Question about USIng Nero CD SPEED

[AmdMaster]

Is this a reliable testing program for testing the quality of Software CDs or is this just for CDR's? I just decided for the fun of it it to Scan a orginal Software application called NortonsSystem Works 2000. The Strange thing I noticed is that the whole disk was damaged.
For Christmas I purchased the Windows xp oem for the home. IF I use CD Speed to scan the quality of disk and it comes up damaged, You think Microsoft Would take it back with no questions asked, if it was a legit copy of windows xp oem. Or should I go through the online retailer I purchased it from. I am just thinking worse case scanario. I didn't open my presents yet.

thanks for the help

[ryus]

Also, can someone please explain how to use NERO's c1/c2 error checking utility?? And also if you can explain how to read the results of the lines/graph.

Thanks.

[Hitokiri]

no, it's not reliable..check my reply in this thread:

http://www.cdrlabs.com/phpBB/viewtopic.php?t=8190

[ryus]

I dont mean the "Surface Test", the one with the green, yellow and red squares. I meant for the "CD quality Test". How do you interpret those results?

[Hitokiri]

the higher the graph, the more E32 errors are on the disc..i think it's quite the same as the scandisc option, only here it also shows you how fast your disc was read..the faster, the less errors

make sure to use a high quality drive for interpretation

correct me if someone believes i'm wrong

[cdrfreak]

no, it's not reliable..check my reply in this thread:

http://www.cdrlabs.com/phpBB/viewtopic.php?t=8190

Saying CD Speed is unreliable because it only reports uncorrectable C2 errors is nonsense of course.
Uncorrectable C2 errors are the ones most people (should) care about.
If there are no uncorrectable errors on the disc it means that every single byte can be retrieved which means you have a good disc.

[cfitz]

Errors are correctable at the C2 level. This may be semantics, and my usage of the term may not be the common usage, but if an error isn't correctable, then I don't consider it to be a C2 error. I only consider errors correctable at the C2 level to be C2 errors. It would then follow that there is no such thing as an uncorrectable C2 error.

I would still like to know the exact details of what CD Speed's CD Quality Test reports. Unfortunately, the documentation only states that it graphs "errors", and as is evident, there are many different types of errors with differing severity and consequences. I believe that CD Quality shows errors that are uncorrectable (E32) in red, errors that are correctable at the C2 level of error correction (E12 and E22) in yellow, and doesn't show errors correctable at the C1 level of error correction (E11, E21 and E31) at all.

Utilities such as WSES and CD Doctor ( http://www.cdrlabs.com/phpBB/viewtopic. ... 5549#45549 ) can report C1 level errors.

If there are no uncorrectable errors on the disc it means that every single byte can be retrieved which means you have a good disc.

Not true. 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?

Anyone who knows the intimate details of CD Speed's testing methodology, please share with us! Also, anyone who knows the definitive semantics for errors (i.e. is an uncorrectable E32 error called a C2 error or not?) please let us know.

cfitz

[Inertia]

cfitz,

I basically agree with your assessment, but without knowing intimate details of CD Speed testing methodology or definitive semantics of errors this is my take on the subject:

C2 errors are errors that can't be corrected at the lower C1 level. An E32 error is not an error correction level as C1 and C2 are, but is just a measurement of error frequency at the C2 level.

CIRC (Cross Interleaved Reed-Solomon Code) is the basic error correction code used by CD's and CD-ROM's for C1 and C2 error correction. Errors may or may not be correctable at the C2 level. The CIRC error correction in CD's and CD-ROM's at the C2 level can correct errors in two bytes per frame (E22 error). A third C2 byte error per frame is an E32 error, which is uncorrectable by CIRC. E32 errors are not permitted in the manufacturing of CD's and CD-ROM's by the Red Book specifications.

The third level of error protection for data discs in ISO Mode 1 (EDC/ECC) may or may not be able to correct the E32 or E42 errors which are uncorrectable by CIRC. This is the "last chance" at error correction for critical data, but is far from fail-safe.

I don't think that E32 errors are measured by the CD testing utilities that we play with. If E32 errors are corrected by EDC/ECC, then it's just a C2 error corrected at a higher level (yellow block). If E32 errors can't be corrected, then sectors are unreadable and files are lost. This is when the red block appears in CD Speed ScanDisc.

