Some of you may remember my thread from a couple of months ago in which I angrily posted about the Milk Inc. - Walk On Water European CD single that I ordered online, only to later discover that it was copy-protected. Despite all my attempts at getting the damn thing to play and rip in my computer, I could never get it to work.

Just last night, I bought a new CD from my workplace. It's a dance compilation (produced in Canada) known as EuroMix 8. One of the first things that I noticed about it was a warning on the back of the case which is as follows:

WARNING: THIS CD IS COPY PROTECTED AGAINST UNAUTHORIZED COPYING. THIS CD IS NOT PLAYABLE IN PC OR MAC COMPUTERS. IT IS ALSO POSSIBLE THAT THIS CD WILL NOT PLAY IN ALL DVD PLAYERS. ALL RIGHTS RESERVED.

I was somewhat surprised by this, since this was the first locally available CD I had seen with a copy protection warning. Anyway, since it had a nice selection of tracks and would be a good item to experiment with, I went ahead and bought it.

As soon as I took off the shrink wrap, I opened up the jewel case, took the CD out and took a close look at the bottom surface. I could see no visible data ring near the outer edge of the disc. This led me to believe that whatever protection this disc had, it was not the same as the one used on the Milk Inc. CD single.

Upon trying the CD out in my computer, I found that my Lite-On LTD163D DVD-ROM drive would not detect the disc and would simply stop reading it after a few seconds. My AOpen CRW-2440 CD-RW drive, however, performed differently. It detected the disc (with all its tracks) and played the tracks on my PC... but it seemed to occasionally pop or skip. Hmmm.

I loaded up EAC and did a test rip using my AOpen drive in secure mode without caching and with C2 error correction enabled. From the moment that EAC started ripping the track, the error status indicator lit up constantly. After the test rip reached about 10%, I canceled the process and listened to the partial WAV file in Winamp. Much to my disappointment, I noticed pops and clicks in the WAV file that were not on the actual CD (when used in a regular CD player). By this point, all indications pointed to SafeAudio copy protection at work.

Attempting to rip the CD in burst mode is no better (if not worse) than the results I get in secure mode with C2 error correction enabled. The DeGlitch program, which apparently is supposed to fix the effects of SafeAudio, seems ineffective on the test WAV files that I've produced from the EuroMix 8 CD.

Damn! At this rate, I'm going to have to invest some money in a device with digital optical out and a sound card with digital optical in to be able to deal with this copy protection BS once and for all. I'd be content with using line-out >> line-in for temporarily getting around the protection, but neither of the copy-protected discs that I own manage to play in my iRiver SlimX or ChromeX. I've notified iRiver about this and have even sent them a copy-protected CD in the hopes that they can release a future firmware update to address this growing problem.

I really can't think of much else to say right now. I'm disappointed that I'm unable to generate proper audio rips from the EuroMix 8 CD, but with the right hardware, it can surely be overcome. In the meantime, I'll have to settle with listening to my copy protected CD(s) on my Panasonic mini-system as opposed to hearing high quality MP3's of them in my portable MP3 / CD players.

You didn't mention whether you enabled "use C2 error information for error correction" checkbox or not. If you didn't do it try again with it enabled. It should fix the clitches in the audio.

Both of the C2 options were enabled... but still, no success.

If I remember correctly C2 correction needs drive to support gap detection B. I haven't tried the option with copy protected CDs as I don't buy those, but it did correct clicks on one unintentionally scratched CD I tried it with.

Hummm... AFAIK, Mr. Bryant created DeGlitch to repair wave files ripped from badly scratched CDs, not to circumvent copy protections.

BTW, he told me he used a very scratched version of "Abbey Road" he has to tune DeGlitch, not some kind of copy-protected CD.

Regards;

Roberto.

Have you tried looking at the CD with the alternate CDFS.VXD ?

ß

Isn't there an SPDIF internal output on your drive, just next the analog output, but with two pins instead or three ? If there is a matching digital CD input on your soundcard, you're OK.

DeGlitch was designed for scratched CDs, but copy-protected ones should produce the same types of errors, just not in the same patterns. I extensively tested DeGlitch with the The Fast and The Furious soundtrack and it worked perfectly.

