“When used in lossy mode, JBIG2 compression can potentially alter text in a way that's not discernible as corruption. This is in contrast to some other algorithms, which simply degrade into a blur, making the compression artifacts obvious.[14] Since JBIG2 tries to match up similar-looking symbols, the numbers "6" and "8" may get replaced, for example.
In 2013, various substitutions (including replacing "6" with "8") were reported to happen on many Xerox Workcentre photocopier and printer machines, where numbers printed on scanned (but not OCR-ed) documents could have potentially been altered. This has been demonstrated on construction blueprints and some tables of numbers; the potential impact of such substitution errors in documents such as medical prescriptions was briefly mentioned.”
“When used in lossy mode, JBIG2 compression can potentially alter text in a way that's not discernible as corruption. This is in contrast to some other algorithms, which simply degrade into a blur, making the compression artifacts obvious.[14] Since JBIG2 tries to match up similar-looking symbols, the numbers "6" and "8" may get replaced, for example.
In 2013, various substitutions (including replacing "6" with "8") were reported to happen on many Xerox Workcentre photocopier and printer machines, where numbers printed on scanned (but not OCR-ed) documents could have potentially been altered. This has been demonstrated on construction blueprints and some tables of numbers; the potential impact of such substitution errors in documents such as medical prescriptions was briefly mentioned.”
https://en.m.wikipedia.org/wiki/JBIG2