[sane-devel] fujitsu deskew background artifacts

[Olaf Meeuwissen]

Hi Paul,

G. Paul Ziemba writes:

> There seems to be something wrong with the software deskew operation
> in SANE. I'm hoping someone can either confirm it is a bug or suggest
> alternate arguments to scanimage to fix the problem. I am also happy
> to modify C code and try patches.

I'm no expert here but looking at your images and the fujitsu backend
code,

 - what does a swcrop'd only image look like?
 - what if you add a call to buffer_crop before buffer_deskew in the
   backend/fujitsu.c code?

The code currently has

    /* finished buffering, adjust image as required */
    if(s->swdeskew && (!s->hwdeskewcrop || s->req_driv_crop)){
      buffer_deskew(s,s->side);
    }
    if(s->swcrop && (!s->hwdeskewcrop || s->req_driv_crop)){
      buffer_crop(s,s->side);
    }

The idea is to run crop, deskew, crop, so change that to

    /* finished buffering, adjust image as required */
    if((s->swdeskew && s->swcrop) && (!s->hwdeskewcrop || s->req_driv_crop)){
      buffer_crop(s,s->side);
    }
    if(s->swdeskew && (!s->hwdeskewcrop || s->req_driv_crop)){
      buffer_deskew(s,s->side);
    }
    if(s->swcrop && (!s->hwdeskewcrop || s->req_driv_crop)){
      buffer_crop(s,s->side);
    }

> Many thanks for your anticipated suggestions.

Hope this helps,
-- 
Olaf Meeuwissen, LPIC-2            FSF Associate Member since 2004-01-27
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