However, it is important that the data that DeGlitch gets has not been changed in any way. So, obviously any sort of lossy compression is taboo, and even any other sort of C2 correction could corrupt the process. If you are going to try DeGlitch, I would recommend turning off all C2 correction and using burst mode.

If this doesn't help, I would very much like to see the .wav data and maybe I can figure out why DeGlitch is failing. If you could losslessly compress 20 seconds or so and post it somewhere (or even e-mail it to me) that would be great. BTW, WavPack is a nice lossless compressor.

For what it's worth, my AOpen CRW-2440 drive has always been set to gap detection method B.

Well, Roberto, the readme.txt file of DeGlitch does contain the following text:

DeGlitch is designed to detect and correct isolated bad samples in digital audio files caused by ripping damaged CDs or discs that do not meet the CD standard (i.e. copy protected).

The alternate CDFS.VXD work-around is only an option on Windows 9X systems. Since I'm running Windows XP Pro, I cannot test out the alternate driver to see if it would take care of this copy protected CD.

I think you're missing the picture. Although I can get the CD to play on my computer (through the AOpen CRW-2440), it still suffers from the pops and clicks generated by the protection. What would be the point in using the SPDIF internal output of the optical drive if the drive falls victim to the copy protection? The fact that my Sound Blaster Live! Value sound card has no digital optical in is yet another issue.

Until I buy a stand-alone DVD player with digital optical out and a Sound Blaster Audigy (or Nomad Jukebox 3) with digital optical in, I'm pretty much screwed when it comes to copy-protected audio CD's.

The reason this might work is that the SPDIF outputs of a CD-ROM drive are after the error concealment process (right before the DAC), whereas ripping is done before that step. This is probably because the circuits that perform this function are only designed to work in realtime. You can check this by listening to the CD via the analog outputs of the drive (like through the front panel headphone jack) and the clicks would be concealed if this is so.

However, the fact that you don't have a digital input makes this moot.

BTW, your latest posts make it sound like you missed my previous post.

Heh, I was gonna save your post for last, bryant. Rest assured that I have already tried ripping some tracks from the EuroMix 8 CD with burst mode; my experimentation was not limited solely to secure rips with C2 error correction.
What I've noticed is that, even in burst mode, EAC cannot seem to get a clean read on any single track without encountering what it calls "timing problems." As a result of this, I'm not sure that any sample I could rip and send to you from this CD would be a valid one for analysis purposes.

I purchased the AOpen CRW-2440 because of its apparent ability to overcome Cactus Data Shield CDS-200 protection, according to this online article. Unfortunately for me, I blindly assumed that success against CDS-200 would result in proper rips through other forms of copy protection like Cactus Data Shield CDS-100 (Milk Inc. - Walk On Water) and SafeAudio (EuroMix 8), but this turned out not to be the case.

By the way, your last response about the way a CD-ROM drive works was very interesting. I guess I was the one who was missing the picture.

Well, I have found that the "timing problems" in burst mode usually don't mean anything, but I guess it could depend on your drive. However, if the tracks sound like all the music is there (i.e. no "skips") but simply have clicks added (even loud ones), then there might very well be something that I could do. It's your call...

Hmmm, okay, I'll consider your offer.

Just a few moments ago, I hooked up the analog audio connector from my sound card to my AOpen CRW-2440 drive. I then changed the setting from within the Windows XP Device Manager so that digital CD audio would be disabled for the device. Lastly, I hooked up a set of headphones to the speaker jack on the front of the drive. Upon playing the EuroMix 8 CD through Windows Media Player, all I heard was the mechanical noise that the drive was generating. After playing the CD in Winamp, I could hear the audio coming through the optical drive, but (much to my disappointment) the pops and clicks were still there. Is it essential that I use the SPDIF output of the optical drive to hear the error-corrected audio through the front headphone jack?

No. If you hear the clicks through the CD drive's headphone jack, then I would say that the drive does not have error concealment at all. I have never heard of that, but nothing else makes sense.

Unless we can get DeGlitch to work with those files you're not going to be able to use that drive, I suspect.

