实现bmp灰度图像的LSB隐藏，能够将指定的信息嵌入bmp位图的最低位，从而达到数字隐写的目的。另外可以通过相反的过程来读取bmp位图的每一像素的最低位，将信息提取还原出来(BMP gray image LSB hidden, can specify the information embedded in the BMP bitmap of the lowest bit, so as to achieve the purpose of digital steganography. In addition, the lowest position of each pixel of the BMP bitmap can be read by the reverse process, and the information is extracted and restored)