FindContour

Description

The contour area is calculated as the smallest rectangle that contains the contour.

Mode:

Outermost Contours Only:         retrieves only the extreme outer contours.

All Contours, No Hierarchy:      retrieves all of the contours without establishing any hierarchical relationships.

All Contours, 2 Level Hierarchy: retrieves all of the contours and organizes them into a two-level hierarchy. At the top level, there are external boundaries of the components. At the second level, there are boundaries of the holes. If there is another contour inside a hole of a connected component, it is still put at the top level.

All Contours, Full Hierarchy:    retrieves all of the contours and reconstructs a full hierarchy of nested contours.

Method:

Store All Contour Points:        stores absolutely all the contour points. That is, any 2 subsequent points (x1,y1) and (x2,y2) of the contour will be either horizontal, vertical or diagonal neighbors, that is, max(abs(x1-x2),abs(y2-y1))==1.

Compress Simple Segments:        compresses horizontal, vertical, and diagonal segments and leaves only their end points. For example, an up-right rectangular contour is encoded with 4 points.

Teh-Chin L1 Approximation:       applies one of the flavors of the Teh-Chin chain approximation algorithm.

Teh-Chin KCOS Approximation:     applies one of the flavors of the Teh-Chin chain approximation algorithm.