The Compulsive Splicer wrote:
>> CD's are compresses, though lots of people don't know this and the industry
>> denied it for ages (to get CD players fast into the mainstream, hey it
>> worked ;-)
> Please source this claim. I find it very difficult to believe that "the
> industry" could have kept this part of the CD (what is it, Red Book?)
> specification secret all these years.
The "compression" is obvious: there is no infinite amount of values
recorded, it is limited to "only" 44100 data points per second and "only"
65536 different amplitude values at all. Any other much higher
digitalization compresses the analog stream of information into a discrete
amount of digital numbers. The compression is finally done in the CD player
which interpolates the values between two recorded discrete values by a
linear or spline curve.
> Put that together with the fact that I perceive absolutely no need for
> compression to fit the amount of music onto a CD, and I find this claim
> incredible.
I've tried what happens with a AIFF file burned in Audio format but with
lower sampling rate (in my case 22.05kHz) in a normal CD player. It simply
plays as twice as fast and is not useable. But it is feasable to slightly
change the sampling rate from 44.1kHz to e.g. 43.5kHz in order to squeeze
out a minute or two. I've tried this too but I got a distortion with the
difference frequency of 600Hz on all songs, which made the whole try
worthless. The distortion was very likely caused by imperfections of my
audio hardware (not perfect anti-aliasing filters of the built-in Macintosh
audio chip).
-- With best regards / Viele GruesseMarco Mailand http://slsbd.psi.ch/timing
-- This is the Newtontalk mailinglist - http://www.newtontalk.net To unsubscribe or manage: visit the above link or mailto:newtontalk-request_at_newtontalk.net?Subject=unsubscribe
This archive was generated by hypermail 2.1.2 : Thu Nov 01 2001 - 10:02:57 EST