Defines how edges with reversed polarity should be treated.

Values of this enumeration:

• IgnoreGlobally - Matches edges regardless of their polarity; the tool will detect both bright objects on dark background and dark objects on bright background.
• IgnoreLocally - Matches edges regardless of their polarity; the tool will detect even objects that are partially brighter and partially darker than background.
• MatchWeakly - Edge polarity is verified, but reversed polarity does not affect the object score; use it when shadows may cause incidental polarity inversion.
• MatchStrictly - Edge polarity is verified and reversed polarity lowers the object score; use it for fastest matching when object polarity does not change.