PI/PIF... does anyone know?

If PI errors are “good” errors… meaning they will not make dvd disks unreadable then what does it matter how many of them you have? I mean you can average 30 or 130 of them but if disc is readable anyway why would I care.

Is it that increasing amount of PIs will at some point slide into PIF zone?

Or is it that over time dvd surface, checmical, will likely to deteriorate with higher PI so after some time you’re likely to end up with unreadable disc?

Is it that algorithm that fixes PI is guaranteed to succeed as opposed to PIFs which are by standard fixable if there are maximum “8 in a row” (or something like that)? Although I am sure lots of dvd drives will be able to fix even worse results.

Can someone… C0de nudge nudge wink wink … shed some light on this please?

Greatly appreaciated.

[PIs and PIFs remind me a bit of error detection and correction for linear information encoding… some stuff I learned about at one of the unversity courses]

PIF = Parity Inner Failures. Errors left after PI correction, so the PI correction was not able to correct all of the errors.

Also have a read of these:
http://www.cdfreaks.com/article/147/5
http://kprobe.cdfreaks.com/

that was a good read… “write quality” chapter it does explain what i am asking about. thanks C0de.

now that I know magical numbers being 280 and 4 I suggest kprobe author to add them to the program, really it would make it a bit clearer as to what burn you can be ok with, what is covered by standard so you can expect the disc would be readable in virtuallly all readers.

something like this:


280/4 is for 1x scanning only. You can also sometimes have playback issues with lower numbers, due to the density of the errors. It really depends on the player, some can handle much higher rates than 280. So in fact, there are no magical numbers, it’s all relative.

I understand that, I just had to use the word “magical” because those were the first guideline numbers I had. And that’s what they are (as the author of the article said… most of the drives would behave correctly). All I had before was the comparison with other results and knowing “the lower the better”. This is good.

On top of that… if you scan PI < 280 at 4x , then your chances to scan PI < 280 at 1x would usually be much bigger. Cool!

Ok, the whole thing is that ProdiscF01 burn quality is quite ok when it comes to PIFs read in 832S… but I was wondering about those high PIs (check the previous graph). What does that mean… should I just throw away those burns and the whole pile of discs or not? Now I know I don’t have to. And that’s GOOD. I’d really be maad :a

I am gonna scan it at 1x … now I’m curious :slight_smile:

There are 2 primary concerns when you see high PI levels. First is compatability in players. Some players might have trouble with the disc. So it increases the odds of compatability troubles.
Second is longevity. Experience with CDR’s taught us that high error rates mean increased chances of degradation over time with increasing error rates.

Looking at your posted scan, I would look for a way to get lower errors on that media. Either by changing burn speed or by changing firmmware versions, or both. I don’t think I would throw the media away, Prodisc is generally pretty good stuff, in the right burner.

Longevity was/is my concern. I was able to read the disc after the burn (in 832S) and since it’s all data files I am not worried about standalone dvd players or other dvd readers compatibility. I like to think that most of dvd readers out there would be able to read it, as technology goes forward, right, better equipment/algorithms are being developed.

I ran Nero’s quality scan, and it was smooth almost perfectly. Now if Prodisc is good stuff (physical properties of the dvd surface in regards to its degradation over time) then I shouldn’t worry about it. I will however check it out after couple of months to either confirm this theory or go berserk… :wink:

The scan I posted is VS0B firmware with TYG02 strategy instead of the original. Original sucked donkey balls. Check ot out:

http://club.cdfreaks.com/showthread.php?t=109048

Oh yeah, one more thing, I tried burning the same media on friend’s NEC 3500A and needless to say it was much better. PI graph was entirely below 100. Number of PIFs was halved at least.

Yes, scan every couple months for the 1st year, or keep 2 copies.

Or, just buy a NEC and forget about scanning. :iagree: