Zonal OMR

Reads one or more checkboxes using manually-configured zones.

Remarks

ZonalOMR extracts the state of checkboxes from specified regions (zones) on a document page, using manual configuration for each checkbox location and output value.

Overview

ZonalOMR is designed for structured forms where the position of each checkbox is known in advance. You define each checkbox's location and output value, and the extractor reads their checked/unchecked state from the document image.
This approach is ideal for forms with fixed layouts, such as surveys, ballots, or standardized tests.

Before using ZonalOMR, ensure that the source documents have been processed with Box Detection or Box Removal to identify checkbox regions reliably.

Key Features

• Manual Checkbox Definition:
  Use the 'OMR Boxes' property to define each checkbox's location, output value, and optional registration (alignment) settings.

• Page Filtering:
  The 'Page Filter' property allows you to specify which pages to process (e.g., "1", "1-2", "odd").

• Registration and Alignment:
  The 'Anchor' property provides default registration settings to align checkboxes, compensating for shifts or skew in scanned images.

• Distance Tolerance:
  The 'Maximum Distance' property controls how far a detected box can be from its expected location and still be considered a match.

• Flexible Output Modes:
  Supports Boolean (single checkbox), CheckOne (single selection from multiple boxes), and CheckMulti (multiple selections) modes, as configured in the parent OMR Extractor.

Usage Examples

• Single Checkbox (Boolean):
  Read a single Yes/No or True/False checkbox by defining one OMR Box and using Boolean mode.

• Multiple Choice (CheckOne):
  Define several OMR Boxes for a set of options, and extract the selected value.

• Multi-Select (CheckMulti):
  Extract all checked values from a group of checkboxes, with results separated by the configured delimiter.

Notes

• Always use the same sample document when configuring the 'Anchor' and 'OMR Boxes' properties to ensure alignment.
• The number of OMR Boxes must match the expected output mode (see property remarks).
• For more details, see the documentation for each property and the Zonal OMR wiki page.

Properties

See Also

Anchor DefinitionOMR Box

Used By

Document TypeExtract FromData ColumnData FieldLexicalRules-BasedSpell CorrectorAuto Complete SettingsParagraph MarkerMetadata OptionsOCR LayerLine Periodicity DetectorFixed WidthLabeled ValueSelect PageData TypeOCR ReaderDividerAnchorSimple