Run length based connected components and contour following for enhancing the performance of circled region extraction algorithm

摘要

A method for identifying contours in image data includes expressing pixel-based image data as a grid of columns and rows. A scan order is established over the grid to define a parent-child relationship between contiguous pixels in adjacent rows and to define a sibling relationship among non-contiguous pixels in the same row. A run data structure is established in computer-readable memory that defines a run member by its row position and by its starting and ending column positions. The run data structure further defines parent, child and sibling structures for storing information about the parent-child relationships and sibling relationships of pixels associated with the run member. The run data structure is used to traverse the parent, child and sibling relationships and thereby identify contours within the pixel-based image data.