Re: [hpoj-devel] new hpoj SANE backend in CVS

[David P. <pa...@rc...>]

Joe Piolunek wrote:
> It works here on the OfficeJet 600.  Once everything was set up, it worked 
> surprisingly well.  The only problem I ran into was during an attempt to scan 
> at 150x150 from xsane.  The printer crashed, showing the message "SYSTEM 
> ERROR2252" in the LCD. The crash occurred when the one-page scan was about 
> half finished.
Hi, Joe.  Thanks for your report.  This error number is the same thing
you reported previously with "ptal-hp scan", and unfortunately I don't
know if there's anything I can do about it.  The list of "system error"
codes linked from the "Useful links" page on the hpoj website says that
this number falls in the "image processor error" category.  One suggestion
that just came to mind is to get to the "advanced options" and experiment
with different values for the "JPEG compression factor" option.  It defaults
to 0, which yields the best image quality but least compression.  Perhaps
cranking up that value some will make this problem go away if it's due to
some sort of buffer-overrun bug in the firmware when the compressed data
for a part of the image is bigger than expected.  In order to be scientific
about this test, first find a particular document, scan mode (presumably
color), and resolution where this problem hits fairly reliably.  Then try
increasing the JPEG compression factor gradually, keeping the other
above-mentioned factors constant.  If you can find a threshold value for
this setting that makes this problem go away, then I could very easily
special-case this model to have a different default value for the JPEG
compression factor.  I already had to put a lot of model-specific kludges
into the code; a few more can't hurt.  :-)

David