基于H.264高档次标准的一种新颖的8×8/4×4SATD硬件实现

Novel Hardware Implementation of 8×8/4×4 SATD Based on H.264 High Profile

支持8×8/4×4自适应变换是H.264高档次标准的一个重要特性,残差变换绝对值和(sumof absolute transformed difference,SATD)是各种模式下预测残差代价的评判准则。根据SATD的运算特点,提出一种高度并行的流水线结构,通过两级1-D变换实现2-D哈达码变换。采用3-2压缩器代替传统的加法器实现和值相加,提高了运算速度。在SMIC 0.13μm CMOS工艺库下的实验结果表明,利用上述思想设计的4×4 SATD以及8×8 SATD电路在300 MHz的时钟频率下每秒钟处理的像素数分别为4.8G和19.2G,远远超过了高清视频应用中1920×1080视频序列30帧/s的实时编码需求。

Supporting that adaptive 8×8/4×4 transform is an important feature of H.264 high profile,the sum of absolute transformed difference（SATD） is used as the judging criteria for the prediction residue cost of each mode.According to SATD＇s computation characteristics,this paper proposes a high-paralleled pipelined architecture.One 2-dimension（2-D） hadamard transform can be implemented by two 1-D hadamard transforms.In addition,4-2 compressor instead of the traditional adder is employed to improve the transformation speed.Using a 0.13μm CMOS technology,the proposed 4×4 SATD and 8×8 SATD architectures can process 4.8G pixels/s and 19.2G pixels/s respectively at the clock frequency of 300MHz,which is well above the requirement of the HDTV（1920×1080,30fps） real time encoding for the high definition video surveillance application.