Principle, Benefits and Applications of Variable Bit Rate Coding for Digital Video Broadcasting

This paper studies the principle and benefits of variable bit rate coding of MPEG-2 video compression. The study starts from the fundamental difference of rate control algorithms for constant bit rate (CBR) coding and variable bit rate (VBR) coding. Comparison test results from the real-time video encoder and decoder operation using a PAQ200 picture quality analyzer as the tool for coded video quality measurement are reported and analyzed in association with the rate control algorithms. The combined theoretical analysis and experimental results show that the VBR coding has a significant bit saving potential over the CBR coding for the same coding quality. To effectively utilize the gain from the VBR coding, three bit stream transport mechanisms are introduced. Finally some potential applications that can benefit from the VBR coding have been identified.

Published

1999-02

Content type

Original Research

DOI

10.5594/M00951

ISBN

978-1-61482-930-0