python twain
self.SD.SetCapability(twain.CAP_DUPLEXENABLED, twain.TWTY_BOOL, 0) #单面扫描
self.SD.SetCapability(twain.CAP_DUPLEXENABLED, twain.TWTY_BOOL, 1)#双面扫描
self.SD.SetCapability(twain.ICAP_PIXELTYPE, twain.TWTY_UINT16, 0)#012:B/W 灰色 颜色,形成的图片体积越来越大
self.SD.SetCapability(twain.CAP_XFERCOUNT, twain.TWTY_INT16, global_value.distance)#指定扫描数量(与单面扫描配合)