[Foo2zjs-maintainer] Bug#504415: foo2zjs: Ghostscript processing produces blurry printouts

[Luca Capello]

Package: foo2zjs
Version: 20081007dfsg-1~gismo
Severity: normal
Tags: upstream patch
User: irlab at unige.ch
Usertags: print

Hi there!

NB, the version I use is a not-yet-uploaded one as explained at [1].

Since the first time I installed the HP Color LaserJet 1500L the
laboratory where I work has, I was disappointed by the overall bad
quality for printouts when you use the "color" mode.  Since the upstream
page mark it as "alpha quality" I thought it was normal.  However, while
performing some more tests to resolve bug #449497 [3], I found some
interesting stuff.

The bad quality is characterised by two factors: first, color pages are
"darker" than the same ones but printed from Windows XP or Mac OS X 10.4
(thus with the upstream HP driver); second, every shape (being it a text
or a square) has a very dark blue shadow, clearly visible.  While the
former is less important and I guess it could be easily adjusted with an
ICM profile [4], the latter is not acceptable, since it degrades any
printout.

I am now quite sure the blurry problem is caused by Ghostscript during
the image processing, for two reasons:

1) Evince_2.22.2-4 can print without any problem, while lpr produces a
   blurry output when printing the same PDF

2) if the PDF is converted to PS with pdf2ps, even lpr can produces
   correct printouts

Since I am not a Ghostscript expert and I have already spent too much
time with this printer, a quick solution is to generate from the input
data a PS output before converting it to the format the printer expects:

--8<---------------cut here---------------start------------->8---
--- foo2oak-wrapper.in.ORG	2008-11-03 18:35:51.000000000 +0100
+++ foo2oak-wrapper.in	2008-11-03 18:37:18.000000000 +0100
@@ -656,6 +656,7 @@
 
 foo2zjs-pstops $PSTOPS_OPTS | \
 $PREFILTER \
+| ($GS -q -dNOPAUSE -dBATCH -dSAFER -sDEVICE=pswrite -sOutputFile=- -) \
 | ($GS $PAPERSIZE -g$DIM -r$RES $GSDEV $GSOPTS \
     -sOutputFile="|cat 1>&3" $GAMMAFILE -_ >/dev/null 2>/dev/null) 3>&1 \
 | foo2oak -r$RES -g$DIM -p$PAPER -m$MEDIA -n$COPIES -d$DUPLEX -s$SOURCE \
--8<---------------cut here---------------end--------------->8---

IMHO while this works, it is a ugly hack, since the input data is double
processed.

Thx, bye,
Gismo / Luca

Footnotes: 
[1] http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=466758#15
[2] http://foo2oak.rkkda.com/
[3] http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=449497
[4] AFAIK there are no official ICM profiles for this printer

-- System Information:
Debian Release: lenny/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: i386 (i686)

Kernel: Linux 2.6.26-1-686 (SMP w/1 CPU core)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash

Versions of packages foo2zjs depends on:
ii  libc6                         2.7-13     GNU C Library: Shared libraries

Versions of packages foo2zjs recommends:
ii  foomatic-db-engine      3.0.2-20080211-1 OpenPrinting printer support - pro
ii  wget                    1.11.4-2         retrieves files from the web

Versions of packages foo2zjs suggests:
pn  hannah-foo2zjs                <none>     (no description available)
pn  psutils                       <none>     (no description available)

-- no debconf information
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