计算机应用研究
計算機應用研究
계산궤응용연구
APPLICATION RESEARCH OF COMPUTERS
2010年
2期
439-442
,共4页
任胜兵%江伟%陈元%黄自武
任勝兵%江偉%陳元%黃自武
임성병%강위%진원%황자무
二进制算术编码器%重归一化%按位操作%区间划分
二進製算術編碼器%重歸一化%按位操作%區間劃分
이진제산술편마기%중귀일화%안위조작%구간화분
binary arithmetic coder (BAC)%renormalization%bitwise-operation%interval division
重归一化是H.264/AVC标准二进制算术编码器的一个关键部分,在算术编码器中,重归一化计算量很大,严重制约了算术编码器的效率;同时重归一化算法是一个按位操作过程,很多情况下通过运行一次重归一化算法并不能完成重归一化操作,因此消耗了大量编码时间.为了减少编码时间,针对影响重归一化速度的瓶颈问题,提出了一种基于区间划分的快速重归一化算法.根据重归一化循环次数提出六种不同的区间划分标准来去除H.264/AVC重归一化算法中消耗大量编码时间的按位操作过程;通过去除重归一化的循环过程,使得算法在单位时间内向编码流中输出更多的比特数,能够更好地满足实时性的要求.实验表明,快速重归一化算法在原重归一化算法基础上减少了21.9%~26.7%的重归一化次数和14.5%~33.7%的编码时间.
重歸一化是H.264/AVC標準二進製算術編碼器的一箇關鍵部分,在算術編碼器中,重歸一化計算量很大,嚴重製約瞭算術編碼器的效率;同時重歸一化算法是一箇按位操作過程,很多情況下通過運行一次重歸一化算法併不能完成重歸一化操作,因此消耗瞭大量編碼時間.為瞭減少編碼時間,針對影響重歸一化速度的瓶頸問題,提齣瞭一種基于區間劃分的快速重歸一化算法.根據重歸一化循環次數提齣六種不同的區間劃分標準來去除H.264/AVC重歸一化算法中消耗大量編碼時間的按位操作過程;通過去除重歸一化的循環過程,使得算法在單位時間內嚮編碼流中輸齣更多的比特數,能夠更好地滿足實時性的要求.實驗錶明,快速重歸一化算法在原重歸一化算法基礎上減少瞭21.9%~26.7%的重歸一化次數和14.5%~33.7%的編碼時間.
중귀일화시H.264/AVC표준이진제산술편마기적일개관건부분,재산술편마기중,중귀일화계산량흔대,엄중제약료산술편마기적효솔;동시중귀일화산법시일개안위조작과정,흔다정황하통과운행일차중귀일화산법병불능완성중귀일화조작,인차소모료대량편마시간.위료감소편마시간,침대영향중귀일화속도적병경문제,제출료일충기우구간화분적쾌속중귀일화산법.근거중귀일화순배차수제출륙충불동적구간화분표준래거제H.264/AVC중귀일화산법중소모대량편마시간적안위조작과정;통과거제중귀일화적순배과정,사득산법재단위시간내향편마류중수출경다적비특수,능구경호지만족실시성적요구.실험표명,쾌속중귀일화산법재원중귀일화산법기출상감소료21.9%~26.7%적중귀일화차수화14.5%~33.7%적편마시간.
Renormalization is a key part of BAC in H.264/AVC standard.In BAC,the renormalization has seriously constrained the efficiency of the arithmetic coding because its computational complexity is high.Renormalization algorithm is a bitwise-operation procedure.In many cases,the renormalization operation can't be finished by running renormalization algorithm for one time,so it is consuming a lot of coding time.In order to reduce the coding time,this paper introduced a fast renormalization algorithm based on interval division to deal with the bottleneck problem in renormalization.According to the number of cycles in renormalization loop,this fast renormalization algorithm introduced six different interval division standards to replace time-consuming,bitwise-operation procedure.At the same time,through removing the cycle of renormalization procedure,the algorithm could output more bits to coding stream in unit time and better meet the requirements of real-time.Experiment results indicate that the proposed fast renormalization algorithm enables reduce the number of renormalization algorithm by 21.9%~26.7% and their corresponding run time by 14.5%~33.7%.