Newsgroup: it.comp.hardware.cd
Titolo: Articolo del creatore di CLONE CD

As you know, there is a new copy protection, which can not always be copied
with CloneCD. For example, you can find it on the CD "Command & Conquer -
Red Alert2" and on some others as well. Let's call this protection SD2.
SD2 is a very interesting beast, as some of you already know. Sometimes a
copy works only in the CD-Writer, sometimes not at all. Sometimes -
depending on the writer used - in any CD-ROM.
Some people claim, that they had success with other burning software.
Let me explain, what the reason for all this might be. (I say "might be", as
the information here is just revealed through observation, but I believe I
am at least pretty close)
The first funny thing is, that if a SD2 copy doesn't play in a CD-ROM, this
copy has additional bad sectors, which weren't on the original. As CloneCD
reads and writes "as is!", I would have assumed, this is simply impossible.
So, if you are a curious guy, you can look at these sectors on the original
CD (where they are readable).
You will find a lot of garbage on the first view. But if you run these
sectors through a sector scrambler (a device, which is in every CD-ROM and
CD-WRITER) you see the reason for all the trouble: Regular patterns like
'XYXYXYXYXY...' and so forth.
And this is exactly how the protection works. To understand this, you need
to know, what the scrambler is used for (from ECMA-130, ISO/IEC 10149):
"A regular bit pattern fed into the EFM encoder can cause large values of
the digital sum value in case the merging bits cannot reduce this value. The
scrambler reduces this risk by converting the bits in byte 12 to 2351 of a
Sector in a prediscribed way. ..."
The sectors I have mentioned above try in fact to overload the EFM encoder
of the CD-Writer, because *AFTER* passing the scrambler the poor device has
to write *REGULAR BIT PATTERNS* - something it really doesn't like.
After some quick tests, it seems, that some writers are affected by this
problem more than others.
For example, writers based on Philips hardware (Philips, Fujitsu/Siemens,
Acer, just to name a few) are NOT affected by this at all. With such a
writer, you can copy SD2 with any CloneCD version, and the copy will run on
every CD-ROM.
Most other writers will not write these sectors correctly. Some writers
(Plextor) can at least read the copy they've made, so the copy will run in
the writer, but not in an ordinary CD-ROM.
The reason for this might be, that the writer is able to position better,
but this is just guess.
I must admit, this is a very, very cool protection: Something is on the
original which can be read, and not be written. I really didn't believe such
a protection is possible.
Now for the interesting question: Will CloneCD ever be able to overcome this
problem?
Well, you can answer this yourself: I guess not. Okay, you can probably do
nasty tricks like modifying the pattern. But this isn't what CloneCD is
about. It is called CloneCD, not PatchCD. In opposite to the belief of some
people, CloneCD does not cheat or modify data in any way. I like to keep it
this way.
Will any other software overcome this problem? Again, you can answer this
yourself: No, unless they are cheating somehow.
Can a firmware update fix this? Maybe. But I have the strange feeling, that
the problem resides in the writer's chipset, not its firmware. Maybe a
firmware workaround would be possible. But who would be so nice to modify
the firmware in this regard?
Conclusion: Either use your Plextor writer to play the copy, or buy a unit
based on Philips hardware.
Sorry for the bad news.
Oliver Kastl - Creator of CloneCD

 ha scritto nel messaggio
news:95jl2c$2vr$1...@nread2.inwind.it...


Io ripeto che ho un plextor40 in lettura, scrivo con il teac55s e le copie
me le legge qualunque lettore.
Pero' non uso clone. Leggo con blindread e scrivo con cdrwin o diskjuggler.
In compenso per me copiare SECUREROM è impossibile (senza crk).
Ciao
Faxbio