简单的 LSB图像水印算法 python版本

LSB Least Significant Bit 最低有效位嵌入，这里就不赘述了。很多参考，原理一搜就出来了。

下面是相应的代码
首先，编写encode 和decode 代码，使用位操作

def LSB_encode(cover, m, k):
    m = np.array(m, dtype = np.uint8)
    cover = np.array(cover, dtype = np.uint8)

    k = 2**k -1
    mask1 = 255-k
    mask2 = k
    cover = np.bitwise_and(cover, mask1)
    m = np.bitwise_and(m, mask2)
    res =  np.bitwise_or(cover,m)
    return res
    
def LSB_decode(cover, k):
    cover = np.array(cover, dtype = np.uint8)
    mask1 = 2**k -1
    
    m = np.bitwise_and(cover, mask1)
    
    res = np.zeros(k, dtype = np.uint8)
    m = str(bin(m))
    m = m[2:].zfill(k)
    for i in range(k):     
        res[i] = int(m[i