Hmmm, okay. Using EAC's burst mode, I'll rip one of the the quieter tracks from the CD so that it'll be easier to hear the pops and clicks that occur within the music.

I still wonder whether these rips can be trusted, however, considering that the warning label on the back of the CD packaging states the CD cannot even be read in a PC. In any case, I guess this testing is worth a shot. Let me know how you want the sample WAV file(s) sent to you...

Great!

The easiest thing would be if you could choose about 20 seconds that has a lot of clicks (preferably with some soft and some loud music), WavPack it, and post it somewhere or just e-mail it to me (david at wavpack dot com). If you regularly use some other lossless compressor, that's fine too (but WTF!? ). Be sure to turn off all C2 options and burst mode is fine (assuming it sounds the same as secure).

I'll be able to tell pretty quickly if there's something that can be done.

Thanks...

What's the largest attachment size your e-mail server can handle? I've chosen a good audio portion that contains a gradual transition from soft to loud music. The file is 0:56 long and is 6.32 MB large using WavPack's high compression mode. I don't mind sending it, but is your server going to accept an attachment of that size?

There are plenty of audible glitches in there, but DeGlitch (interestingly enough) reports 0 glitches found. ???

I can't find a per-message limit, but my total limit is 40 meg, so go ahead and try it and we'll see what happens.

DeGlitch will only detect glitches that fit a very specific characteristic, which is why it's so good at not triggering on the music (as you can see here). I'll be very interested in seeing what those glitches look like.

Thanks for the sample. Unfortunately, the verdict is not good. That sample has missing audio data at those glitches. Not enough that you hear any missing music (like a skip), but there’s a discontinuity in the waveform which results in a “pop”. I thought this might be happening when you kept calling them “pops”, because the glitches caused by just wrong samples don’t have any low frequencies and sound more like “click” or even “tick”.

I have no idea how their copy-protection is getting your drive to drop data like that, especially through the headphone jack. But there’s no way that a program like DeGlitch can fill in the missing data. Sorry...

Hey, that's alright. Even if this CD can't be "deglitched," at least we now know a little more about this copy protection. I wasn't really expecting very positive results, since (as I said earlier) the CD isn't even supposed to be readable in any CD-ROM drive. While I'm can't say for sure that the protection used is SafeAudio, the results I've noticed sound a lot like the "timing" symptom that Macrovision describes in their SafeAudio overview:

Timing Protection Feature

The 'timing' protection feature offers maximum security across all tracks by disrupting the workings of ripping and copying software. Attempts to rip or copy music protected with this feature on a conformant drive will either result in the attempt failing, or will result in the music 'jumping' or being distorted. This optional feature may be used on a single session or multi-session CD.

As soon as I get the required hardware for a digital optical out >> digital optical in connection, I'll never have to worry about this stuff again. Thanks for your interest in this matter, David.

Be advised that, on some copy protected CD's , the SCMS Bit is set to "copy" already ... if your soundcard doesn't allow to ignore this SCMS-Bit, you cannot copy via SPDIF ... I own a TerraTec EWX24/96 which has excellent analogue line inputs as well and can be switched to ignore SCMS information ... ;-) ... I paid 180 € for that card but this investment was really worthy due to no more drama with copy protection PITA (Pain In The Ass, That Is) ...

Greetz

JeanLuc

Hi... I've dealt with copyprotected cd's to some degree. mostly Cactus Datashield. Here's how I used to rip them:

* Grab a copy of clonecd & another of daemontools.
* create an image of the cd with clonecd (audio).
* mount the image with daemontools, now your cd is a virtualcd on your HD.
rip it with your favourite ripping program. This rip is not secure, but it beats analog or digital recording rips...

That's how I used to do it. But a cd that I couldn't read before, my pc suddenly plays... weird. Only 2 things that have changed recntly is that I updated Windows XP > SP1 & that I installed Vob Asapi (ASPI). I'm stomped )

@Negative Zero: The CD you just bought sounds tough but for the older one (Walk on Water) since you say it's using a data ring on the outside for copy protection... you should really be using the marker trick.