[PD] cat /boot/vmlinuz-2.6.35-30-generic > /dev/dsp ?

Mathieu Bouchard matju at artengine.ca
Mon Sep 12 20:06:18 CEST 2011

On Mon, 12 Sep 2011, tim vets wrote:

> I would like to get the sound of my kernel into pd. cat 
> /boot/vmlinuz-2.6.35-30-generic > /dev/dsp should be a command I can get 
> the sound of my kernel into the speakers with. However, while I remember 
> having done similar before, right now, on this machine there doesn't 
> even seem to be a /dev/dsp present... also, how would I get this into 
> pd?

the name vmlinuz means something like « virtual-memory linux, zipped », by 
opposition to the original vmlinux files of early nineties. This means 
that the sound will be highly entropic, as an efficient form of 
compression tends to make all combination of bits equally likely. This 
makes compressed files become undistinguishable from white noise.

you get a lot more interesting textures by playing noncompressed files, 
even though their «sampling» scale does not match presumed samples of 
sound : samples of sound are assumed to be 8, 16, 24 or 32 bits each, 
uniformly. Pentium-compatible executables can have such multiples and 
other multiples of 8 bits up to about 120 bits in the same opcode, but 
it's happening in an irregular fashion... each file has a mix of elements 
of various sizes.

However, those executables are still a lot more regular than a gzip or 
zip2 file, which are made by reading pieces of 8 bits and rewriting them 
as a variable number of bits, 3, 4, 5, ..., 9, 10, 11, whatever is most 
efficient. (Well, that's only half of what that compression method does, 
but it should give you a good idea of how scrambled things are already !)

| Mathieu Bouchard ---- tél: +1.514.383.3801 ---- Villeray, Montréal, QC

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