Desktop CDs: Around 60 MB saved on the installed system, 28 MB in binary packages

[Till Kamppeter]

Hi,

the Google Summer of Code 2010 is over and the only student working for 
OpenPrinting, Vitor Baptista from Brazil, was successful with the 
project of effectively compressing PPDs for PostScript printers which 
are physically residing on the system. I have made use of this software 
now in the foomatic-db and hplip packages leading to the following savings:

Binary Package             *.deb file       installed system
------------------------------------------------------------
openprinting-ppds               ~4 MB                  ~5 MB
openprinting-ppds-extra        ~18 MB                 ~28 MB
hplip-data                      ~4 MB                 ~26 MB

So on the running system of the Desktop CD 31 MB get saved which can be 
used for other useful things.

All these savings are solely reached by lossless data compression. No 
functionality is removed from the PPDs, not even comments. Especially 
the multi-language support of HP's PPDs is conserved.

Note also that the splitting of openprinting-ppds and 
openprinting-ppds-extra was done to remove a big part of the 
space-consuming PPD files from the Desktop CD. Now as the data is vastly 
compressed I am thinking about merging the PPDs of 
openprinting-ppds-extra back into openprinting-ppds and doing away with 
openprinting-ppds-extra. WDYT?

See also

http://pypi.python.org/pypi/pyppd
https://bugs.launchpad.net/bugs/493282
   hplip-data ballooned by 2.5 MB in lucid
https://bugs.launchpad.net/bugs/446245
   lzma more efficient than gzip

Thank you, Vitor, for your great work!

    Till