In my experience, a data CDR which has severe C2 errors when read at 48x may have no C2 errors when read at 8x. The burned media does not stand alone as a measure of quality. The interaction of read speed and reading device can produce different results which may appear to raise or lower quality. Without expensive laboratory equipment, a home user is not able to do definitive media quality testing. The best one might hope for is to find media that produces low errors over a wide range of speeds/conditions and works reliably in the devices available for testing.

[cfitz]

In my experience, a data CDR which has severe C2 errors when read at 48x may have no C2 errors when read at 8x. The burned media does not stand alone as a measure of quality. The interaction of read speed and reading device can produce different results which may appear to raise or lower quality. Without expensive laboratory equipment, a home user is not able to do definitive media quality testing. The best one might hope for is to find media that produces low errors over a wide range of speeds/conditions and works reliably in the devices available for testing.

Absolutely. I have said the same thing in the media compatibility thread - the results we see are a function of the writer, reader, media and a host of other variables. So, we can't specify the absolute quality of media X, and, in fact, it doesn't even make sense to try. At best one can say media X performs at some level under some conditions.

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).

Which all pretty much boils down to what you said.

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.

cfitz

[Inertia]

AmdMaster,

CD Speed is a reasonably reliable program for the testing of CD quality. It has so many features and has undergone so much development over the years that occasionally a glitch or two will appear as with any software.

Some users have unreasonable expectations when it comes to the measurement of CD quality with this excellent freeware program. When the same error measurement result is not repeated exactly, this is construed to be an unreliable result. In fact, the different result is probably produced by hardware making assessements of data validity and errors. This assessment may change when a test is repeated because reading is basically an analog process using a statistical decision. This is eloquently explained by cfitz in Help with CD Speed.

Considering all of the testing capabilities that it has, CD Speed is one of the best general purpose CD performance testing programs available.

[Inertia]

I dont mean the "Surface Test", the one with the green, yellow and red squares. I meant for the "CD quality Test". How do you interpret those results?

The CD Quality Check lets you see how a drive recovers from CD read errors. If the the green line stays constant, then the disc is being read efficiently. If the green line dips to a lower level and starts reading again, this is a strategy readers use when errors are encountered. The read speed is lowered until the area with errors can be read successfully.

If there are yellow spikes, these are C2 errors with the relative amplitude reflected in the graph. The number of errors is reported at the bottom.

[Hitokiri]

If there are no uncorrectable errors on the disc it means that every single byte can be retrieved which means you have a good disc.

Not true. 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?

exactly!

Anyone who knows the intimate details of CD Speed's testing methodology, please share with us! Also, anyone who knows the definitive semantics for errors (i.e. is an uncorrectable E32 error called a C2 error or not?) please let us know.

cfitz

i would say SatCP, definitely..try mailing him sometime

[ryus]

Thanks Inertia!!! for explaining "that" graph!!!

Also thanks to everyone else who provided insight and knowledge to this error topic!!

[Hitokiri]

I don't think that E32 errors are measured by the CD testing utilities that we play with. If E32 errors are corrected by EDC/ECC, then it's just a C2 error corrected at a higher level (yellow block). If E32 errors can't be corrected, then sectors are unreadable and files are lost. This is when the red block appears in CD Speed ScanDisc.

sorry, i must have read over this but i must say that you are quite wrong here
cd speed DOES show E32 errors..the yellow and red color only resemble the density of errors..ask the author of the program

as i said in another topic, sometimes when i burn a downloaded bin/cue of a game, cd speed shows me red blocks when performing scandisc on the disc..if files were really damaged..my md5 would not match, but it does
i don't quite understand where you are heading at, since you said it yourself that when burning files, EDC/ECC will try to correct these errors anyway..

[Inertia]

I don't think that E32 errors are measured by the CD testing utilities that we play with. If E32 errors are corrected by EDC/ECC, then it's just a C2 error corrected at a higher level (yellow block). If E32 errors can't be corrected, then sectors are unreadable and files are lost. This is when the red block appears in CD Speed ScanDisc.

sorry, i must have read over this but i must say that you are quite wrong here

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.

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.

..the yellow and red color only resemble the density of errors

You seem to be saying here that the yellow and red blocks are E32 errors which differ only in the density of the errors. As I have stated, E32 errors are not being reported, only damaged but corrected areas (C2 errors) or unreadable areas. These yellow blocks have a close correlation to C2 errors reported by testing programs like CD Doctor. To quote the Nero CD Speed help file:

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.

..ask the author of the program

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.

as i said in another topic, sometimes when i burn a downloaded bin/cue of a game, cd speed shows me red blocks when performing scandisc on the disc..if files were really damaged..my md5 would not match, but it does

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.

