Question about USIng Nero CD SPEED

[KCK]

My round of applause goes for Inertia.

Inertia's posts are perfect examples of how to provide help in carefully worded answers, with the exposition level being suited to the needs of a given user, and without making any personal attacts. Unfortunately, it's impossible to stay impersonal when attacted by self-proclaimed "experts". The psychological profiles of such "experts" are well known, but apparently there are no clean and polite ways of dealing with them.

In this case, even after a couple of spath's replies, I see little need for continuing this discussion. Sorry for saying this, spath, but technical discussions require not only knowledge but also some intellectual discipline and culture, and you could learn a lot from Inertia. Even lack of proper education is no excuse for being impolite.

If you wanted to gain respect on this forum, you would have to observe basic rules first.

[Ian]

This thread reminds of of that saying..

Arguing on the Internet is like the Special Olympics. Even if you win, you're still retarded.

The only thing I'm taking from this whole thread is that CD Speed's documentation does not say what its showing in its tests and no one really knows for sure. If someone wants to drop Erik Deppe an email and try to get the answer from him, that would probably help end this "discussion".

[cfitz]

The only thing I'm taking from this whole thread is that CD Speed's documentation does not say what its showing in its tests and no one really knows for sure.

I'll second that. That is what I said when I left this thread a week ago before going on holiday. What a surprise to come back and see the unfortunate turn this thread has taken.

If someone wants to drop Erik Deppe an email and try to get the answer from him, that would probably help end this "discussion".

Sounds good, but it won't be me. I'm just a total stranger to him.

cfitz

[cdrfreak]

...Audio CD. Unlike data CD's, the yellow areas are uncorrectable...

I think this says it all. This can only mean that uncorrectable C2 errors are measured.

Reporting correctable C2 errors does not have much practical use.
Reporting uncorrectable C2 errors is very useful to check audio streams.

[cfitz]

...Audio CD. Unlike data CD's, the yellow areas are uncorrectable...

I think this says it all. This can only mean that uncorrectable C2 errors are measured.

If only it was so straightforward...

This just brings us back to what exactly is meant by "measured" and what is meant by "C2", which I think (at least as far as my reading of the interchange goes) was the crux of the initial disagreement between Inertia and Hitokiri and later spath. And even here, despite the enmity, I don't think there was disagreement on at least some of the basic principles. Everyone seems to agree that areas of the disc containing sufficient errors as to be uncorrectable at the C2 level are detectable and reportable to some degree. I think Inertia and spath even agree that within those areas, the exact number of bytes in error (or stated another way, the error type as in E32 vs. E42*, etc) can not be determined. Which still doesn't tell us what exactly CD Speed (or CD Doctor, for that matter**) is calling a C2 error and what the units are: is it E12 errors? E22 errors? E32 errors? E12 + E22 errors? E12 + E22 + E32 errors? Measured in absolute numbers of bytes with errors? Measured in bytes with errors per second? Measured in absolute numbers of blocks with errors? And so forth and so on...

One thing to toss in here is that EDC/ECC codes are generally able to detect more errors than they can correct. However, that doesn't mean that the EDC can properly classify how many errors occurred. Nor does it mean that the EDC can detect all errors. For example, a simple even/odd parity bit EDC scheme will detect one-bit errors, but can't correct any of those one-bit errors. It can also detect three-bit, five-bit, seven-bit, etc. errors, but can not distinguish any of these errors from any other, including one-bit errors. Moreover, it can't even detect two-bit, four-bit, six-bit etc. errors. The EDC/ECC used in CDs is more sophisticated than a simple parity bit, but the salient point remains the same: characterizing the behavior of these is not as straightforward as we would like.

So is this all useless? Nope. I will reiterate what I said earlier in this thread:

However, this doesn't invalidate the quest to characterize media and media/drive combinations. Certainly relative assessments of media quality are fair game. We may find that media X does consistently better than media Y when tested under identical conditions on the same drive. We can then say that media X is superior for those conditions on that drive. And we may find that media X does consistently better than media Y under a number of different sets of identical testing conditions. Then, we can expand our conclusion to state that media X is generally superior to media Y (keeping mind that there may always be exceptions for specific test conditions).

