Hello everyone, I'm debugging calibration process of hp scanjet 3970. But I'm not familiarized with such process and I'm finding some concepts which are unknown for me.
Looking at google I've found this interesting post containing some useful explanations: http://lists.alioth.debian.org/pipermail/sane-devel/2006-March/016266.html But I have some doubts yet. How concepts like adc-offset and gain values are supposed to affect the final image?. How can they be calculated and applied?. What's the purpose of black and white shading calibration?. Do both processes need to be made? (I see that windows driver enables only black shading calibration in some cases. Why?) Despite the scanner applies by itself such values, what's the formula to apply them in the final image? These are just some questions. Have anyone detailed information about this subject? It could be a good idea to add links about this subject in "Programmer's documentation" section of SANE project to help developers to understand the most common actions that their devices (or official drivers) perform, don't you think? Regards, Jonathan Bravo Lopez
