Bilinear Algorithms and VLSI Implementations of Forward and Inverse MDCT with Applications to MP3 Audio (Technology#: 010408-03)

Professionals in the music and movie industries are constantly looking for quicker audio processing techniques. Forward and inverse modified discrete cosine transforms (MDCT/IMDCT) are used for the practical applications of hardwired circuiting for MP3 audio encoding and decoding.The given technology uses bilinear algorithms to compute (MDCT/IMDCT) through Type-IV discrete sine transform (DCT-IV). Three different versions of unified hardware architectures for both the short and long blocks are proposed such that the efficiency of the overall encoding/decoding process is increased.

ADVANTAGES

MP3 audio processing computations previously required code specific to the frame size. The algorithm used here is able to solve the problem by unifying the MDCT computations, thereby yielding a smaller code which requires less memory.

• Efficient bilinear algorithms for MDCT and IMDCT of both short and long block sizes
• Improved critical path delay of VLSI architecture for MDCT and IMDCT of both short and long block sizes (20% to 30% faster circuit)
• Type-(1x) unified algorithm and architecture for MP3 audio (forward/inverse and short/long), capable of processing 1 long block or 1 short block per cycle
• With pipelined architecture, the number of outputs can be reduced by 1/3, further improving the silicon footprint

APPLICATIONS

• MP3 audio encoding and decoding
• Fast signal processing

STATUS OF INTELLECTUAL PROPERTY

A Patent Cooperation Treaty (PCT) application has been filed.