How many C2/PIF will likely lead to unreadable errors on a CD/DVD?

How many C2/PIF will likely lead to unreadable errors on a CD/DVD ? :slight_smile:

After testing a lot of discs, I’m pretty sure there’s no good answer to that question.

If you have a CD with zero C2 errors it should be readable in that drive.

If you have a DVD with PIF per 1 ECC block being 4 or less over the whole disc, that disc should be readable in that drive.

Other than that the variations can be quite staggering.

You can have some spikes here and there that are pretty high, like 10 or more and it won’t usually cause an error unless there are a whole load of them in the same area.

As drage said though, it depends on the drive the media is being read with.

I’ve had unreadable discs with excellent scans and I’ve had discs with excellent TRTs with awful scans.
The C2 and PIF are not on the disc. They are only the read errors encountered by the drive, so drives can be very different at that.

Tested on the same drives?


Readability & PIE/PIF scans have very poor correlation on modern drives. If your just concerned about readability, forget digital error scanning, it is much less useful for that purpose than TRT (preferably at 16x on non-over tolerant drives).

Isn’t it that PO failures appear when so many high PIFs accumulate that drive can no longer correct them ?

In theory, yes. The drive will slow down then.

So there is correlation between PIF and read errors.

TL0: I find it hard to believe there’s no correlation. After all, these scans are (more or less) the number of errors the drive deals with as it reads the data.

For me there always was very good correlation (with NEC ND3520, Sony CRX230ED, Yamaha CRW8824, Creative iNFRA4800).

As I said, [B]‘poor correlation’[/B], not no correlation.

If I see PIE/PIF reach upper limits on what the drive reports, then yes, readability can become an issue, but it doesn’t neccessarily mean the data is unretrievable, it can be very dependant on drive used.

With lower PIE/PIF reported, correlation becomes less. The only time I normally see very good correlation is when a drive becomes frozen during digital error scanning, then readability will also be very problematic in my experience.

If the drive used for error scanning is reliable, a disc will be readable by that drive at least at the scanning speed when E32 = 0, or PIF max < 10 at Sum 1, or POF = O. If the drive is not reliable, a disc may be unreadable even when C1/C2/PI/PO errors are within specs.

If there is very poor correlation between readability and PI/PO error scans, the error rates reported by that drive is not reliable.