By the way, Miyuri's notes the readme.txt file of CD Doctor state the same thing - a consumer drive and CD Doctor (or WSES or CD Speed - take your choice) does not make a dedicated, specialized test system, so the results obtained thereby shouldn't be seen as absolute measurements but rather relative comparison data.

Now for a short detour to address a specific comment in cdrfreak’s post:

Reporting correctable C2 errors does not have much practical use.

It depends on one's application. If one is writing CD player software, no it does not have much use, unlike the reporting of errors that are uncorrectable at the C2 level as you rightfully point out. However, if one is trying to gauge the quality of one's CD-R burns, then yes it does have practical use. Forgive me as I again quote myself from earlier in this thread:

A disc may have no uncorrectable errors but have so many correctable errors that it has no margin for further degradation. A little more aging or a small scratch or two may send the error rates beyond the ability of the error correcting codes to correct. Is that the sort of disc to which you want to entrust your valuable data for long term storage? It may work right this moment, but how about tomorrow?

And back to the more general topic:

So, do we yet have a definitive explanation of CD Speed or CD Doctor's measurement and reporting methodology? No. Heck, for all I know there might not even be a single definitive answer since it may depend on what each drive reports from its internal EDC/ECC processes and that may vary from chipset to chipset. So, I will finish with a quote from Ian and one last quote from myself, since I think both are still valid:

The only thing I'm taking from this whole thread is that CD Speed's documentation does not say what its showing in its tests and no one really knows for sure.

Anyone who knows the intimate details of CD Speed's testing methodology, please share with us!

cfitz

* I don't think 'E42', 'E52' etc. is standard nomenclature but rather a logical extension of the original definitions. Accordingly, from here on out I will use 'E32' only, and use it in its original definition of an error consisting of 3 or more bytes with errors passed to the C2 level of error correction.

** CD Doctor does plot is graphs with the label "CPS" which I take to mean "characters per second" - thus, I am assuming the figures are in bytes with errors per second. I suppose it might also mean "corrections per second", which would lead one to conclude that it is only reporting the correctable errors. But this remains speculative at this point.

[Kennyshin]

If you wanted to gain respect on this forum, you would have to observe basic rules first.

Both Inertia and spath are polite enough but it's too easy for anyone to fall into this kind of traps in discussing this kind of issues on public web boards.

I don't think what spath "wanted to gain" was respect here.

I am just glad that people like them are here and post some things.

[KCK]

Kennyshin:

Believe me, writing that post was not easy. Yet nobody else wanted to intervene, and I didn't wish for this thread to end with spath having the final word.

I may just say that if aggressive guys like spath dominated this forum, I would stop attending it.

[Kennyshin]

I may just say that if aggressive guys like spath dominated this forum, I would stop attending it.

If I were you, I'd just say not to be aggressive in discussing technical issues on open forum boards instead of mentioning education and other things. Words and voice can be emotionally or intellectually aggressive to a degee to whom they are communicated. Everyone has one's own world of character and personality and speaks different language. Nobody's here trying to "dominate" this forum (and for what do moderators and administrators exist?)

Frankly, I do not see anything too aggressive here - I saw both of them in the other forum (CDFreaks) and spath is also a moderator there (as me and many others in CDRLabs) which may be I don't read all posts because I am not as accustomed to such long technical discussions in English as they are. I'd also just like to see more plain explanation about what programs like CD Doctor and CDSpeed do.

Believe me, writing that post was not easy. Yet nobody else wanted to intervene, and I didn't wish for this thread to end with spath having the final word.

I know what you mean but not attacking other people IS easy. What spath posted at least contains some things related to CD-R but your posts here are only for criticizing him, rather than what his posts are really about. I did not intervene because of the above-said reasons. I am intervening now because I don't like to see people mentioning about other person's character things when they do not know about them personally.

