[sane-devel] Film scanning and infrared image cleaning

[Julian Hauser]

Hello everyone,

I'm using the Reflecta 10T scanner using the pieusb backend. It mostly works very well, thanks! One thing I have noticed though is that if I enable the infrared scratch and dust removal option "Clean image" in Xsane, the detected defects get painted over with a blurred dot. On film negatives, which have a grainy structure, the results are clearly visible. I've uploaded an example here: https://mis.julianhauser.com/index.php/s/MhSuFltcm0CLIMs. It would be very nice if the corrections repaired the result taking into account the structure of the neighbouring areas (as for example the "healing tool" in GIMP does).

Does the "overpainting" happen in the firmware of the scanner or is that part of sane? If it's part of sane, how is it done? Unfortunately I'm not really a programmer, but I'd very interested in trying to fix this (if it's possible).

Two more things I've noticed with the scanner is that images always come out reversed left-to-right and greyscale scans make xsane crash. These things don't bother me much  as they are easily fixed with a script after scanning. I can send crash logs if someone is interested in debugging this however.

Cheers,
Julian