Abstract OPTIMAL VIDEO SUMMARIZATION FOR MULTIPLE PATH COMMUNICATION

For video communication over wireless ad hoc networks, multiple paths with different rates are common. This thesis considers the transmission of different summaries of an intra– coded video sequence through k bandwidth limited paths. The reconstruction of the joint summary of all k paths results in the smallest maximum distortion that can be achieved. We propose a framework which can solve this problem in an iteration with two steps. First, a rate-distortion optimal summary for a logical channel is generated. The size of the logical channel is the sum of all available channels. In a second step, this summary is tried to split into the k paths. If this is not possible a new summary for a logical channel with lower size is generated until a solution is found that can be split. For k> 2 splitting algorithms have been examined but not implemented. For k = 2 a greedy suboptimal distribution algorithm and an optimal distribution algorithm, based on the knapsack theory, are shown. Results of extensive experimental test comparing the performance of the two splitting algorithms are presented. Acknowledgement Our first and most important acknowledge goes to our Professor Guido M. Schuster. Wit

ICIP’05 draft, v2.0-1- revised: 9/14/2005 VIDEO SUMMARIZATION FOR MULTIPLE PATH COMMUNICATION

For video communications over wireless ad hoc networks, multiple paths with limited bandwidth are common. It therefore presents new challenges to the video encoding. In this paper, we formulate the problem as a multiple path video summarization problem under bit rate constraints, where video summaries are generated to satisfy each channel’s rate constraint, while the combined summary at the receiving end achieves the minimum summarization distortion. The optimal solution (within a convex hull approximation) is found by Lagrangian relaxation and dynamic programming. Simulation results demonstrate the effectiveness of the approach. 1