A secure 3D-SPIHT codec

Due to the properties of large-volume and real-time requirement, video is difficult to be encrypted directly by traditional cryptography. Video encryption algorithms taking compression process into account are preferred. In this paper, an encryption scheme combining with 3D-SPIHT encoding is proposed, in which, wavelet coefficients in each data cube are confused based on octree confusion and their signs are encrypted by a chaotic stream cipher. What´s more the relative positions of data cubes are confused. The encryption scheme changes the compression ratio slightly, is of low-cost and supports direct bit-rate control. These advantages make it suitable for multimedia applications with real-time operation requirement such as multimedia network, wireless multimedia, mobile multimedia and so on.