I'm using gscan2pdf 0.9.31 on Crunchbang Linux with my Canon CanoScan N670U. In the scanning window, "Canon CanoScan N670U/N676U/LiDE20" appears on the top. I suppose this is the driver.
Everything works fine as long I scan in 8bit. Scanning in 16bit produces strange visual effects (see http://h9.abload.de/img/scan5blfa.png for a scan of a blank page with 16bit). Moreover, saving doesn't work if the image was scanned in 16bit. I get: "Error creating PDF image object: 16-bits of greylevel in png not supported. at /usr/share/perl5/PDF/API2/Resource/XObject/Image/PNG.pm line 119."
Either, my scanner doesn't support 16bit properly, in which case gscan2pdf shouldn't allow me to chose 16bit (it took me a while to find out why my scans where so grey…). Or, gscan2pdf has a problem with 16bit with that driver.
Please tell me which additional information you need. Thanks in adavance.