摘要
以PC机为硬件平台对MPEG-2的音频解码算法进行优化,实现MPEG-2全软件的系统、视频、音频3个部分实时解码。在IDCT和IMDCT中应用了新的快速算法;结合PC机本身的特点及解码过程中有大量的乘加运算采用SIMD(single-instructionmultiple-data)来对程序优化,并在实际运算中也对数据结构进行了优化。通过以上的优化使MPEG-2层II解码的运算量减少了40%以上,在奔腾3/450计算机上只占用不到5%的系统资源。这些优化算法已经应用于奔腾3/800为硬件平台的MPEG-2实时解码器中。
This paper presents an optimized audio algorithm of MPEG-2decoding with an Intel Pen-tium PC platform under Window's OS.The novel fast IDCT,IMDCT transform algorithms are adopted,and combined with the characteristics of Intel Pentium PC the single-instruction multiple-data(SIMD)techniques are applied in operations such as multiplication,addition and etc.Furthermore,the opti-mized data structure have been adopted in practical optimization procedure.With all these optimization methods,the audio decoding of MPEG-2layer2can decrease more than40%operations and expenses less than5%system resource of PIII450.These optimized algorithms have been applied in a MPEG2real time coding under a PentiumIII800platform.[
出处
《电声技术》
北大核心
2003年第12期10-12,22,共4页
Audio Engineering
基金
国家自然科学基金(69972020)
国家基础研究项目(G1998030406).
关键词
MPEG-2
音频解码
SIMD
离散余弦反变换
修正离散余弦反变换
单指令多数据
audio decode
algorithm optimization
inverse discrete cosine transform(IDCT)
inverse modified discrete cosine transform(IMDCT)
single-instruction multiple-data(SIMD)
