一种基于维吉尼亚密码的图形置乱新算法

imed at the safety problem of digital image transmission, a new image scrambling algorithm based on changing the pixel values was presented in this paper. The algorithm improves the "Vigenere encryption" algorithm, made it suitable in the digital image encryption. Experiment results show that, this algorithm brings the conception of "keyword" which is important in the cryptography in the digital image encryption algorithm. To a certain degree, it enhanced the security of scrambling image, compared with the algorithm which is based on changing the pixels position. This method not only provides with a better scrambling effect, but also changes the gray histogram of scrambling image obviously. Besides, this method has a better ability of resist noise compared with the "Bit-exclusive-or" algorithm -the traditional image scrambling algorithm based on changing the single pixel values.