An efficient bit allocation algorithm in dependent coding framework and one-way video applications

We describe an efficient bit allocation algorithm using 2D interpolation of the rate-distortion (R-D) characteristics in a dependent coding environment for applications of one-way video. To solve the dependent coding problem, it is necessary to measure R-D data for all possible combination of quantization settings in the reference frame and the predictive frame. 2D interpolation of rate-distortion characteristics is performed with only a few R-D control points to reduce complexity without significant loss of performance. We also explain a pruning algorithm to further reduce the computational complexity in obtaining R-D characteristics. The cost function for each quantization pair is obtained using 2D R-D characteristics. The complexity is reduced by the 2D-interpolation and pruning algorithm without significant loss of optimality. Experiments with MPEG-2 show that the proposed algorithm provides improvement of PSNR by 0.9∼1.8 dB over the MPEG-2 TM5 algorithm.