Howtosignalprocessing
- How to detect rectangles in OpenCV Python?
- How could the Hough transformation be used to detect rectangles?
How to detect rectangles in OpenCV Python?
Find the approximate contour for each of the contours. If the number of vertex points in the approximate contour is 4 then we compute the aspect ratio to make a difference between the rectangle and square. If the aspect ratio is between 0.9 and 1.1 we say it is a square else a rectangle See the below pseudocode.
How could the Hough transformation be used to detect rectangles?
Every pixel of the image is scanned, and a sliding window is used to compute the Hough transform of small regions of the image. Peaks of the Hough image (which correspond to line segments) are then extracted, and a rectangle is detected when four extracted peaks satisfy certain geometric conditions.
