Design and implementation of an image based steganography

Along with tremendous increase of software based applications, information privacy has become one of the overborne issues today for efficiency of electronic data processing. The main purpose on privacy of communication is to provide secure connection with target while avoiding to be captured by the third person in a way that flowing data should not be construed. In well accepted sense, steganography is the study and practice of concealing information to provide security of communication. Various LSB methods derived from classic LSB (least significant bit) are used as steganography techniques on spatial domains. In case of direct use of the classic LSB technique, security concern becomes an issue because of its simplicity and predictability. Also, traditional applications of classic LSB inevitably causes distortion of image. In this thesis, carried study proposes an improved LSB Steganography technique to enhance security while decreasing the rate of distortion in subject image. Proposed method in this study is based on hiding two bits of secret data in one color (RGB) pixel with only one least significant bit change in one of the layers. LSB value of Red layer is utilized in XOR operation with both Green and Red LSB values respectively. By applying this technique, only with one LSB bit change, two bits of secret data can be hidden as a consequence of XOR bitwise operation nature. XOR based operation provides more secure and unpredictable communication when compared to classic LSB. Aforementioned methods applied on different images, and it was found that improved method studied here revealed favorable results for the concerns of Peak Signal to Noise Ratio (PSNR) and Mean Square Error (MSE) when compared to the classic LSB method.