q,r

algorithm
if p=q then n=p [# I]
else if p=r then n=p [# II]
else if q=r then n=q [# III]
else n=p [# IV; no values match, so trust "gold standard"]

simplified:
if q=r then n=q
else n=p

To "program" this in Cool edit I had to do following steps (note: dithering must be disabled):

1. Difference

a=q-r b=p-q

problem: "clipping": a and b can have every value between -65534 and 65534, while in 16 bit audio there are only values between -32767 and 32767 possible. Solution: amplify to 50% before substracting, add twice if needed, correction of introduced errors see 4.

a=q-r is done in CEP by a="mixpaste_overlap(invertŪ;q)" (for a clipping is not an issue, because it'll be "booleanized", see 2.)
b=0,5*p-0,5*q : b="mixpaste_overlap(invert(amplify(q;50%));amplify(q;50%))"

2. Goal: 0 sample stay 0 sample, convert everything else to 32767 (boolean 1)
function: "booleanize"

a_b=booleanize(a) : a_b="mixpaste_modulate(amplify(a;+91dB);amplify(a;+91dB))"

Mixpaste_modulate problem: CEP mixpaste_modulate (edit>mixpaste check modulate in dialog) is should multiplicate 2 values and divide by 32767. Checking the results I found out that it lowers the value by 1. So "Booleanize" produces 0 on zero samples, on all other samples sometimes 32766, instead of 32767.
To avoid this and get only 0 or 32767 samples I used a_b_new="amplify(a_b;+1dB)"

3. Goal: if for a sample a_b_new=32767, then sample value shall be n=p=2*b+q ; if a_b_new=0, sample value n=q
n=& quot;mixpaste_overlap(mixpaste_overlap(q;mixpaste_modulate(a_b_new;b));mixpaste_modulate(a_b_new;b))
"

Here the "mixpaste_modulate problem" occured again. It produced differences of the value 1 (eg. 23765 instead of 23766).

4. Correction of "clipping" and "mixpaste_modulate" inaccuracies:

c=p-n : c="mixpaste_overlap(invert(n);p)" (clipping no issue, because further needed samples have small values)

c needs correction to make the following mixpaste_overlap operation exact. 0 samples have to stay 0, negative have to be decreased by 1, positive increased by 1 (see "mixpaste_modulation problem")

c_corrected="mixpaste_overlap(c;amplify(amplify(c;+91db);-90,3db))"

n_corrected="mixpaste_overlap(mixpaste_modulate(a_b_new;c_corrected);n)"


could you give me an description for idiots?


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Posts in this topic
- Dub45   Excessive Copy Protection?   Jan 3 2003, 05:31
- - Sachankara   Return the disc and demand your money back... Arti...   Jan 3 2003, 05:33
- - woody_woodward   I agree. The disk is defective. Take it back. T...   Jan 3 2003, 06:59
- - CiTay   QUOTE (Dub45 @ Jan 3 2003 - 05:31 AM)I presum...   Jan 3 2003, 14:44
- - theduke   QUOTE (CiTay @ Jan 3 2003 - 02:44 PM)The play...   Jan 3 2003, 14:48
- - ronnie_t   see this topic on cdfreaks. It tells you how to re...   Jan 3 2003, 23:10
- - Gecko   I've also had one of those (Dj Convention - Co...   Jan 4 2003, 00:05
- - kennedyb4   QUOTE (woody_woodward @ Jan 3 2003 - 12:59 AM...   Jan 4 2003, 00:55
- - tigre   I got a similar cd as christmas present. It launch...   Jan 4 2003, 03:41
- - Pio2001   QUOTE (tigre @ Jan 4 2003 - 05:41 AM)there ar...   Jan 4 2003, 04:45
- - tigre   @Pio2001: Before I forget about it: You're a ...   Jan 4 2003, 13:28
- - layer3maniac   QUOTE (tigre @ Jan 4 2003 - 04:28 AM)could yo...   Jan 4 2003, 13:57
- - SK1   Maybe it's got something to do with a hacked f...   Jan 4 2003, 14:47
- - tigre   OK I trust layer3maniacs statement. What I did is ...   Jan 4 2003, 16:58
- - Pio2001   QUOTE (tigre @ Jan 4 2003 - 03:28 PM)The firs...   Jan 4 2003, 22:47
- - outscape   >>>'Anyways the cd provides its own ...   Jan 5 2003, 07:58
- - ronnie_t   I succesfully made a backup of my cactus-protectec...   Jan 5 2003, 13:10
- - deej_1977   Hi all, In this thread I complained about copy pr...   Jan 5 2003, 14:29
- - tigre   @Pio2001: Thanks a lot for your detailed informat...   Jan 8 2003, 19:42
- - neomoe   Tigre, do you know a non-commercial program with ...   Mar 18 2004, 06:23
- - tigre   I don't know any software capable of doing thi...   Mar 18 2004, 07:46
- - shadowking   Sounds like Cactus data shield CDS200 protection. ...   Mar 18 2004, 08:56
- - Lev   QUOTE (Gecko @ Jan 4 2003, 12:05 AM)What both...   Mar 18 2004, 09:58
- - jido   QUOTE (tigre @ Jan 3 2003, 06:41 PM)I got a s...   Mar 18 2004, 10:59
- - tigre   Just in case noone noticed so far: This thread is...   Mar 18 2004, 13:54


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