A fast IMDCT algorithm for MPEG-2 AAC decoder
Hua-Jun Chi, Tae-Hoon Kim, Koon-Shik Cho, Jusung Park · ITC-CSCC :International Technical Conference on Circuits Systems, Computers and Communications · 2007
This paper proposes a new IFFT(Inverse Fast Fourier Transform) algorithm, which is proper for IMDCT((Inverse Modified Discrete Cosine Transform) of MPEG-2 AAC(Advanced Audio Coding) decoder. The IFFT used in 2 N -point IMDCT employ the bit-reverse data arrangement of inputs and N/4-IFFT to reduce the calculation cycles. We devised a new data arrangement algorithm of IFFT input and N/4ⁿ?¹-IFFT and can reduce multiplication cycles, addition cycles, and ROM size.