clahe opencv
bgr = cv2.imread(image_path)
lab = cv2.cvtColor(bgr, cv2.COLOR_BGR2LAB)
lab_planes = cv2.split(lab)
gridsize=8
clahe = cv2.createCLAHE(clipLimit=2.0,tileGridSize=(gridsize,gridsize))
lab_planes[0] = clahe.apply(lab_planes[0])
lab = cv2.merge(lab_planes)
bgr = cv2.cvtColor(lab, cv2.COLOR_LAB2BGR)