[sane-devel] xsane preview scan?

[Jeff Sadowski]

I'm thinking my best bet is to use the default resolution with max x and max y.


On Thu, Jan 4, 2018 at 10:51 AM, Jeff Sadowski <jeff.sadowski at gmail.com> wrote:
> I have been working on a php implementation of a scanner interface.
>
> I am making some progress. I have my code at
> https://bitbucket.org/jeffsadowski/phpsaneng
>
> (Not anywhere ready for mainstream as for now it just lists the
> options selected when I hit scan.)
>
> I'm at the point where I want to start a preview and I need to make a
> decision of how to get a preview.
>
> I don't see a preview option to scanimage and am curious how xsane
> gets it's preview.
>
> When I try a preview with xsane with test:1 scanner I get a perfect
> grid. (I had set the "Select the test picture" to Grid)
>
> using scanimage '-h' '-d' 'test:1'
>
> I saw the options for test:1
>
> So I tried
>
> scanimage  '--batch=preview.jpg' '--format' 'jpeg' '--batch-count' '1'
> '-d' 'test:1' '--test-picture' 'Grid'
>
> which did not come up with the same grid I get in the preview that xsane shows.
>
> I thought well maybe it is getting the max x and y so I tried
>
> scanimage  '--batch=preview.jpg' '--format' 'jpeg' '--batch-count' '1'
> '-d' 'test:1' '--test-picture' 'Grid' '-x' '200' '-y' '200'
>
> that wasn't it either.
>
> Then I noticed xsane can only set x and y up to 20 which is weird.
> even the defaults are 80 for x and 100 for y
>
> I tried 20x20 and 80x100
> but those didn't result in an image that xsane did either.
> I also tried lowest resolutions that isn't it either. So I am curious
> how xsane acquires a preview?
> Or better yet what is the best way to acquire a preview with scanimage?
>
> I think I would want to have the scanner scan as fast as possible so I
> thought lowest resolution.
> I also think I want my preview of the full bed so max x and max y
> the image I get when I try
>
> scanimage '--batch=preview.jpg' '--format' 'jpeg' '--batch-count' '1'
> '-d' 'test:1' '--resolution' '1' '--test-picture' 'Grid' '-x' '200'
> '-y' '200'
>
> doesn't even look like a grid at all.
>
> So I thought I'd ask this list for some help.