A Rate Control Method for Reducing Quality Fluctuation in the 3D Embedded Wavelet Video Coder

Current rate control schemes in MCTF-based wavelet video coding lack efficient GOP-level bit allocation due to the shortage of GOP rate-distortion (R-D) information and the limitations of real-time encoding. Exploiting the advantage of offline video encoding, a GOP-level bit allocation scheme based on GOP R-D data estimated from the wavelet decomposed temporal-spatial subband R-D is described. Each video sequence is encoded twice. In the first pass, the R-D information of the GOP is generated, and this is utilised in the second pass to implement GOP-level bit allocation appropriate for the available bandwidth and such that the video sequence is coded with near-constant quality. Experimental results demonstrate that the proposed technique achieves a smoother, and hence more visually acceptable, quality than existing methods.