Plustek OpticPro A320E — support for the SANE genesys backend

USB 07b3:1826 · A3 flatbed CCD · GL128

A patch adding support for the Plustek OpticPro A320E, an A3 flatbed CCD scanner for which the manufacturer ships no Linux driver, to backend/genesys/ in sane-backends. Offered to the SANE project as a one-time contribution under GPL-2.0-or-later.

Start with the README. It states the provenance, the licence, how to build it, and the known limitations without varnish.

Updated 2026-09-04. Third version (the 2026-09-04 update corrects the README's description of the tone curve; the code and the patch are unchanged). Since the 2026-08-28 package: the x scale is corrected (0.9991 measured), the whole bed is scannable and the right-hand edge artefacts are gone, the lamp goes out when the carriage starts back, and the motor acceleration is now the vendor's measured table rather than a model. changes.md has the version-by-version account; the README opens with the summary.

One of these changes what you have to do: the white calibration target must now be at least 305 mm wide. This scanner has no internal white strip, so the reference is whatever lies on the glass — and A3 paper is 8 mm too narrow.

README.md Provenance, licence, build and install, reproduction recipes, known limitations
a320e-genesys.patch
.patch.gz
The patch: 17 files, +3394 / −28, against sane-backends master fcaa30a7
changes.md What changed in each published version, what was deliberately not changed, and why
code-quality.md Static analysis: method, results, and the reasoning for every warning left unaddressed
hardware-gl128.md Chip-level findings: ASIC identification, register semantics, the AD9822 front end
hardware-a320e.md Device-specific: model tables, calibration, the resolution model, origin adjustment