Efficient Bit Allocation Scheme in Low Bit Rate Video Coding

Histogram of differential frame （HOD） was introduced to allocate bits on frame level since it could indicate the motion degree of a picture effectively.Based on HOD pre-analysis,a frame-layer bits allocation scheme is proposed to replace the one used in AVC.In the scheme,a new model of sectional constant frame-layer bits allocation is proposed when motion distribution in a sequence is continuous.Otherwise,a revised linear HOD model is used to allocate bits for a frame if there is abrupt motion change.The final simulation shows that compared to H.264JM76,the proposed bits allocation scheme improves R-D performance by 0.35dB on average and manifests a more smooth subjective quality degradation.