Independent Protection of Different Layers in Spatially Scalable Video Coding

In this paper, a novel method for independent access of different layers of protected scalable video coding (SVC), based on framework of state of the art H.264/AVC, is presented. For a SVC bitstream, a user accessing the base layer needS only one key while users accessing the enhancement layer need keys for both the base layer and enhancement layer. Hence if a user is accessing the highest available layer, keys of all the lower layers are also needed to decode it properly. We have devised a scheme in which the user accessing any particular resolution use only one key whether it is the base layer or any of the enhancement layers, and all the keys have the same length. Advanced encryption standard (AES) algorithm in Cipher Feedback (CFB) mode has been used in this scheme to make the keys secure. The scheme has been tested both for offline playback and online streaming environment. Five different benchmark video sequences having three resolutions and containing different combinations of motion, texture and objects are used for experimental evaluation of the proposed algorithm.