Patent ID: 8145695

Claim:
A time-domain to frequency-domain signal processing method, comprising: pre-processing time-domain data by a pre-processing unit programmed on a super wideband audio encoder; pre-rotating the pre-processed data by a pre-rotating unit, programmed on a super wideband audio encoder using a rotation factor a·W N n+0.5 ; performing a discrete Fourier transform (DFT) of N/4 points on the pre-rotated data; and post-rotating the data transformed by the DFT by using a rotation factor b·W N k+0.5 to obtain frequency-domain data; where: a and b are constants, N is the length of the time-domain data, W N = ⅇ - j ⁢ 2 ⁢ π N , W N n + 0.5 = ⅇ - j ⁢ 2 ⁢ π N ⁢ ( n + 0.5 ) , ⁢ W N k + 0.5 = ⅇ - j ⁢ 2 ⁢ π N ⁢ ( k + 0.5 ) , ⁢ n = 0 , … ⁢ , N 4 - 1 ⁢ ⁢ and ⁢ ⁢ k = 0 , … ⁢ , N 4 - 1.