http://www.dkriesel.com/en/blog/2013..._when_scanning
Edit: In the last section, it is now sketched that the reason for the issue may be a misconfigured JBIG 2 compression.
In this article I present in which way scanners / copiers of the Xerox WorkCentre Line randomly alter written numbers in pages that are scanned. This is not an OCR problem (as we switched off OCR on purpose), it is a lot worse – patches of the pixel data are randomly replaced in a very subtle and dangerous way: The scanned images look correct at first glance, even though numbers may actually be incorrect. Without a fuss, this may cause scenarios like:
- Incorrect invoices
- Construction plans with incorrect numbers (as will be shown later in the article) even though they look right
- Other incorrect construction plans, for example for bridges (danger of life may be the result!)
- Incorrect metering of medicine, even worse, I think.