A scene-adaptive one-pass variable bit rate video coding method for storage media

Abstract

This paper proposes a one-pass VBR (Variable Bit Rate) video coding method that maintains the stability of its quantization scale by using a large size virtual buffer to smooth out the difference between a generated bit count and a target bit count. To improve video quality, the quantization scale is adjusted according to the coding complexity of scenes. Experimental results show that the standard deviations of quantization scale distributions are only 30/spl sim/40% of those produced by CBR (Constant Bit Rate) coding, where averaged quantization scale values are roughly the same as those of CBR. The worst quality periods defined as the duration that the quantization scale exceeds a certain level are reduced from 28.7% to 7.8% in total coding time at 4 Mbps coding. The method can be applied to real-time video recording applications.