[sane-devel] Avision scanimage & image quality

[René Rebe]

On Wednesday 25 July 2007 15:10:08 Richard Reina wrote:
> Rene,
>  
>  Since dropping the "mode --Dithered" from my scanimage command the quality has improved somewhat.  However, when I print the document it does not look anywhere near as good as it did when viewed with $:display document.tiff.  Will optimize2bw help this?  Or do I have a printing quality issue?
> 
>  Thanks for the help thus far.

As with all technical systems the devil is in the details. And espeially with all
the different color scanning and also printing techniques - including different
materials.

The questions is what kind of techniques your printer does utilize, which
printer is it by the way?

If the document looks good no the screen and totally different when printed
out then you more likely have some problem in your print queue.

However with many print spoolers and rasterizers (including printer
firmware rasterizers) it also depends how the PostScript/PDf is generated
as there several different methods to embed image raster data in those
files and most spoolers and firmware handle them differently.

If you expect this  free and open source scanner related list to help you
out you certainly need to drop some more details what printer you use
and what you try to archive.

Optimize2bw is an automatic thresholding application doing some
sharpening and background color removal on the image and trying
to preserve as much detail as possible to create 1bit b/w image for
archival.

Yours,

> René Rebe <rene at exactcode.de> wrote: On Tuesday 24 July 2007 18:29:12 Richard Reina wrote:
> > I have an Avision AV210 that I use to scan in documents with the scanimage command:
> > 
> > scanimage --mode Dithered --resolution 200 --format tiff > file_name
> > 
> > Can anyone recommend syntax to darken the document it and make it more clear?
> 
> All color tuning, including brightness, contrast and gamma also work in the
> Dithered mode (in the Avision backend). Btw. Why do you use dithered at all?
> 
> If you want automatic thresholding you can scan in Gray (or Color) and use
> optimize2bw from ExactImage:
> 
>   http://www.exactcode.de/site/open_source/exactimage/econvert/
>   http://www.exactcode.de/site/open_source/exactimage/utilities/
> 
> Yours,
> 
> -- 
>   René Rebe - ExactCODE GmbH - Europe, Germany, Berlin
>   Geschäftsführer: Susanne Klaus, René Rebe
>   Sitz: Berlin, Amtsgericht Charlottenburg HRB 105 123 B
>   USt-IdNr.: DE251602478
>   http://exactcode.de | http://t2-project.org | http://rene.rebe.name
> 



-- 
  René Rebe - ExactCODE GmbH - Europe, Germany, Berlin
  Geschäftsführer: Susanne Klaus, René Rebe
  Sitz: Berlin, Amtsgericht Charlottenburg HRB 105 123 B
  USt-IdNr.: DE251602478
  http://exactcode.de | http://t2-project.org | http://rene.rebe.name