AccurateRipping from virtual drive not supported?

[soundhole]

Hi.

I'm trying to use dMC to rip from an image mounted as a virtual disc. I can take an audio CD, put in in my physical drive, and it will function as a Key Disc without any problems. I then make an image of the audio disc (see below) and mount it on a virtual drive. dMC seems to recognize it as a valid Key Disc because it puts up the message: "This CD can be used to configure AccurateRip" but then it returns the following error:

"This Key Disc cannot be used for offset detection (it does not match the one stored in the AccurateRips database), please try a different Key Disc."

I've tried a number of permutations of:

* Image creation SW: Nero, Alcohol, Roxio, UltraISO
* Image file format: bin/cue, nrg, mds/mdf
* Image virtual drive SW: Alcohol, UltraISO, Daemon Tools

...and they all produce the same error. The strange part is that, in almost all cases, the virtualized audio disc otherwise seems fine. The audio plays and sounds fine, it rips, fetches AMG data, etc. dMC just won't recognize any virtual disc as a Key Disc for AccurateRip.

Am I doing something wrong? Is there something about virtual image drivers that appears fundamentally different to the ripper?

Thanks,

Ken

[LtData]

Re: AccurateRipping from virtual drive not supported?

I believe this is a known problem, but I'm not sure if a solution was able to be found. See here for some discussion on this matter: http://www.audiosense.org/forum/show...=virtual+drive

[soundhole]

Re: AccurateRipping from virtual drive not supported?

OK. That discussion was interesting, but it just narrowed the problem to AccurateRip. Isn't that your software?

I don't quite understand your supposition. The drive itself (and its associated device driver) has an offset that can be different from model to model. If I understand correctly, the first buffer of data read from the drive has prepended garbage, so the offset we're talking about is the number of samples (bytes? 32-bit words?) before the actual audio data begins.

Here's my best guess. In the case of the virtual drive, the image file would begin with the first audio sample just as the audio disc itself. The discussion you referenced seems to confirm this. The problem seems to be that none of the emulated optical drives prepend garbage because they don't have a buffer with modulo addressing implemented in hardware like the physical drives do. I'm guessing that AccurateRip starts guessing that offset starting at 1 on the assumption that it will never see a physical drive with no offset.

This is called "system debugging without ever having seen either a schematic or a line of code." :p

I would also hazard a guess that this issue will come to the programmer's attention when serious work on image ripping begins for R13. The real question is whether anyone will look at the AccurateRip code before then.

Ken

[Spoon]

Re: AccurateRipping from virtual drive not supported?

Why would an image drive prepend garbage to audio data? what is the point?

More likely the TOC is different in the virtual drive.

[soundhole]

Re: AccurateRipping from virtual drive not supported?

Spoon,

You, obviously, would know better than I what the problem might be.

It's an odd bug, though. Programs like Daemon Tools and Alcohol go to great lengths to emulate the behavior of physical drives because they are often used to emulate the idiosyncrasies of copy protected discs. There must be something that AccurateRip cares about that these programs are not emulating correctly on audio CDs. Every other program that handles audio CDs seems to work, though, including all other functions that I've tested in dMC.

I'm just reporting a bug and hoping that it gets fixed eventually.

Thanks,

Ken

[Spice B.]

Re: AccurateRipping from virtual drive not supported?

Also it seems an offset is indeed an order of the day when ripping off the virtual drives. Not only accuraterip doesn't recognize a valid key disc as a key disc (I've tried about 20 already), but the very first ripped song of a CD image has a loud and irritating "tick" sound in the beginning. Has anyone else noticed the same, or am I the only one? Thanks.

[mange]

Re: AccurateRipping from virtual drive not supported?

Works for me

Making the image file with nero
mount it with deamon tools
accurate rip offset calculating and rip

tried twice

[Spice B.]

AccurateRipping from virtual drive not supported [Update]

Just would like to update my previous comment. Earlier I was using Magic Disc to mount disc images. After I installed and started using Alcohol 120% instead, accuraterip not only began to identify the key discs that it, earlier, was rejecting, but also calculated an appropriate offset for the virtual drive. However, a new issue has now appeared. Even though accuraterip is now properly configured, it shows "inaccurate" rip message when dbpoweramp ripper is used. However, the case is not the same when I use EAC. Accuraterip works like a dream in that case. I don't know if I need to tweak some settings to get it right with dBpoweramp ripper. I am half-way through. Need some help cover the rest of the distance. I would love to use dBpoweramp ripper instead of EAC. I just love the AMG feature in it.

[LtData]

Re: AccurateRipping from virtual drive not supported [Update]

Do dMC and EAC show the same AR offset?