[sane-devel] Infrared channel

[Gerhard Jaeger]

On Tuesday 22 February 2005 11:54, gerard klaver wrote:
> On Tue, 2005-02-22 at 09:26 +0100, Rene Rebe wrote:
> > Hi,
> > 
> > Gerhard Jaeger wrote:
> > 
> > > the problem is our SANE 1 standard, which defines the image format.
> > > We have currently only the possibility to pass RGB data to a frontend.
> > > 
> > > The solution (whenever we can start) is SANE 2 where we have a more flexible
> > > approach for transmitting image data to a frontend.
> > > It might also be possible for a backend to read the infrared channel and to
> > > perform i.e. the dust removal in the backend, but this functionality should
> > > in general be part of a frontend.
> > > 
> > > VueScans' advantage or disadvantage here is, that you have a all-in-one
> > > program (scanner-driver + image processor), this has never been the
> > > approach of SANE...
> > > 
> > > Maybe it's really time now for SANE 2, but it seems we get more and more
> > > problems in writing new driver code, as reverse engineering consumes too
> > > much time...
> > 
> > I think the immediate available development time is too low for SANE 2 
> > right now. But maybe I'm mistaken ... (I would have the time and 
> > motivation to convert the Avision backend but there are so many others 
> > as well as other applications ...)
> > 
> > However just adding one or more SANE_FRAME_ types would be a trivial task:
> > 
> > SANE_FRAME_RGBI = 5
> > SANE_FRAME_IR = 6
> > 
> > ;-)
> > 
> > But maybe we do not want to do this to have an argument to push SANE 2 ;-)
> > 
> > Yours,
> > 
> 
> Adding some SANE_FRAME_ types which can be used for webcams would also
> be nice (jpg for example).
> Support for icc profiles in the SANE structure would also be nice
> On the Gimp mailinglist they are also busy with discussion about icc
> profiles or better a color management system.

okay, okay, but that is exactly the problem we're running at!
For such changes, we first need the documentation finished and agreed, then
we can do this...

> If SANE 2 means better support possible for the features of scanners,
> webcams there should be made a start someday. 
> Saying this i have no idea how much work it is to convert a SANE 1
> backend to a SANE 2 backend and how much work it is to convert/rewrite
> the frontends also i don't know much about SANE 2 standaard but i expect
> a timetable of 1 or 2 years?

I'm not really sure!
We can reuse a lot of the sanei_ libs, they're tested, maybe some of them
need to be updated. The configure framework can maybe reused...

> The v4l to v4l2 conversion (kernel modules) shows some comparison that
> it takes some time.

Yes, you are right there.
First of all we should agree to what needs to be done, how we are willing
to proceed.
- extending SANE 1
- starting SANE 2, by finishing the documents OR another approach: hacking
  (which is not a good idea)

Ciao,
Gerhard