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:

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.

i don't quite understand where you are heading at, since you said it yourself that when burning files, EDC/ECC will try to correct these errors anyway..

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.

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

CD/ROM -- An extension of the CD audio standard

CD Testing: The Digital and Analog Sides

Compact Disc Testing

Testing, Testing. . .CD-R

[spath]

> 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.

Amongst others, CDSpeed does show uncorrectable errors in
its Advanced DAE Error test. Any drive which supports
the C2 pointers feature can give you the location of C2
uncorrectable errors (which nowadays are mostly based on
E52, not E32).

[Inertia]

spath,

Uncorrectable DAE errors by definition are uncorrectable C2 errors on an audio CD without the benefit of EDC/ECC error correction. In its audio disc test, CD Speed ScanDisc also reports uncorrectable C2 error areas. Correctable C2 errors on an audio CD are not reported, only damage due to uncorrectable C2 errors. It is rare to see unreadable areas on an audio CD.

When Mode 1 data is recorded on low quality media, the CD Speed test may report many damaged but correctable areas. Using the same low quality media for an audio recording may show no errors.

Yes, any reader that returns C2 errors is able to report where uncorrectable errors occur. This is what CD Speed is doing, and without this capability we wouldn't be having this discussion. What it doesn't give you is exactly what type of uncorrectable error is present (E32, E42, E52). The ability to correct the more severe errors depends on the correction capabilities of the reader.

The main thrust of the discussion in this thread has been the error correction and reporting of Mode 1 data discs. When the EDC/ECC capability is used with a data disc, its higher level error correction capability is increased by several orders of magnitude (approximately 10³) compared to an audio CD.

[spath]

> What it doesn't give you is exactly what type of uncorrectable error
> is present (E32, E42, E52).

First of all, E32 and E42 are now corrected by most drives' CIRC,
so if you want to discuss technical topics you should update your
figures. Second, complaining that CDSpeed does not give you the
type of uncorrectable errors does not make sense. If C2 stage can
correct 4 wrong bytes and you get uncorrectable errors then you
cannot know how many bytes >4 are wrong ; this is a limitation
of Reed Solomon algorithm and no tool will give you this information.

[Inertia]

> What it doesn't give you is exactly what type of uncorrectable error
> is present (E32, E42, E52).

First of all, E32 and E42 are now corrected by most drives' CIRC,
so if you want to discuss technical topics you should update your
figures.

You have left your nitpicking heaven at CD Freaks to bring your attitude here. If you want to split hairs and nitpick on technical topics, please present the reference data to support your claims so that we can all benefit.

Second, complaining that CDSpeed does not give you the
type of uncorrectable errors does not make sense.

Obviously you are trying to pick a fight with me. "Complaining" - this is absurd. You either haven't read this thread or you don't understand what you read. I was refuting a previous argument that CD Speed returns only E32 errors. I stated that CD Speed does not return uncorrectable errors by type but by an unreadable condition. I further stated that CD Speed was one of the best general purpose CD performance testing programs available. Far from complaining, I was supporting the results of CD Speed.

If C2 stage can correct 4 wrong bytes and you get uncorrectable errors then you cannot know how many bytes >4 are wrong ;

For a given reader, how do you know how many error bytes more than 2 can be reliably corrected at the C2 stage? Some readers can correct more than others, but how is this predicted and quantified in a useful and reliable way? Where are these facts published?

this is a limitation of Reed Solomon algorithm and no tool will give you this information.

I have already stated that no freeware utilities will measure uncorrectable errors by error type. This can be done only by expensive testing equipment. You don't realize that you are supporting and agreeing with what I have already stated.

[aznjosh]

i just copied Jedi Outcast with clone cd and it showed all yellow lines and it said there were 1650 errors on the cd.

[spath]

> You have left your nitpicking heaven at CD Freaks to bring
> your attitude here.

Actually I came here for a precise (still unanswered) question
about CDDoctor and looked at this thread just out of curiosity.
However, I'm always happy to expose people who like to explain
others that they have "minimal knowledge or understanding" on
technical topics, and then show the next line that they themselves
have no clue either.

> If you want to split hairs and nitpick on technical topics,
> please present the reference data to support your claims
> so that we can all benefit.

This is not hairs splitting, but very basic and important
prerequisites you have to know before discussing CIRC. If
you're interested in theory, search for Reed Solomon erasures
decoding. If you just want to be convinced, go download
datasheets from sony, philips, sanyo, etc

> For a given reader, how do you know how many error bytes
> more than 2 can be reliably corrected at the C2 stage?
> Some readers can correct more than others, but how is
> this predicted and quantified in a useful and reliable
> way? Where are these facts published?

