• Documents were changed when they were  compressed, Xerox found
  • Company posts a blog by its senior engineer  to explain why it happens
  • Xerox criticised for not ordering a recall  when implications could be colossal

By  Helen Collis

PUBLISHED: 12:48 EST, 8  August 2013 |  UPDATED: 04:05 EST, 9 August 2013

 

A researcher in Germany has discovered a  major glitch in Xerox copier machines which have shown to substitute the wrong  numbers when scanning documents.

After scanning a blueprint document from an  architect, David Kriesel, a computer science researcher at the University of  Bonn in Germany, thought the firm was pulling his leg when they accused him of  altering some figures.

But sure enough, on three occasions, the  number six had been replaced with an eight.

Changing numbers: David Kriesel noticed that in some of the numbers he scanned in with a '66' sequence (pictured on the left) they had changed to '86' (pictured on the right) 

Changing numbers: David Kriesel noticed that in some of  the numbers he scanned in with a ’66’ sequence (pictured on the left) they had  changed to ’86’ (pictured on the right)

Technical error: Again, the numbers which feature a 6 on the original document (left) have been changed to an 8 (pictured right). The table shows that 54,60 (left) turns into 54,80 (right) and 65,40 (left) becomes 85,40 (right) 

Technical error: Again, the numbers which feature a 6 on  the original document (left) have been changed to an 8 (pictured right). The  table shows that 54,60 (left) turns into 54,80 (right) and 65,40 (left) becomes  85,40 (right)

Outrage: When Mr Kriesel noticed the error and the company explained, he took to Twitter to spread his alarm 

Outrage: When Mr Kriesel noticed the error and the  company explained, he took to Twitter to spread his concern

He told ABC  News: I thought they were kidding.  But I tried it myself.. and the numbers changed (after being  scanned).’

Alarmed, Mr Kriesel contacted the U.S. firm,  but found no one knew anything about it.

In response,  the company’s principle  engineer posted a five paragraph blog on its website explaining the situation  and how to avoid it.

Frances Tse said the issue had been detected  in certain machines when scan- quality and resolution settings were altered;  when files were compressed, and the quality reduced.

Each page is scanned as a number of small  patches, and the machine replaced each patch with one that best fits from a  library of symbols.

However, when the file quality is reduced,  there is a subsequent ‘tradeoff’ in accuracy, Mr Tse said.

He wrote on his blog: ‘The Xerox design utilizes the recognized industry standard JBIG2 compressor  which creates extremely small file sizes with good image quality, but with  inherent tradeoffs under low resolution and quality settings.’

He explains that for ‘data integrity  purposes’, the company recommends using the factory default settings for  scanning, with quality level set to ‘higher’.

‘In cases where lower quality/higher  compression is desired for smaller file sizes, we provide the following message  to our customers next to the quality settings within the device web user  interface: “The normal quality option produces small file sizes by using  advanced compression techniques. Image quality is generally acceptable, however,  text quality degradation and character substitution errors may occur with some  originals.”,’ he said

Coverage: Mr Krisesl said he thinks the glitch should get some airtime on a late night satirical programme 

Coverage: Mr Krisesl said he thinks the glitch should  get some airtime on a late night satirical programme

Numerous Xerox machines are affected by the glitch, including this ColorQube a 87XX / 89XX model 

Numerous Xerox machines are affected by the glitch,  including this ColorQube a 87XX / 89XX model

 

The potential implications of the Xerox scanning glitch could be very serious, especially if they affect construction documents or medical developments, customers point out 

The potential implications of the Xerox scanning glitch  could be very serious, especially if they affect construction documents or  medical developments, customers point out (stock image of an office)

Mr Tse’s blog, titled ‘Always Listening  To Our Customers: Clarification On Scanning Issue‘  has not been well received however, by  those who fear the potential fallback from this issue could be  colossal.

S. Basinger questioned what will happen when  people find engineering documents are released for construction with numbers  switched by Xerox’s machines, or medical documents have used with switched  figures.

‘A lame response like this suggests that some  of the ignorance of the consequences may be willful and that your senior  leadership is hoping that this will somehow go away,’ the comment continues.

‘Heaven forbid as time continues to tick away  and you delay a proper recall that people die as a result of your  inaction.’

Others criticise the company for failing to  explicitly say which machines are affected, another points out that the warning  message did not show up on his machine when he followed the  instructions.

When one client called the customer services  for advice, he found no one knew what he was talking about.

In response, Mr Tse later added some extra  details in answer to his blog comments.

He pointed out that the product families  affected were numerous: ColorQube 87XX / 89XX, ColorQube 92XX / 93XX, WorkCentre  57XX, WorkCentre 76XX, WorkCentre 58XX, WorkCentre 77XX, WorkCentre 5030/5050,  WorkCentre 6400, WorkCentre 78XX, WorkCentre 51XX, WorkCentre 7220/7225,  WorkCentrePro 2XX / BookMark 40/55, WorkCentre 56XX and WorkCentre  75XX

He also drew attention to the fact that  unless default settings had not been changed, the problem would not  arise.

He said the company was taking the issue very  seriously. He said from people’s feedback ‘we will look for ways to help our  customers better manage their scanning application needs’.

German researcher Mr Krisesl, who has spoken  to both Mr Tse and Xerox’s vice president Rick Dastin, is still concerned about  the consequences.

He told ABC News: ‘This problem is dangerous.  If something is compressed with JBIG2 and I claim it’s incorrect, you can’t  prove me wrong.’

 

Read more: http://www.dailymail.co.uk/news/article-2386900/When-copy-NOT-copy-University-researcher-notices-Xerox-machine-changes-documents-scanning.html#ixzz2bU5YuGle Follow us: @MailOnline on Twitter | DailyMail on Facebook