[sane-devel] [sane-pixma] Canon MF4150 v. PIXMA_CAP_LINEART

[Samuel Adam]

I know experientially that the Canon imageCLASS MF4150 is possessed of 
a 1-bpp lineart mode.  Pages fly through the automatic feeder, and text 
is accorded an OCR-friendly crispiness lacking in the greyscale mode.  
The Canon-provided Windows-only software provides two modes it 
respectively terms "Black and White" (not too good) and "Black and White 
Text" (much better).[1]  I do not currently have a Windows machine 
available, and I need to make some scans *yesterday*.

sane-pixma permits only --mode Color or --mode Gray with the MF4150, 
and `scanimage -A` shows only these options.

What would happen if I simply ORed in PIXMA_CAP_LINEART at the 
appropriate line in pixma_imageclass.c?

-   DEV ("Canon imageCLASS MF4150", "MF4100", MF4100_PID, 600, 640, 
877, PIXMA_CAP_ADF),
+   DEV ("Canon imageCLASS MF4150", "MF4100", MF4100_PID, 600, 640, 
877, PIXMA_CAP_ADF | PIXMA_CAP_LINEART),

I expect this would lead to Bad Things, what with all the moving parts 
I skimmed past.  But is any other way to make it work right quickly?

Sorry to return ENOTIME on the project to actually familiarize myself 
with sane-pixma code, beyond a simple grep.  And thanks to the folks who 
reverse-engineered the Canon protocols, so I can use scanner at all.

Samuel Adam


[1] The idiot-friendly software has a checkbox captioned "Show Scanner 
Driver".  Check it, and options galore do arise.