In my original posting, I inquired about reading data from audio
CD's using Sun's CD-ROM player. Basically, I was able to read the
table of contents, but attempts to read the data yielded "I/O Error"
faults. I suspected that there might be some sort of digital read
protection that this CD-player provides for audio discs.
Can anyone confirm/refute this suspicion?
A sample reply (email@example.com):
> The Sony cdrom drive firmware doesn't support reading audio data
> directly from the disk. The subcode information on the disk does
> make a distinction between audio and digital data (even though
> it's really all just bits). My guess is that it is a simple form
> of copy protection.
There was some disagreement as to whether the audio read limitation
was put into the CDROM drive (a Sony device, I think) or into the Sun
Several people indicated that the SGI Indigo *CAN* read audio data.
One person suggested that I try to re-route the audio playback
from the Sun audio port to somewhere else, thereby "capturing" the
audio data for later perusal. However, as far as I can tell, the
CDROM audio playback feature can only work with the headphone jack
on the front of the CD player--data is never routed through the
SCSI interface up to the sun for playback via the /dev/audio port.
If anyone knows differently, please speak up!
The "xcdplayer" software in the X11R5 contrib software works quite
well if you want to use your CDROM drive as a audio CD-player. It
provides a small window control panel for start/stop/track-select/
eject/etc.... The only problem that I could see was that the
volume control slider needs to be re-calibrated to map the quite-
loud range over the full range of the slider. Now all I need is one
of those cordless headphones....
If anyone wants my humble "cdtoc" (table-of-contents) and "cdread"
(read cd track) programs you can grab them via anonymous ftp from
uw-isdl.ee.washington.edu or send me email for a copy. The "cdtoc"
program just lists tracks, min/sec/frames, subcode, etc. The "cdread"
program doesn't work of course, but might be ported to a SGI Indigo
fairly easily :-)
Thanks to the following people for taking the time to reply:
firstname.lastname@example.org (Jeremy Lawrence)
email@example.com (Hal Pomeranz)
firstname.lastname@example.org (Joe McGuckin)
email@example.com (Ken Bibb)
firstname.lastname@example.org (David DiGiacomo)
email@example.com (Guy Harris)
Bernhard.Schneck@Physik.TU-Muenchen.DE (Bernhard Schneck)
Interactive Systems Design Laboratory
Dept. of Electrical Engineering
University of Washington
Seattle, WA USA
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