I on a self-driving car project and i need to detect color white, after doing some research i found that using HSL color model is a pretty good method. Using cv2.inRange with lower_white = [0,100-thrHold,0] and upper_white = [100, 100, 100] i get a result that it show small dot around the image but the one i want to detect which is the small bar within the sign. Im looking for an explanation and better solutions as well.
This is the original : 
And the result : 