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Flameeyes / scan2pdf

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How to darken image? #3

Open chuckb opened 12 years ago

chuckb commented 12 years ago

Using an HPLJ3055 multi-function unit. Pencil drawings in lineart mode are not legible. In grey scale mode, more comes out but still not legible. Is there a way to adjust the interpretation between light and dark?

chuckb commented 12 years ago

After looking at the unpaper utility, it appears like --black-threshold may be the switch to tinker with.

Flameeyes commented 12 years ago

scanimage, for some models has a way to regulate the brightness sensitivity, but since I never had to deal with a very variable scanner I didn't implement a wrapper around it.

I might just end up with -Wa -Wu and so on options alike to how the compiler frontend allows passing parameters to its backends, with a huge warning when using something that is not interpreted...

chuckb commented 12 years ago

Yes, I dug at some length in the backend code for hplib and it appears like it is unsupported. But it may be possible with unpaper (with lesser degree of success I realize). Will tinker with and report back, with code within scan2pdf to send to unpaper.

Flameeyes commented 12 years ago

I think the solution would be to have a configuration file to set per-device default options (for instance for mine it would be -A -c since it's an adf-only, center-based scanner), adding to the -Wu, -Ws, -Wt, options that I noted in the other issue (cc style).