Macroblock-based progressive fine granularity scalable video coding

A novel highly efficient macroblock-based progressive fine granularity scalable (MBPFGS) video coding scheme that can optimally balance drifting errors and coding efficiency is proposed in this article. In order to improve coding efficiency, the existing PFGS video coding scheme uses a set of high-quality references to predict the enhancement layers. However, potential drifting errors may arise because high-quality references may not always be available at the decoder when channel bandwidth fluctuates. To solve this problem, we first analyze when drifting errors occur and how they will propagate. Then, an iterative model is established to estimate the drifting errors at the encoder. Meanwhile, three new INTER modes are proposed for the coding of macroblocks at the enhancement layers. One of these modes provides an effective and flexible method to reduce the drifting errors at low enhancement bit rates. Furthermore, we present a decision-making mechanism to select the proper coding mode for each macroblock at the enhancement layers. Experimental results show that the proposed techniques can dramatically reduce drifting errors at low enhancement bit rates, while significantly improving coding efficiency, up to 2.3 dB in average PSNR, compared with MPEG-4 FGS at moderate or high bit rates. (C) 2004 Wiley Periodicals, Inc

Macroblock-based progressive fine granularity scalable video coding

In this paper, we proposed a flexible and efficient architecture for scalable video coding, namely, the macroblock (MB)-based progressive fine granularity scalable video coding with temporal-SNR scalabilities (PFGST in short). The proposed architecture can provide not only much improved coding efficiency but also simultaneous SNR scalability and temporal scalability. Building upon the original frame-based progressive fine granularity scalable (PFGS) coding approach, the MB-based PFGS scheme is first proposed. Three INTER modes and the corresponding mode selection mechanism are presented for coding the SNR enhancement MBs in order to make a good trade-off between low drifting errors and high compression efficiency. Furthermore, temporal scalability is introduced into the MB-based PFGS, which forms the MB-based PFGST scheme. Two coding modes are proposed for coding the temporal enhancement MBs. Since it would not cause any error propagation if using the high quality reference in the temporal enhancement MB coding, the coding efficiency of the PFGST is highly improved by always choosing the most suitable reference for the temporal scalable coding. Experimental results show that the MB-based PFGST video coding scheme can significantly improve the coding efficiency up to 2.8dB compared with the FGST scheme adopted in MPEG-4, while supporting full SNR, full temporal, and hybrid SNR-temporal scalabilities according to the different requirements from the channels, the clients or the servers. 1

Optimal rate allocation for macroblock-based progressive fine granularity scalable video coding

This paper addresses the problem of optimal rate allocation for the macroblock-based Progressive Fine Granularity Scalable (PFGS) video coding. To solve this complicated problem, the error propagation pattern in the macroblock-based PFGS is first investigated. An effective drifting model is established subsequently for estimating the drifting for each enhancement bit stream segment encoded by the macroblock-based PFGS. The distortion reduction for the current frame and the estimated drifting suppression for the subsequent frames form the actual contribution of the enhancement layer bitstream. The equal-slope argument is then applied to select the best bit stream segments for the given bandwidth. Experiments show that our optimal rate allocation outperforms the uniform rate allocation by 0.3-1.4 dB