[KCK]

Kennyshin:

Since our standards on aggressiveness differ, let's agree to disagree.

Moderators:

I am very sorry that my exchanges with Kennyshin have been disturbing this thread. Therefore, if you think it appropriate, and Kennyshin agrees, I would like to ask you to delete my three posts in this thread (including the current one).

[cfitz]

I'd also just like to see more plain explanation about what programs like CD Doctor and CDSpeed do.

Okay, Kennyshin, I will use you as my guinea pig (test subject). I added a very brief and simple explanation of CD Doctor and WSES in the CD Doctor thread at the end of my response to spath's question there:

http://www.cdrlabs.com/phpBB/viewtopic. ... 6820#46820

I think it might be too brief and too simple. What do you think? Does it meet your needs at all? What would you want in an explanation?

Anyone else feeling like they are in Kennyshin's shoes is also welcome to give feedback.

cfitz

[Kennyshin]

I'd also just like to see more plain explanation about what programs like CD Doctor and CDSpeed do.

Okay, Kennyshin, I will use you as my guinea pig (test subject). I added a very brief and simple explanation of CD Doctor and WSES in the CD Doctor thread at the end of my response to spath's question there:

cfitz

Disregard the post please. I didn't really mean it. Maybe I said too much.

@KCK

No.

[Hitokiri]

It is advisable before you presume to tell someone that they are wrong that you understand what they (and you) are talking about.

You seem to have minimal knowledge or understanding on the subject yourself, but have been referencing other people with no quotes or explanation attributed to them. You advise people to contact someone (SatCP) who won't return your own emails. There is nothing on his site regarding this subject. In short, rather than adding knowledge to this discussion you have been dropping names with no accompanying information.

I am terribly sorry I do not live up to your expectations..I am always able to learn about the subject and admitted, I could be wrong..so I'll be more explicit in what I say from now on. I am not an engineer of some sort..and even if i was i would still have things to learn..as do you.

cd speed DOES show E32 errors

Where is your source for this statement, other than your opinion? I said that E32 errors are not measured. You are not understanding the distinction between measuring of E32 errors and the consequence of an E32 error(s) that is uncorrectable by ISO Mode 1 EDC/ECC error correction. The unreadable red block(s) is a consequence of an uncorrectable error, not a measurement. There are no freeware CD testing utilities that measure E32 errors. Burners may have the capability of returning information on C2 error correction, but not consequential uncorrectable E32 errors. Nero CD Speed discloses unreadable areas that may have their genesis in E32 errors that could not be corrected by EDC/ECC. When a file or sector or frame can't be read because of an uncorrectable error, this is not the same thing as reporting an E32 error per se. E32 errors are a technical measurement provided by expensive testing equipment used by manufacturers or testing facilities. They are C2 errors that can't be corrected at the C2 level because there are three errors in the same frame.

I understand what you are saying here now. All I can say is that SatCP claims that Nero CD Speed cannot measure C1 or C2 errors, only the 'uncorrectables' wherefor he uses the term 'E32'. I should add that he has corresponded with Erik Deppe who says that color of the blocks resemble the density of the errors. That is all I know..well not ALL I know.

The Surface Scan can detect damaged areas if the drive can report C2 errors (most current drives do).

To say that all yellow blocks represent E32 errors is equivalent to saying that all C2 errors are E32 errors. This is absolutely false.

Not true. It could be the program reports only E32 errors which both can be and cannot be corrected by EDC/ECC. Your quote does not say the program measures all kinds of C2 errors.

What is this "..ask the author of the program" comment supposed to mean? Does this mean that you have already queried him and know something that we don't? If this is so, please quote his comments or please refrain from making meaningless statements.

It would be very helpful to contact and ask the author himself. In fact, I think I will try and refer him to this topic.

