In this paper, we propose a layered multicast encryption scheme that provides flexible access control to motion JPEG2000 code streams. JPEG2000 generates layered code streams and offers flexible scalability in characteristics such as resolution and SNR. The layered multicast encryption proposal allows a sender to multicast the encrypted JPEG2000 code streams such that only designated groups of users can decrypt the layered code streams. While keeping the layering functionality, the proposed method offers useful properties such as 1) video quality control using only one private key, 2) guaranteed security, and 3) low computational complexity comparable to conventional non-layered encryption. Simulation results show the usefulness of the proposed method.

This paper proposes two efficient rate control algorithms for Motion JPEG2000. Both methods provide accurate visual quality control under buffer constraints. Frames of the same scene usually have the similar rate-distortion (R-D) characters. The proposed methods predict the R-D models of uncoded frames forwardly or bilaterally according to those of coded frames. Experimental results demonstrate that the proposed algorithms offer visual quality improvements over similar competing methods and save a large amount of memory simultaneously.

The paper proposes a constant bit rate (CBR) control algorithm for motion JPEG2000 (MJ2). In MJ2 coding, every frame can be coded at similar target bitrate due to the accurate rate control feature. Moreover, frames of the same scene have the similar rate-distortion (RD) characters. The proposed method estimates the initial cutoff threshold of the current frame according to the previous frame's RD information. This iterative method reduces computational cost significantly. As opposed to previous algorithms, it can be used at any compression ratio. Experiments show that the performance is comparable to normal JPEG2000 coding.

In this paper, we propose a novel QoS (Quality of Service) estimation scheme for JPEG 2000 coded image at RTP (realtime transfer protocol) layer without decoding the image. QoS of streaming video is estimated in view of several points, such as, transmission delay, or quality of received images. In this paper, we evaluate the QoS in terms of quality of received images. Generally, RTP is carried on top of UDP, and hence, quality of transmitted images could be degraded due to packet loss. To estimate the quality of received JPEG 2000 coded image without decoding, we use RTP header extension in order to send additional information to the receiver. The effectiveness of the proposed method is confirmed by the computer simulations.