Two New Approaches for Secured Image Steganography Using Cryptographic Techniques and Type Conversions

Abstract

The science of securing a data by encryption is Cryptography whereas the method of hiding secret messages in other messages is Steganography, so that the secret's very existence is concealed. The term 'Steganography' describes the method of hiding cognitive content in another medium to avoid detection by the intruders. This paper introduces two new methods wherein cryptography and steganography are combined to encrypt the data as well as to hide the encrypted data in another medium so the fact that a message being sent is concealed. One of the methods shows how to secure the image by converting it into cipher text by S-DES algorithm using a secret key and conceal this text in another image by steganographic method. Another method shows a new way of hiding an image in another image by encrypting the image directly by S-DES algorithm using a key image and the data obtained is concealed in another image. The proposed method prevents the possibilities of steganalysis also. KEYWORDS Steganography, Cryptography, image hiding, least-significant bit (LSB) method