1. A method for running an audio decoding algorithm on programmable processors, comprising the steps of: authorizing operation signals for the pre-processing of IMDCT operation used by the filter bank based on the amount of operations of the MPEG-2/4 AAC algorithm; generating two addresses in one address register by a specific address generating rule; reading the data from the data memory and ROM memory; and running the butterfly operations necessary to the pre-process in parallel.