计算机工程
計算機工程
계산궤공정
COMPUTER ENGINEERING
2009年
21期
222-224,227
,共4页
码率控制%比特分配%复杂度%量化参数
碼率控製%比特分配%複雜度%量化參數
마솔공제%비특분배%복잡도%양화삼수
bit rate control%bits allocation%complexity%Quantization Parameter(QP)
针对现有H.264码率控制在剧烈运动场景和场景切换时,目标比特数和量化参数计算存在的缺陷,提出一种基于帧复杂度的改进策略,根据图像序列的运动性和帧间差异显著的特点,利用帧复杂度对目标比特进行重新分配,同时利用帧的复杂度检测场景切换来调整量化参数.仿真结果表明,该方法能使目标比特数更接近实际编码的比特数,提高峰值信噪比,减少峰值信噪比的波动.
針對現有H.264碼率控製在劇烈運動場景和場景切換時,目標比特數和量化參數計算存在的缺陷,提齣一種基于幀複雜度的改進策略,根據圖像序列的運動性和幀間差異顯著的特點,利用幀複雜度對目標比特進行重新分配,同時利用幀的複雜度檢測場景切換來調整量化參數.倣真結果錶明,該方法能使目標比特數更接近實際編碼的比特數,提高峰值信譟比,減少峰值信譟比的波動.
침대현유H.264마솔공제재극렬운동장경화장경절환시,목표비특수화양화삼수계산존재적결함,제출일충기우정복잡도적개진책략,근거도상서렬적운동성화정간차이현저적특점,이용정복잡도대목표비특진행중신분배,동시이용정적복잡도검측장경절환래조정양화삼수.방진결과표명,해방법능사목표비특수경접근실제편마적비특수,제고봉치신조비,감소봉치신조비적파동.
Aiming at the shortcoming which the computation of target bits and Quantization Parameters(QP) in the situations of high motions and scene change of the existing H.264 rate control, this paper proposes a method of frame-level target bits allocation which based on the frame complexity to improve the above-mentioned two aspects. Due to the characteristic of moving image, which the differences in difference image is obvious, it uses frame complexity to re-allocation the target bits, at the same time, uses the frame complexity to detecting scene change to adjust the quantization parameters. Experimental results show that the improved algorithm can make target bits more closer to the actual bits, increase peak signal to noise ratio, decrease fluctuation of peak signal to noise ratio.