Again, to quote from the CD Speed help file:

The yellow parts show damaged areas. For data CD's the data in these areas can be corrected. The red areas are unreadable. This means files are lost which is also indicated by the File Test.

What does Erik mean with 'damaged'? It could well be that he means that yellow blocks represent E32 errors that can be corrected by EDC/ECC and red blocks represent E32 errors that cannot be corrected by EDC/ECC.

You didn't say what game you have illegally downloaded. If it is a copy protected game as many are, then the red blocks might be explained in this manner:

This is not a discussion about the legality of downloading 'iso games', in fact it is completely legal in certain country's, left alone that one can download a game for backup purposes. I have had it with more than 1 game, examples given: gta 3 and star wars galactic battlegrounds.

If the game is protected by Safedisc, for instance, this protection uses unreadable sectors to verify the CD. These unreadable sectors will show up as red blocks in CD Speed. In order for the MD5 to match, the same unreadable sectors would have to be in the image and the burned copy.

That could well be an explanation indeed, however I do not know if bin/cue's are able to contain these sorts of protections (maybe you can tell me) and I do not know how these bin/cue's are created. It can well be that the disc is copied to hard disk, the fixed exe is created and the dir's are converted to an image file. Now that you mention it..this was my last question to SatCP before he stopped replying..maybe he's dead or something.

EDC/ECC will try to correct errors in a standard Mode 1 (or Mode 2 Form 1) CD-ROM when it is reading the source material. If the source material is a RAW image (2,352 bytes/sector) of a copy protected CD-ROM, this image was not read and would not be written in the standard Mode 1 method which uses EDC/ECC. It was read RAW (no EDC/ECC) and would be written in a RAW mode which exactly copies the image and its unreadable sectors. If this were not done and error correction were applied, the copy protection would be invoked and the game copy would not work.

Fixed executables are used with most 'iso games'.

The following links contain references to error correction technology and terminology:
8<

Thanks for the information, I will read it while thinking of you.

[Pio2001]

Since only drives capable of returning C2 information should be used with CD Speed, we can assume that CD Speed relies on the drive reporting C2 errors.

As monthes and years of testing by ExactAudioCopy users showed, the C2 info returned by the drive for audio CDs are uncorrectable errors .
Tests at cdrinfo.com (like this one for example), and here shows that on many drives, 99 % of the C2 info returned by the drive match a data not read properly, thus an uncorrectable error.
Since these errors can be three, four, or five wrong C2 bytes in a frame, I think that it's better to call them just CU errors, following cdrinfo's writing quality article.

I ran CD Speed quality check on the DAEQuality test disc of Andre Wiethoff (http://www.exactaudiocopy.de/eac13.html).



Drive=Memorex DVDMaxx 1648. I stopped the test before the end, because the drive was completely stuck.
Errors are detected. It confirms that CD Speed can use the C2 info returned by the drive, because in audio, there is no EDC/ECC.

I ran the test again with the Yamaha CRW3200 burner :



The DAEquality analysis showed that this drive couldn't read the test CD without errors either (http://pageperso.aol.fr/lyonpio2001/dae/eacdae/eacdae.htm), but this drive can't report C2 errors. We can see here that, though errors should have occured, CD Speed reported none, because the drive can't report C2 errors. Thus testing audio CDs, Cd Speed can only rely on the drive's ability to return info about C2 errors that couldn't be corrected.

Here are pictures from a CD ROM (test stopped too)

Memorex DVDMaxx 1648 :



Yamaha CRW3200 :


Here, the Yamaha reports errors. It means that for CD ROMs, ECC/EDC are also used besides C2. Otherwise, the Yamaha would have detected no errors.
Red and yellow errors immediately showed up. Therefore yellow errors must be errors detected and corrected by ECC, while red ones would be uncorrected data, that is corrupted files.

There was also a red line after some time in the audio test with the Memorex drive, but it only occured when the drive is completely stuck, making worrying noises, and freezing all the computer (because it shares the IDE of the hard drive, I think). Thus it must be some kind of timeout detection or something like that.