A new rate allocation scheme for progressive fine granular scalable coding

We examine the enhancement layer rate allocation problem in progressive fine granular scalable (PFGS) coding. The problem arises from the fact that different frames in the enhancement layer have different rates in PFGS coding. A joint operational rate-distortion (R-D) function for a multi-frame group is first established in enhancement layer PFGS coding, followed by experiments to verify its validity using real test sequences. The optimal rate allocation among frames in the group for the enhancement layer PFGS coding is then given based on the R-D function. Coding results show that, compared to uniform bit allocation, the new bit allocation scheme not only makes the quality variation in decoded video frames smoother, but also improves the coding efficiency of PFGS coding by up to 1.0 dxxB in PSNR. Furthermore, the new scheme has very low complexity, making it suitable for video multicast applications.