[hpoj-devel] more PML gray/color scanning support

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

Hi,

I just checked in some more changes to enable grayscale and color PML
scanning on the OfficeJets.  These new modes save the image as a JPEG
file rather than a PNM file (which turned out to be quite non-trivial!).
I made some other bug fixes and enhancements to "ptal-hp -scan" as well.

So far I have tested this new functionality on an OfficeJet 700, LaserJet
1100A, and LaserJet 3200m.  It should also work on the OfficeJet 600 and
PSC 300 series, and it may or may not work on the OfficeJet 500 and T
series.  I will test with these other models later this week, but of course
I will always happily accept success or failure reports from others.  :-)

There are several issues with ptal-hp documented at
"http://hpoj.sourceforge.net/todo.shtml", including:

- "ptal-hp -scan" doesn't properly set the number of raster lines in a
JPEG image, so your image viewer/editor may report a "corrupt JPEG data"
error.

"ptal-hp -scan" may hang on OfficeJets when scanning in "-bw" or "-bwht"
modes unless you give the "-res 300" switch.

- If you get ptal-mlcd error messages about lookupChannel failures while
scanning with ptal-hp (probably on the OfficeJet 500/600/700/PSC300), try
invoking ptal-mlcd with the "-porttype spp" option.  This may be an ECP
signalling bug, possibly due to waiting to long to go back to forward.

As always, use "cvs update" to pick up the new changes.  Enjoy!  :-)

David