morphology_utils.py 文件源码

def threshold_value(img):
    """
    Returns a threshold value (0.9 or 0.98) based on whether any slice
    of the image within a central box is enterely white (white is a bitch!)
    0.9 or 0.98 come simply from a lot of experimentation.
    """

    is_color = len(img.shape) == 3
    is_grey  = len(img.shape) == 2

    if is_color:
        gray =  cv2.cvtColor(gray,cv2.COLOR_BGR2GRAY)
    elif is_grey:
        gray = img.copy()

    slices = gray.mean(axis = 1)[20:gray.shape[0]-30]
    is_white = any(x > 0.9*255 for x in slices)
    if is_white:
        return 0.98
    else:
        return 0.9