Background-foreground information based bit allocation algorithm for surveillance video on high efficiency video coding (HEVC)

摘要

Bit allocation plays an important role in rate control for it determines the calculation of other parameters of the rate control model. For surveillance videos, however, the bit distribution analysis shows that the foreground parts should get more bits and be encoded in higher quality than background parts. By utilizing the background and foreground information (BFI) provided by surveillance videos, this paper proposes a background-foreground information based bit allocation algorithm (BFIBA). The main idea of BFIBA is to classify a largest coding unit (LCU) into a foreground LCU or a background LCU according to BFI and then allocate bits in both frame level and LCU level and adjust the quantization parameter by using the information provided by the classification. Experimental results show that BFIBA maintains rate control performance, obtaining a rate control error of 0.1% and the foreground coding quality increases by 0.36dB, 0.76dB and 0.82dB in PSNR compared with the three existing bit allocation algorithms in HEVC rate control.