Skip to main content ↑ ↓

Notice

Please note that most of the software linked on this forum is likely to be safe to use. If you are unsure, feel free to ask in the relevant topics, or send a private message to an administrator or moderator. To help curb the problems of false positives, or in the event that you do find actual malware, you can contribute through the article linked here.
Topic: New feature for burning software--way to burn uncertain bits (Read 5497 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

New feature for burning software--way to burn uncertain bits

Sometimes you can't rip a CD 100% right--some places are beyond recovery. EAC (or whatever you use) gives you a guess of what was there, which more likely than not is wide off the mark. So you use this file to burn a CDR. When you play it, there's one way in which the CDR is inferior to the CD: whereas the damaged part of the original CD is read all in a jumble by the CD player and it applies error coverage, the corresponding part of the CDR will contain clean, WRONG info that is read by the player and played back exactly as is. *wince*

Is there some way to tell the CD burner to burn the CDR so that this doesn't happen? E.g. you can write bad C1 and C2 information in these parts deliberately. I'm guessing that such a way to burn a CDR currently doesn't exist--since CDRs are burned from standard wav files--and that the only way to get such a feature would be to write a new integrated rip + burn program that stores ripped data in a special format...

But I'd love to be surprised

New feature for burning software--way to burn uncertain bits

Reply #1 –
I think it needs some firmware changes in recorder, since mmc command doesn't support that kind of recording. Even CloneCD cannot write C1 or C2 error.

New feature for burning software--way to burn uncertain bits

Reply #2 –
mp3chan is right, it is not possible to burn any error on purpose on an audio CD with a regular burner (but CD factories can do it, Safe Audio protection relies on it).

At CDFreaks, we discussed how it was possible to burn unreadable sectors (SD2 weak sectors) with burners (http://forum.cdfreaks.com/showthread.php?s=&threadid=47745 ) choosing the data carefully so that there is too much pits or too much lands (DS too low or too high), and the tracking system is disturbed. But this only works for entire sectors, I think.
Anyway, it's not possible to turn one given sample wrong.

New feature for burning software--way to burn uncertain bits

Reply #3 –
Then, is it also impossible to extract audio data bit by bit? That is, the CD drive would report C1 and C2 errors, but it won't send all the data including the C1 and C2? Or does CloneCD do that?

New feature for burning software--way to burn uncertain bits

Reply #4 –
CloneCD don't do that, nor any other program. It's the hardware inside the drive that is in charge.

The C1 and C2 errors occur at a lower level of encoding than the "raw" mode.

More details :
http://www.ee.washington.edu/conselec/CE/k...audio2/95x7.htm

New feature for burning software--way to burn uncertain bits

Reply #5 –
hmm... in this case how can EAC work with a drive that doesn't report C2 errors?

New feature for burning software--way to burn uncertain bits

Reply #6 –
I'm not sure I understand the question. In your shoes, I would have asked the opposite : "since C2 is hidden, how can EAC use it ?"

Answer 1 :
Some drives can return C2 flags while extracting audio.
The C2 data is still hidden, the C2 error recovery process is still hidden, but the result of the process -Good or bad- (one bit) is returned to the OS. That's what EAC and Feurio can read.

Original question : how does EAC work without C2
Anwser 2 :
As explained in the http://www.exactaudiocopy.de website, as well as the Readme and FAQ.txt that comes with eac, in the Program files/EAC/Docs folder, EAC assumes that if a CD is unreadable, the info returned will be random. So reading twice everything, if differences show up, it means an error ocurred.
It has proven to be effective to detect errors.

New feature for burning software--way to burn uncertain bits

Reply #7 –
So if my drive doesn't report C2 errors, EAC has to read everything twice--I assume this slows everything at least by half! Phew, thank god my drive does report

New feature for burning software--way to burn uncertain bits

Reply #8 –
Joe Bloggs:

But does your drive report C2 correctly, and accurately ?

From what I've found, only the Plextor drives report C2 correctly all the time, even on scratched discs.

Every other drive seems to have problems with C2 reporting, even the ones that allegedly 'support it'.

Best way to test is find some cds that are fairly scratched (but not too scratched as to be unreadable). 

With C2 on, use the test & copy function in EAC.  Copy the CRC values from the log function (they should match).

Now turn off C2, and try test & copy again.  You should get the same CRC values as from the first test all over again. 

I'm not a fan of the C2 feature in EAC, as many people seem to falsely assume that it's working with their drive, just because:

A) the extraction works with it on, so 'It must be working with my drive!'

or

B) they see on a website, or on a list of features somewhere, that their drive supports C2.  Unfortunately, from the testing I've seen, it's rarely used accurately by the drive.

The Plextors seem to use C2 perfectly all the time.

A relevant link:

http://www.digital-inn.de/showthread.php?s=&threadid=14640

chris

New feature for burning software--way to burn uncertain bits

Reply #9 –
Is there someone with a good Plextor willing to test its C2 accuracy with one of my awful CDRs ?

New feature for burning software--way to burn uncertain bits

Reply #10 –
Hm, I ran the 'test' at the beginning and EAC says my Panasonic CDRW drive supports C2 error reports

And that's all I know

And I have encountered <100% quality and long re-reads even with C2 enabled, unlike the case with the guy in the link you posted.

New feature for burning software--way to burn uncertain bits

Reply #11 –
Do you usually turn the "use c2 error information for error correction" option on or not? Which one is better?

New feature for burning software--way to burn uncertain bits

Reply #12 –
Hm, I ran the 'test' at the beginning and EAC says my Panasonic CDRW drive supports C2 error reports

And that's all I know

Yes, unfortunately that's all most people know, because EAC doesn't really warn you about the fact that very few drives REALLY support C2 accurately.

Here's a link to a relevant discussion on the EAC message board:

http://www.digital-inn.de/showthread.php?s=&threadid=14600

chris

New feature for burning software--way to burn uncertain bits

Reply #13 –
*groan*

New feature for burning software--way to burn uncertain bits

Reply #14 –
Quote
Originally posted by mp3chan
Do you usually turn the "use c2 error information for error correction" option on or not? Which one is better?


this is weird, when i use c2 with my plextor 24x burner i can get a single 100% quality track, but when i leave only accurate stream read or stuff, i get 100% quality tracks all the time!!! ??? it only depends on tweaking the speed.

New feature for burning software--way to burn uncertain bits

Reply #15 –
Quote
Originally posted by Phobos
this is weird, when i use c2 with my plextor 24x burner i can get a single 100% quality track, but when i leave only accurate stream read or stuff, i get 100% quality tracks all the time!!! ??? it only depends on tweaking the speed.


Did you check cache ? If you forgot while your drive needs it, it's not surprising. It is supposed to behave like that.

New feature for burning software--way to burn uncertain bits

Reply #16 –
no, cache wasnt checked, ill try it too, but i think i did once and still get better results without it...