[sane-devel] Could XSane process the threshold while lineArt scan?

[m. allan noah]

On 6/23/08, eagleskycloud <eagleskycloud at gmail.com> wrote:
> My driver process the threshold  at present .  If  the value of  pixel
> greater than the threshold ,the value of pixel is set 255. Otherwise the
> value of pixel is set 0.

well, that is not very much code, so i would leave it in your backend.
if someone ever writes a good adaptive algorithm and your source code
is free, it can be updated. I plan to do the same with my backends.

allan

>
> 2008/6/23 m. allan noah <kitno455 at gmail.com>:
>
>
> >
> >
> >
> > On 6/23/08, Daniel Glöckner <daniel-gl at gmx.net> wrote:
> > > On Mon, Jun 23, 2008 at 05:04:57PM +0800, eagleskycloud wrote:
> > >  >      My driver process threshold while lineArt scan now. If XSane
> could
> > >  > process threshold, my driver would get simple.
> > >
> > >
> > > IMHO lineArt should be advertised only for devices that can do the
> > >  conversion in hardware. Doing it in hardware has the benefit of reduced
> > >  USB/SCSI bandwidth. Drivers should not cover up for cheap hardware.
> > >
> > >  There is a list of planned features for XSane.
> > >
> > >  http://www.xsane.org/xsane-future.html
> > >
> > >  If you want lineArt conversion to be included there, you need to
> contact
> > >  the author. He is no longer on this mailing list.
> >
> > this is a place where i disagree with daniel, for two reasons-
> >
> > 1. It would still help with bandwidth in the net backend case, which
> > sould like it might become the standard in some future version of
> > sane.
> >
> > 2. it is good if all backends present a similar interface, so that
> > front-ends like scanimage can still have access to these functions.
> >
> >  to that end- i have been working on a sanei_threshold library that
> > backends of dumb scanners could share. it still has the same effect of
> > code only in one place. i need a good algorithm though- eagleskycloud-
> > what mechanism were you planning to use? straight threshold, or
> > something adaptive?
> >
> > allan
> > --
> > "The truth is an offense, but not a sin"
> >
>
>


-- 
"The truth is an offense, but not a sin"