The images I'm working with are faxes, so they are typically 1680x2200 pbm (1 bit per pixel) image files.
I wasn't specifying --layout, but adding "--layout single" didn't seem to help. Since my pixels are all black or white, I don't think changing the thresholds would be expcted to make much difference. -- Peter Fales Peter "at" fales-lorenz.net On Fri, Mar 11, 2005 at 04:07:17PM +0100, Jens Gulden wrote: > Hello, > > Peter Fales wrote: > >I get white pages as output on my i686 machine unless I use > >--no-border-scan. I haven't analyzed why - and I'm not sure whether > >running unpaper with all default arguments is even expected to work. > > You're right, the default parameters are NOT expected to always work > out-of-the-box. It depends on the input image whether they make sence or > not. All of my own tests have been made on grayscale paper scans with > "good" contrast, directly originating from scanadf, size 1648 x 2337 pixels. > > Could it be that your scans are too bright, so that the automatic > border-scan treats all pixels as non-black pixels? What happens if you > use different values for --black-threshold or --white-threshold? What if > you set a --border-scan-threshold even lower than the default of 5? > > Are you specifying the --layout parameter, setting it either to 'single' > or 'double'? (Most of the automatic processing makes sence with a > specified --layout only.) > > Please anybody let me know which default values would make more sence > for unpaper. > > Jens > > > -- > sane-devel mailing list: sane-devel@lists.alioth.debian.org > http://lists.alioth.debian.org/mailman/listinfo/sane-devel > Unsubscribe: Send mail with subject "unsubscribe your_password" > to sane-devel-requ...@lists.alioth.debian.org