Shape Classification
Review of shape classification techniques and their limitations.
Tip
Tip
When tuning Canny thresholds, start with threshold1=50 and threshold2=150, then observe the result. Too many edges (including noise)? Raise both thresholds. Too few edges (missing real boundaries)? Lower them. The ratio between threshold2 and threshold1 controls how aggressively weak edges are filtered — keep it between 2:1 and 3:1.
Machine Learning follows a structured pipeline from data to deployment
Common Mistake
Warning
cv2.findContours() modifies the input binary image in older versions of OpenCV. Always pass a copy: cv2.findContours(binary.copy(), ...). In OpenCV 4.x this is no longer an issue, but it is good practice to copy the binary image before passing it to findContours if you need to use it again.