alexpevzner / sane-airscan

Scanner Access Now Easy - universal driver for eSCL (Apple AirScan) and WSD
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Some scanners in the ADF Duplex mode return every second page rotated 180 degrees (usually the back page) #354

Open alexpevzner opened 1 week ago

alexpevzner commented 1 week ago

This is derivative from #339

Some scanners, when scanning in the ADF Duplex mode, return every second page rotated 180 degrees,

For example, Epson Workforce WF-3520 known to have this defect.

This is probably because they implement ADF Duplex by double-scanning the same sheet, and the second (back page) scan, mechanically, appears in the bottom-to-top direction.

Typically, there is no indication of such a rotation, neither in the scanner description, nor in the returned image metadata. So the workaround, if possible, have to be based solely on the device make and model name.

Not sure will I implement workaround or not, but for now I want to keep this issue at least registered/documented.