[sane-devel] Snapscan 310 unimplemented features

[Oliver Schwartz]

Hi,

>    I'm using an Agfa SnapScan 310 scanner, its working just fine.
> However, its status shows 'good' rather than 'complete' in the
> support matrix at sane-project site. I would like to know which
> features are still unimplemented (or where to find this information
> if it's available) and if there is any work in progress to
> implement missing functionality, otherwise I'd be very happy to
> contribute.

Well - this question shouldn't be asked by a user - a user should 
simply demand missing functionality :-)

Honestly though, I guess there aren't many features left that can be 
added to the snapscan backend with regard to the SnapScan 310. The 
only thing which comes to my mind is vertical resolution:

The scanner is able to support 300 DPI in horizontal direction, which 
is the optical resolution of the sensor. In vertical direction the 
resolution is determined by the stepper motor. In principle it's 
possible to get higher resolutions here (I'm not sure about the 
SnapScan 310, but I guess something up to 1200 DPI). 

The only difficulty in implementing higher resolutions is that the 
horizontal resolution will always stay at 300 DPI. The backend would 
need some kind of interpolation to also expand the horizontal 
resolution to match the vertical resolution. As far as I know such a 
feature could be used by several backends, so it would be best to 
have something reusable.

The other question is if such a feature does make sense at all, i.e. 
whether you'll acually notice any increased resolution. I rather 
doubt that the resolution of the sensor in it's vertical direction 
really is good enough for 1200 DPI.

>    Not that I'm really an expert in the field of scanners drivers
> development, but I've been coding in c/c++ for some years now, and
> I think I'm able to make my small contribution if welcome.
>
>    Please accept my apologies if this wasn't the right place to
> ask, but I couldn't find a more suitable one,

If you'd like to contribute anything I'd be happy to assist. To be 
honest the resolution problem isn't very high on my priority list. 
Maybe you have also noticed other shortcomings that could be 
enhanced.

Regards,

Oliver