LINE SEGMENT AND ARC DETECTION APPARATUS

摘要

An apparatus and method to detect a line segment or arc using Hough transform. A Hough transform unit performs contour extraction on brightness image data to generate contour image data, with pixels having a pixel value of 0 to 255, performs the Hough transform on points in the contour image data, and counts additional values represented by pixel values of points in the contour image data in a Hough table. The Hough transform unit performs contour extraction on first to third component data to generate first to third contour data with pixels having a pixel value of 0 to 255, performs the Hough transform on points in the first to third contour data, and counts additional values represented by pixel values of points in the first to third contour data in the Hough table. The detection unit comprehensively evaluates the counts to detect a line segment or arc.

主权项

1. A detection apparatus for detecting a line segment in a specified image, comprising:
a feature quantity calculating part configured to determine a feature quantity of each point in the specified image; a Hough transform part configured to convert a straight line that passes through an arbitrary point in the specified image to a value set of coordinates (θ,ρ) in a Hough space by representing an arbitrary straight line in the specified image using a length ρ of a perpendicular extending from a reference point of the specified image to the arbitrary straight line in the specified image and an angle θ formed by the perpendicular with a reference axis that passes through the reference point; a counting part configured to add a value weighted by a feature quantity of a point in the specified image in a storage entry corresponding to a value set of coordinates (θ,ρ) in the Hough space to which the point in the specified image is converted by the Hough transform part; and a detection part configured to detect the straight line in the specified image by identifying a value set of coordinates (θ,ρ) for which the count exceeds a first threshold.