Coefficient-free and high-accuracy recursive kernel design for forward and inverse transforms of MDST and MDCT

This paper presents an efficient recursive architecture for realizing modified discrete cosine transform (MDCT), modified discrete sine transform (MDST), inverse MDCT (IMDCT), and inverse MDST (IMDST) computations. After employing the data rearrangement and a coefficient-free algorithm, the computations MDCT, MDST, IMDCT and IMDST can be represented as a modified type-II of inverse discrete sine transform (Modified IDST-II), which can be further realized into a second-order infinite-impulse response (IIR) filter. The analytic results show that the proposed recursive structure has some advantages in terms of lower computational cycles and higher data transformation throughput rate compared with the conventional work. It would be a better solution for the applications of various audio compression techniques in the future.