Open the drive, find the channel decoder chipset and
download its datasheet. For a practical method, you can
try http://pageperso.aol.fr/lyonpio2001/dae/dae.htm

> I have already stated that no freeware utilities will
> measure uncorrectable errors by error type. This can be
> done only by expensive testing equipment. You don't realize
> that you are supporting and agreeing with what I have
> already stated.

Errr, not at all. The cost of equipment is irrelevant here.
Again, this is an _algorithm_ limitation, so no tool will
tell you if your CIRC gets 5, 7 or 9 uncorrectable C2 errors.
Got it ?

[Inertia]

Thanks for the info and gratuitous insults. The audio error correction experiments that you reference were posted on the Web less than a week ago. Presumably, this is your pretext for your snide comment:

First of all, E32 and E42 are now corrected by most drives' CIRC, so if you want to discuss technical topics you should update your figures.

I don't think anyone is going to follow your impractical advice on downloading the datasheet for a channel decoder chipset. In case you haven't noticed, this is not a technobabble forum which is your natural habitat. Also, I have to keep repeating that the questions in this thread being addressed were regarding CD-ROM error correction for data discs, not audio.

I make no claim or pretense of being an expert, and those of us at CDR Labs who don't have a clue are always honored to have a World's Greatest Authority lurking and waiting to spring upon us with overweening arrogance. I am happy to be "exposed" by the likes of you. I will let the readers of these forums decide who is more useful and practical for the discussions and problems at hand.

Your profound insights, impractical advice, and off topic tangents will be quickly ignored.

[spath]

> I don't think anyone is going to follow your impractical advice
> on downloading the datasheet for a channel decoder chipset.

Interesting. So if downloading a few pdfs and searching for
"correction" is too difficult for you, how are people supposed
to prove you that you're wrong ?

> In case you haven't noticed, this is not a technobabble forum
> which is your natural habitat.

Hehehe, for you information these "technobabble" things are
what allows you to play and burn your discs. Now if you're
not interested in this field, then don't try to impress others
with "technobabble" arguments.

> Also, I have to keep repeating that the questions in this
> thread being addressed were regarding CD-ROM error correction
> for data discs, not audio.

For your information CIRC is exactly the same for audio and data,
so audio or data does not matter when discussing C1/C2 correction.
And again, _you_ chose to talk about CIRC, C2, E32 etc, not me.
So if you want to use these words on a public forum, be prepared
to be corrected when you're wrong. Or if your ego can't stand to
be corrected, just talk about topics you really know

[Inertia]

Ladies and Gentlemen,

Please give us a round of applause for spath, the illustrious moderator of the CD Freaks Optical Technical Discussion Forums.

This forum is described on CD Freaks as follows:

This Forum is only for experienced users. The postings here might go in depth and be very technical and not understandable for normal users. Please only use this forum for in depth technical stuff.

As might be deduced, this forum is dedicated to wannabees trying to impress each other with how smart they are. The unwary or unprepared will find this haven of hairsplitting, nitpicking and quibbles a hostile place. It would be a perfect place for an idiot savant. I stayed very clear of the place, making only one post at Is this feasible to create perfect 1-to-1 copies everytime?. This thread covered the masterfully deep and important technical question of making a perfect 1 to 1 copy of a CD by using a scanner!

spath has broken his own rules and brought his antagonistic genius to us unsuspecting and unprepared "normal" people. And all just to "correct" me. From his cloistered world, he is unaware that even the most knowledgeable of members here make no pretense of perfection and freely admit mistakes and willingness to be corrected and learn from each other. It seems common for these technobabble pseudosages to underestimate others. If there is an ego issue, it is quite likely to be his as manifested by his gloating when he thinks he has made a point.

[spath]

Inertia, why can't you stay on topic and answer on the technical
points you yourself raised ? First you asked for evidences that you
were wrong, then refused to look at them, and instead of admitting
your mistakes you're now trying to attack my credibility. This not an adult way to handle a discussion, and it does not make the thread any better.

If by wanabees you mean people who try to impress others with
words they don't understand, then I see no other wanabee in this
thread than you. As for correcting others, I usually feel confident
enough to do so on cd related technical topics, since designing
drives has been my job for quite some years now. And usually people
are happy to be corrected and learn something new, which apparently
is not your case.