On Sat, 2004-01-10 at 19:19, Ted Gould wrote:
> On Fri, 2004-01-09 at 10:06, Craig White wrote:
> > often times, the music isn't heard when played from a CD because the
> > audio cable from the cd drive isn't plugged into the motherboard sound
> > or the sound card in the PCI/ISA slot.
> > 
> > Once you have verified that the cable is indeed in place, you need to
> > verify that the 'sound' mixer has a volume setting and isn't muted for
> > the cd sound input.
> > 
> > If you still don't have sound, then you have to begin the process of
> > tracking the problem down via modules - I got the impression that SuSE
> > handles all of this for you.
> 
> Okay, I'm replying to this e-mail in the chain, just because I think
> everything is getting a little muddy further on.
> 
> The GNOME-CD player will not pull the data off of the drive and put it
> into the sound card.  Yes, this is annoying.  Many computers do not
> connect the sound from a CD-ROM to the sound card - for various
> reasons.  I don't know that they are good ones, but they do this none
> the less.  I'm quite sure that both Mac OS and Windows deal with this
> gracefully.
> 
> Why isn't this done properly in GNOME-media?  Well, mostly because of
> lack of time.  There is a Solaris patch to fix this in bugzilla, but
> I've denied it because it works around where GNOME-media should be going
> - to be all Gstreamer based.  So what really needs to happen is there
> needs to be a Gstreamer input plug-in written that pulls data off of the
> drive - then it can go through the rest of the pipeline.  I believe
> there is one started, I'm not sure it's complete.
> 
> I'm not sure about other Linux CD players - I imagine that there is one
> out there that can pull the data off of the drive and play it.  Perhaps
> the KDE cd-player will.  I can only confirm that today, the GNOME one
> will not.
----
I thought that we covered this earlier but perhaps we haven't.

The standard is to have an audio cable directly from the cd drive to the
sound hardware to play audio cd's without any need to access the bus,
bus interrupts, the processor and enough RAM to cache the data. 

There exists a lot of hardware which deviates from the standard and this
hardware is supported by Windows either because the hardware vendor has
written the code necessary for Windows to use this hardware and either
distributes it with the hardware or if they pay the price for Microsoft
Certification, can be part of the Windows distribution on CD (or cabs on
the hard drive).

Modems have been a primary candidate for this because a modem is
relatively slow, gets exclusive use of an interrupt, and doesn't use too
much cpu cycles and thus, instead of handling the entire process in
hardware, the operating system can handle it in software. This allows
the manufacturer to reduce his cost by providing less hardware.

Similarly, network adaptors, video display adaptors, sound adaptors and
apparently cd-rom drives are adopting proprietary interfaces to allow
cheaper hardware to work with Windows operating systems. Virtually all
laptop computers will choose non-standard type hardware in order to
lower cost and to reduce the amount of chips, thereby reducing power
requirements.

The manufacturers of proprietary hardware have the option of making
their hardware known to the open source community either by releasing
the necessary source code to access their hardware or by releasing
patches or modules for Linux and/or BSD users. Of course, they could
decide that the market is insignificant and not make anything available.

It's clear that in the server hardware market, all of the major intel
based server vendors are choosing hardware that is supported by Linux.
So the problem's are seen in the consumer market where the pricing
pressure is severe and many of the component choice decisions are made
based upon price and not universality. Bottom line, if Linux is the
target, good hardware choices will make things a whole lot easier to
make things work.

Anyway, you are asking about Gnome and Gnome's CD player but I think the
problem isn't Gnome, but rather a vendor's decision to either save 20
cents on the audio cable or by choosing a cd device that doesn't have
the standard audio interface.

Either way, I'm quite sure that the program 'grip' can get the audio
data off the drive and get it written into at least ogg format if not
mp3 or wave format.

Craig