Secure, media streaming & secure adaptation for non-scalable video

Two important capabilities in media streaming are (1) adapting the media for the time-varying available network bandwidth and diverse client capabilities. and (2) protecting the Security of the media. Providing both end-to-end security and adapting at a (potentially untrusted) sender or mid-network node or proxy can be solved via a framework called Secure Scalable Streaming (SSS) which provides the ability to transcode the content without requiring decryption. In addition. this enables Secure transcoding to be performed in a R-D optimized manner. The original SSS work was performed for scalably coded media. This paper examines its potential application to non-scalable media. Specifically, we examine the problems of how to scale non-scalable H.264/MPEG-4 AVC video and how to do it Securely. We first show, perhaps surprisingly, that the importance of different P-frames in a sequence can vary by two orders of magnitude. Then we propose two approaches for securely streaming and adapting encrypted H.264 video streams in an R-D optimized manner Using (1) Secure-Media R-D Hint Tracks. and 2) Secure Scalable Packets. While we can not scale the bit rate of encrypted non-scalable H.264 to the same extent possible for scalably coded media, our method does provide some scaling capability and more importantly provides 4-8 dB gain compared to conventional approaches.