[sane-devel] Re Genesys backend and other backends

[Henning Meier-Geinitz]

Hi,
On Thu, Mar 04, 2004 at 04:16:33PM +0530, Sanjay Chigurupati wrote:
> I looked at Henning's page.  I was looking at Genesys backend as reference
> for understanding on how to write backend.

Better use a backend that is already finished. For understanding how a
backend works in principle, you could also look at the "test" backend.
It contains an implementation of (nearly) all features SANE provides.
And you don't need a scanner to try how it works.

> Which of the usb backends on that page would serve as a good example to
> write a backend? I read the status, but I am confused.

I think gt68xx is ok for that. _low.c contains the low level stuff
(calling firmware "functions"). _mid.c is used for converting the scan
data from the scanner's format to something SANE can use. _high.c
conatins all the "intelligent" code that does calibration and actual
scanning. gt68xx.c is the SANE interface.

> I guess I need to set cvs up on my home machine (which has debian woody)
> and get a user login. I will also need ssh client running on my machine,
> right?

If you just want to look at some backend for learning, sane-backends
1.0.13 is ok. Otherwise you can either download a CVS snapshot
(updated daily) or use anonymous CVS. You only need an account (and be
added to the project) if you want to WRITE to our CVS tree.

Bye,
  Henning