Steganography aims to hide a message (called stego text) imperceptibly in an input image (known as cover image) resulting in an output stego image (without visible distortion) so that the existence of the message isn't suspected. It provides security through obscurity and is used to convey messages secretly between a sender and a recipient. Steganography hides the message so that it is hard to be observed, unlike cryptography, which encrypts the message so that it is (computationally) hard to be decrypted or understood. On the contrary, steganalysis refers to the process of detecting secret messages that were hidden using steganography; cryptanalysis has a similar relationship with cryptography.
In this recipe, we shall demonstrate a very popular steganography technique known as LSB data hiding (secret messages can be hidden by storing...