python中的罗伯茨算子是什么

import cv2 as cv
    import matplotlib.pyplot as plt
    # 读取图像
    img = cv.imread('data.jpg', cv.COLOR_BGR2GRAY)
    rgb_img = cv.cvtColor(img, cv.COLOR_BGR2RGB)
 
    # 灰度化处理图像
    grayImage = cv.cvtColor(img, cv.COLOR_BGR2GRAY)
    # Roberts 算子
    kernelx = np.array([[-1, 0], [0, 1]], dtype=int)
    kernely = np.array([[0, -1], [1, 0]], dtype=int)
    
    x = cv.filter2D(grayImage, cv.CV_16S, kernelx)
    y = cv.filter2D(grayImage, cv.CV_16S, kernely)
    
    # 转 uint8 ,图像融合
    absX = cv.convertScaleAbs(x)
    absY = cv.convertScaleAbs(y)
    Roberts = cv.addWeighted(absX, 0.5, absY, 0.5, 0)
    
    # 显示图形
    titles = ['原始图像', 'Roberts算子']
    images = [rgb_img, Roberts]
    
    for i in range(2):
        plt.subplot(1, 2, i + 1), plt.imshow(images[i], 'gray')
        plt.title(titles[i])
        plt.xticks([]), plt.yticks([])
    plt.show()