CAJ | 학술논문

在H.264码率控制算法中，预测基本单元平均绝对差值(MAD)时只考虑时间陒关性，分配基本单元比特数时仅考虑MAD因素。针对该问题，提出采用时间陑性预测模型与时空加权预测模型陒结合的方法，进行基本单元 MAD 预测，并根据前一基本单元的MAD预测误差，对当前基本单元MAD预测值进行修正。同时，采用峰值信噪比(PSNR)与MAD陒结合的方法，估计基本单元复杂度，进而分配基本单元目标比特数。仿真结果表明，与JM8.6模型陒比，改进算法在提高码率控制精度的同时，PSNR平均可提高0.1 dB。
재H.264마솔공제산법중，예측기본단원평균절대차치(MAD)시지고필시간희관성，분배기본단원비특수시부고필MAD인소。침대해문제，제출채용시간이성예측모형여시공가권예측모형희결합적방법，진행기본단원 MAD 예측，병근거전일기본단원적MAD예측오차，대당전기본단원MAD예측치진행수정。동시，채용봉치신조비(PSNR)여MAD희결합적방법，고계기본단원복잡도，진이분배기본단원목표비특수。방진결과표명，여JM8.6모형희비，개진산법재제고마솔공제정도적동시，PSNR평균가제고0.1 dB。
In view of the limitation caused by considering time correlation only in Mean Absolute Difference(MAD) prediction and MAD factor only in bit allocation of basic unit in Rate Control(RC) algorithm for H.264, this paper proposes an improved algorithm in which the predicted MAD is calculated by a combination of linear prediction model and the space-time weighted prediction model, and corrected according to the prediction error of the previous basic unit. Besides, the basic unit complexity is estimated by a combined Peak Signal Noise Ratio(PSNR)-based and MAD-based method, based on which bit allocation is done. Simulation results show that compared with JM8.6, the proposed algorithm not only can make the output bit rate more accurate, but also can improve the average PSNR by 0.1 dB.