[comp.lang.postscript] Rll compression etc.

woody@chinacat.Unicom.COM (Woody Baker @ Eagle Signal) (07/30/90)

In the past, there have been many requests for compressing
bitmaps for transmission to postscript printers.  The general
opinion is that the overhead for the interpreter to decompress the
bit streams, is such to make this unfeasable.

I may have the cure for that.  If someone has a nice SHORT compress/decompress
routine written in 'C' or postscript and will email it to me, I'll see about
converting it to cexec stuff.  I'd prefer a short simple 'C' routine that
does rll decoding, as the ultimate target will be 'C', though if you have
a simple one in postscript, I'll convert to 'C' and then to cexec.  This is
sort of an experiment.  If it works, I'll post the routine to the net.  I'll
also need a short encoded file to test the 'C' code against.

I most certainly will need both ends (compress and uncompress).  Perhaps
if someone has a CCIT group III fax compression and decompression routine
that they can email we can try that also.  That would have some distinct
advantages..


Cheers
Woody

alfred@dutepp1.tudelft.nl (Alfred Kayser) (07/31/90)

woody@chinacat.Unicom.COM (Woody Baker @ Eagle Signal) writes:
>If someone has a nice SHORT compress/decompress
>routine written in 'C' or postscript and will email it to me, I'll see about
>converting it to cexec stuff. 
Me wondering... How portable is cexec code? Can it be used on any PostScript
printer or must it be hand coded for every engine found on the world?
But if it is portable it would be indeed nice to compress image data before
sending it over a slow line.

>Cheers
>Woody
Greeting Alfred.
--
-- Ir. Alfred Kayser. PACS, OS/2, TCP/IP. --- Email: AKayser@et.tudelft.nl --
-- CARDIT, Delft University of Technology ------------ Tel: (31)-15-786179 --
-- P.O.Box 5031, 2600 GA Delft, The Netherlands ------ Fax: (31)-15-784898 --

woody@chinacat.Unicom.COM (Woody Baker @ Eagle Signal) (08/02/90)

In article <.649417057@dutepp1>, alfred@dutepp1.tudelft.nl (Alfred Kayser) writes:
> woody@chinacat.Unicom.COM (Woody Baker @ Eagle Signal) writes:
> >If someone has a nice SHORT compress/decompress
> Me wondering... How portable is cexec code? Can it be used on any PostScript
> printer or must it be hand coded for every engine found on the world?


cexec is more or less specifc.  It exists in all Adobe implementations
for 68000 based laser printers that I am aware of.  There may be some
implementations that don't have it.  If it does not have a 68000 it won't
work.  Perhaps there is the equivalent for other CPU's though I have no
experience with them.  "You pays your money and You takes your chances" 8=}
with other companies' Postscript interpreters.

Cheers
Woody