One of the main techniques in steganography is hiding messages in images by altering the least significant bits (LSB) of the pixels with those of the message bits. The result is an image with a message hidden in it that the human eye cannot distinguish from the original image. This is because, on changing the LSB in the pixels of an image, the pixel values are only altered by a small amount, resulting in a visually similar image.
There are two prominent methods for LSB:
- The naïve method is called LSB replacement. In this method, the LSB bit remains unchanged if the message bit is the same as the LSB; otherwise, the bit is altered. Hence, the odd pixels are reduced by 1 in intensity, whereas the even pixel values are incremented by 1. However, this causes an imbalance in the image histogram, which can be easily detected by statistical methods for steganalysis...