[sane-devel] sane 1.0.31 backend version not supported lineart. Why?...

[m. allan noah]

On Thu, Sep 24, 2020 at 6:04 AM Wolfram Sang <wsa at kernel.org> wrote:
>
> On Thu, Sep 24, 2020 at 11:59:39AM +0200, Ulf Zibis wrote:
> >
> > Am 24.09.20 um 11:45 schrieb Wolfram Sang:
> > >
> > > !458 explains some more: "The LINEART support within the backend is
> > > implemented as a pure software filter. I think this should live in a
> > > higher level and be reusable by all backends instead of being duplicated
> > > within each backend."
> >
> > I agree, that having a gray->lineart filter in each backend is nonsense, but is there a possibility for such a filter in a intermediate layer?
>
> Well, I assumed the answer is 'no'. If it was 'yes', then the proper
> path would be to first code it, convert the users, and only finally
> delete the now obsolete stuff, no?
>

Agreed. Removing code that your users have come to rely on, without
providing a replacement is bad form. In this case, this is a sort of
expected feature for most scanners. I think it should not be provided
by another layer, instead it could be a shared library that all
backends can use. I wrote sanei_magic to provide software deskew and
cropping algorithms to all backends, for just this reason. I've got a
pretty good lineart function in the epjitsu backend, that I could move
up to sanei_magic if other backends wanted to use it.

allan
-- 
"well, I stand up next to a mountain- and I chop it down with the edge
of my hand"