给图像添加椒盐噪声

椒盐噪声也称为脉冲噪声，是图像中经常见到的一种噪声

def salt_and_pepper_noise():
    '''
    添加椒盐噪声
    image:原始图片
    prob:噪声比例
    '''
    prob = 0.1
    import cv2
    import random

    image = cv2.imread('sample1.jpg')
    output = np.zeros(image.shape,np.uint8)
    noise_out = np.zeros(image.shape,np.uint8)
    thres = 1 - prob
    for i in range(image.shape[0]):
        for j in range(image.shape[1]):
            rdn = random.random()#随机生成0-1之间的数字
            if rdn < prob:#如果生成的随机数小于噪声比例则将该像素点添加黑点，即椒噪声
                output[i][j] = 0
                noise_out[i][j] = 0
            elif rdn > thres:#如果生成的随机数大于（1-噪声比例）则将该像素点添加白点，即盐噪声
                output[i][j] = 255
                noise_out[i][j] = 255
            else:
                output[i][j] = image[i][j]#其他情况像素点不变
                noise_out[i][j] = 100
    cv2.imshow('random_noise', noise_out+output)
    cv2.waitKey(0)