High speed DCT/IDCT using a pipelined CORDIC algorithm

Abstract

This paper describes DCT (IDCT) computations using the CORDIC algorithm. By rewriting the DCT, for a 1/spl times/8 DCT only 6 CORDIC computations are needed, whereas a 1/spl times/16 DCT requires 22 CORDIC computations. But these can all be pipelined through a single CORDIC unit, so 16/spl times/16 DCT's becomes feasible for HDTV compression. Only some simple adders, registers and a more complicated carry look-ahead adder are needed, end the computing speed can be very high. Limited only by the delay of a carry look-ahead adder, the delay time of the pipelined structure is 2-10 ns and the data rate as 100-500 MHz for an 8/spl times/8 DCT/IDCT and 72.2-366.6 MHz for a 16/spl times/16 DCT/IDCT when using two units.<>