OpenCV tracking object using a bounding rectangle смотреть онлайн

Using OpenCV and a PS3 Eye camera to track a pink cylinder. Two masks on left are joined to form a single mask. These masks are shown on the top and bottom left. The joined mask is found on the top right. The contour of the mask is found and with it the centroid, area, width, and height of the object in pixels. The centroid is marked in blue,the contour is marked in green, the bounding rectangle is marked in red, and the center of frame is in white. These are shown on the bottom right.

Previously, using the camera calibration function, the camera matrix was found. The cylinder dimensions are already known to be 139.7mm (5.5in) in diameter and 254mm (10in) in height. Using these dimensions and the focal length found in the camera matrix it is possible to approximate the distance to the object. It is also possible to find the angles about the x and y axis of the objects centroid relative to the center of the camera.

These values are shown in the center console output. fps: frames per second, max area: max area in pixels, cx,cy: centroid of the object, pixel width: the width in pixels, pixel height: the height in pixels, thetax: the x or pan angle difference, thetay: the y or tilt angle difference, zw: the distance calculated using the width triangle and the pinhole camera model, zh: the distance calculated using the height triangle and the pinhole camera model, z: the average of the two distances, and zdiff: the difference between the two distances.

The object is moved between about 3353mm (11ft) and 1219mm (4ft). The distance approximation is okay as long as a clear rectangle is viewed but the distance is typically at least 150mm (6in) off. The fps is low because of all the image streaming. With the images off it is around 40fps.