I.R.I.S. Readiris 14 for Windows User Guide - Manual (Page 82)

Section 8: Editing the Recognition Zones
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Changing the zone type
When scanning bad quality documents, it may occur that Readiris
does not determine the zone types correctly. If that happens, know
that you can change the zone types manually:
 Right-click the zone you want to change.
 Point to Zone > Type, and then click the zone type of your
choice.
Important note: if you are processing bad quality images,
Readiris will likely have problems recognizing them
correctly. Refer to the section Adjusting the Image
Quality to learn how you can avoid such issues.
Changing the zone type of multiple zones simultaneously
When scanning bad quality documents, it may occur that Readiris
does not determine the zone types correctly. If that happens, know
that you can change the zone types manually: