计算机工程与应用 ›› 2011, Vol. 47 ›› Issue (14): 118-120.

• 数据库、信号与信息处理 • 上一篇    下一篇

MCLT新型快速算法

王 浩1,郑均安1,章品正2   

  1. 1.东南大学 生物科学与医学工程学院,南京 210096
    2.东南大学 计算机科学与工程学院影像科学与技术实验室,南京 210096
  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2011-05-11 发布日期:2011-05-11

Fast algorithm for Modulated Complex Lapped Transform

WANG Hao1,ZHENG Jun’an1,ZHANG Pinzheng2   

  1. 1.School of Biological Science and Medical Engineering,Southeast University,Nanjing 210096,China
    2.Lab of Image Science and Technology,School of Computer Science and Engineering,Southeast University,Nanjing 210096,China
  • Received:1900-01-01 Revised:1900-01-01 Online:2011-05-11 Published:2011-05-11

摘要: 提出了一种基本计算单元为DCT-II变换的MCLT快速算法。它将基于任意窗函数的MCLT系数的实部和虚部分别映射为一半输入序列为0的DCT-II变换。对于M点的MCLT变换,该算法只需计算两个一半输入序列为0的M点DCT-II变换和两组蝶形运算。对M点的MCLT,当窗函数为正弦窗时,提出快速算法的运算复杂度为O(MlbM);当窗函数为任意窗时,其运算复杂度为O(MlbM+2M)。实验结果表明:相对于已有的快速算法,由于该算法的中间处理过程中,一半输入序列为0,其实际计算时间减少2%以上。该算法降低了软硬件实现的存储复杂度,更符合实际应用要求。

关键词: 复数调制重叠变换(MCLT), 离散余弦变换(DCT), 窗函数, 快速算法

Abstract: A novel Discrete Cosine Transform(DCT-II) based algorithm for fast computation of the Modulated Complex Lapped Transform(MCLT) with any windows function is presented.For the MCLT of length-2M input data sequence,the proposed algorithm is based on two stages of butterfly operations and two DCT-II of length-M.The proposed algorithm involves M/2 zero points separately,thus it reduces the storage need of the hardware and decreases the computation complexity.For a length-M MCLT,the proposed algorithm requires only O(MlbM) multiplication for Sine window function and O(MlbM+2M) multiplication for any other window function.Experimental results also show that this method can reduce real computation time by 2% compared with Malvar’s algorithm.

Key words: Modulated Complex Lapped Transform(MCLT), Discrete Cosine Transform(DCT), Window function, fast algorithm