Performance Analysis of Block-based Permutations in Securing JPEG2000 and SPIHT Compression

摘要

We investigate and compare combined compression-encryption schemes. We assess the respective security, and we show how encryption affects the image coding efficiency. The techniques employ the wavelet-based compression algorithms JPEG2000 and SPIHT, and we randomly permute and rotate blocks of wavelet coefficients in different wavelet-subbands to encrypt image data within the compression pipeline. We identify weak points of the proposed encryption techniques, and possible attacks are highlighted. The investigated methods allow to trade off security for compression performance. The results also have interesting implications with respect to the significance of the zerotree-hypothesis as stated in the context of compression schemes.