Presets and automatic zone recognition

By default, the Zone Wizard analyzes a document and creates zones that try to match the area or box of a text field and the box for an OMR zone. This means that the zone border is the exact same as the box surround. OMR zones require the entire surrounding box to be contained within the zone because the total number of black pixels present in a zone determines if that OMR zone is marked or unmarked. If part of the box is missing because recognition was off by 1 or 2 pixels, the extraction results may be poor. To account for this, you can add margins to zones so that the zones have some padding around the original detected zone.

Both text zones and OMR zones have a Vertical margin and Horizontal margin option. These margin options enable you to increase the zone size for the detected zones. The size of the OMR zone margins can differ from text zone margins.

If you increment the OMR or text zone margins after zone detection, all zones of that type are increased in real time. If you navigate to another page, the margin settings are retained and displayed immediately if you have already detected zones on that page. Otherwise the margins are displayed when you detect zones on other pages.

For example, if you specify a Horizontal margin of 2 mm and a Vertical margin of 3 mm for text zones, each detected text zone will be 4 mm wider and 6 mm taller than the zone that was originally detected. This extra padding means that if the document shifts within the margin area and registration is unable to account for that shift, extraction may still be successful.

Note Increasing the margins for any zone is a delicate balance. Increasing the margins too much may result in unwanted content included in the zone. Not increasing them enough could truncate content. Either scenario will result in poor recognition. For OMR zones, ensure that the entire box plus a few pixels of white space are contained within the zone for the best results.

Zones must fit within the page, so any margins that fall outside the page boundaries are truncated at the edge of the page.

Margins are not applied to zones until you press Accept Zones. After you close the Zone Wizard, you can then you can edit the properties of each zone individually and configure each zone as needed.