Abstract
Steganography and cryptography are techniques that try to protect message from being captured during data transmission. Algorithms which combined steganography and cryptography can provide a higher security. In this thesis, we propose a least significant bit (LSB) based steganography. In order to enhance the security, we use linear feedback shift register (LFSR) to generate random sequences to do exclusive-or (XOR) operations with the secret message and then embed the ciphered message into biometric images. In the capacity aspect, our algorithm can support up to four least significant bits (4LSB) replacement according to the size of message. The effectiveness of the proposed method is estimated by peak signal-to-noise ratio (PSNR), embedding rate and execution time. The results show that high PSNR values with short execution time is feasible.