On Mon, Mar 24, 2008 at 02:12:48PM -0700, Lan Barnes wrote:

The fact that cdparanoia has paranoia makes me wonder how necessary it is.
While the time waiting for one's tracks to rip is slow, the time ripping
bad tracks quickly is wasted. and one wouldn't know without trying them
all.

When cdrom drives first came out (think 1X), they basically were audio CD
players with some extra hardware processing the output.  Each audio frame
contains an additional layer of ECC and includes the sector address, when
read as data.  But, to read the direct audio, the addressing information
doesn't come through.  Issuing the command to read raw audio would return
audio data starting approximately where requested, but it wasn't precise.
Programs like cparanoia were needed to recombine the audio data (basically
doing overlapping reads and figuring out what the overlap was).

It's been completely unnecessary for about 10 years now.  Any drive that
reads at a higher speed isn't just a modified audio player, and will have
accurate addressing.  Most now use that addressing information to read
audio data precisely.

If you rip with cdparanoia -Z it will either work fine, or you'll get
massive amounts of skipping.  It is unfortunately still necessary, because
there apparently are still plenty of cdrom drives with broken firmware.

The cdparanoia faq gives some useful information
<http://xiph.org/paranoia/faq.html>, especially why getting the accurate
positioning is hard for the drive to do.

David


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