Perceptual cryptography on JPEG2000 compressed images or videos

In this paper, a perceptual cryptography combining with JPEG2000 codec is proposed, which permutes different number of bit-planes in each coefficients' block, encrypts different number of coefficients' signs, and permutes code blocks in different ftequency bands. Thus, the images or videos can degraded to different degrees under the control of quality factor. Theoretical analyses and experimental results show that, its encryption strength can be adjusted according to certain quality factor, it is of low-cost, it supports direct bit-rate control, and it is not sensitive to transmission errors. These properties make it more suitable for network multimedia applications with real-time operation requirement, such as Video-on-Demand (VOD) system, multimedia communication, wireless or mobile multimedia, and so on.