Xerox has fessed up to a bug on its scanners which mean that some of its photocopiers have been reading numbers and replacing them with others.
Xerox says it will release a software patch for its Workcentre devices can result in numbers and letters being changed in saved files. Apparently the problem is caused if users fiddle with their machine’s default settings to lower its resolution in order to save documents at smaller file sizes.
However, it acknowledges that referring to the affected mode as "normal" on the devices' selection screens needs to be reconsidered. The problem is the result of a compression technique widely used in the industry and it will not harm the majority of users’ machines.
David Kriesel, a German computer scientist, noticed that two Xerox Workcentre models he used had randomly altered numbers in pages they had scanned. Switching the scanning mode from the default "higher" quality setting to "normal" quality resulted in the machines adopting the Jbig2 compression standard, he said.