Re: Digital Audio Extraction with ATAPI drives far from perfect

[Jens Axboe <axboe@suse.de>]

On Wed, Jan 04 2006, Jens Axboe wrote:
> On Tue, Jan 03 2006, Sebastian wrote:
> > Hello all!
> > 
> > I'd be kind if you would cc me in case you reply as I'm not (yet)
> > subscribed to this list.
> > 
> > I'm a music buff :) Well, I guess most people are in one way or the
> > other. But in addition to that I like bitperfect ripping very much.
> > Since some time this doesn't work well with linux anymore.
> > 
> > I'd like to know if there's something in the making already or what
> > could be done to solve this issue. A supporting layer for the ide
> > system, a new driver maybe? I think this can't be fixed in userspace,
> > right?
> > 
> > I ripped an audio disc in different ways and compared the results using
> > md5sum. As you can see the wav data is perfect when using ide-scsi
> > emulation. On the contrary, using ide lead to errors.
> > 
> > Linux version 2.6.15 (root@section_eight) (gcc-Version 3.4.4 (Gentoo 3.4.4-r1, ssp-3.4.4-1.0, pie-8.7.8))
> > 
> > In all cases I used the same drive, a NEC ND-4550A dvd writer.
> > 
> > The first series of wav files was ripped with EAC in Windows and is
> > bitperfect:
> > 
> > 8cab5ca4820a753ebb3cb7e3c5c34e6a  01.Man In A Suitcase.wav
> > 187f90f900cffd36ce56e97a3bcf595e  02.Box Of Six.wav
> > 8cc168bb50e80a06693a01a9cd34bbdf  03.Mysterons.wav
> > e82169e5ea1b441b80db96fce12fd109  04.Justified.wav
> > 8d807b7ac19f90049aec6ff177e9b486  05.Department S.wav
> > 130306e9a564c844d5269256f38afca7  06.Area Code 51.wav
> > 96489dbfcab8f97e7e450cf8db2c8aaa  07.Has To Be.wav
> > 4597a6ed75e201916a3479f05eb86405  08.No. 5.wav
> > f978327a98fc6359be2fc25eb865211d  09.Among The Cybermen.wav
> > e316e140b4b0cd66e5822edae22dadb1  10.Unspeakable Elvis.wav
> > 3792a680b1ba729de9185043d331186f  11.Xodiak.wav
> > ba534fd8eb42dd84aa7b59ab3ae6f132  12.Northern Wisdom.wav
> > d6346ab76696dddf735a5b752aa7888b  13.Trinity Road.wav
> > 
> > The second series was ripped with deprecated ide-scsi emulation and yielded the
> > same results as EAC.
> > 
> > The third series was done with ide-cd. Erroneous data is marked
> > with a (!):
> > 
> > e8319ccc20d053557578b9ca3eb368dd  track01.cdda.wav (!)
> > cb978f86ddc18c9df1b7e91705380bc5  track02.cdda.wav (!)
> > 35f1b296d72a8708d03aeb540a3b4f30  track03.cdda.wav (!)
> > e82169e5ea1b441b80db96fce12fd109  track04.cdda.wav
> > 8d807b7ac19f90049aec6ff177e9b486  track05.cdda.wav
> > 02561939763d67aacf23157c09966a89  track06.cdda.wav (!)
> > 9724b0a3e2295084613da9df7397ae6d  track07.cdda.wav (!)
> > c2d85b3d10428aad66664d0fb3e4c71a  track08.cdda.wav (!)
> > 5116b2fae44b8b86fbf40b9bac9a8268  track09.cdda.wav (!)
> > 9e6a5ab2dab76e1677667f586895293a  track10.cdda.wav (!)
> > 3792a680b1ba729de9185043d331186f  track11.cdda.wav
> > ba534fd8eb42dd84aa7b59ab3ae6f132  track12.cdda.wav
> > d6346ab76696dddf735a5b752aa7888b  track13.cdda.wav
> 
> Can you try and see how, say, track01 differ? Is it single bytes, chunks
> of 2352 bytes, or?

Oh, and try and disable DMA on the cd driver and repeat your results
with ide-cd. It uses DMA, where ide-scsi does not. Dunno what Windows
does. It could just be a problem with your drive and DMA enabled rips.

-- 
Jens Axboe