Scorpion Update – STC-0032-PolygonCorners

The ability to locate is always important in machine vision. We are at the moment focus on polygon processing.

The new Scorpion Tool Component is  STC-0032-PolygonCorners that locates the corner or turning points of a path or a closed polygon.

Sample 1 – Locating and counting the corners of a rose

The image below shows STC-0032-PolygonCorners processed blob contour of a rose. The STC is set up to locate the concave shape with a minimum curvature. We count 6 rose leaves and the angle for every corner is also estimated.

Locating the corners of a rose

Sample 2 – Locating the loose ends of a broken band

Have you ever tried to locate the loose end of a broken band. With STC-0032-PolygonCorner have we the ability to locate the loose end. We again process the filtered blob contour output and by locating the curvature points of the contour we select the four points that has an corner angle between -60 and -120 degrees.

Locating the loose ends of a broken band by counting the corners

Sample 3 – Locating the straight corners of an rectangle

Another sample is locating and counting the location of the four corners of a rotated rectangle. The point index and the corners angle is shown. The corner angle is slight higher than 90 degrees because the polygon is smoothed and thus the corner is rounded.

Locating the straight corners of a rectangle

Sample 4 – Locating the starting point for the fish-tail

Locating features on living creatures if always a challenge – the main reason is that no fish or creature has the same identical shape. The requires the invention of a more intelligent machine vision.  The image below shows another strategy to locate the starting point of the fish tail using STC-0032-PolygonCorners

The width at the starting point of a fish tail is an important measurement in fish farming and breeding.



The ability to be able to extract curvature points of a polygon is a very valuable feature. It has a large number of usage areas.

The STC-0032-PolygonCorners is available in the  Scorpion Vision Software 9.3 release as an advanced tool extention.