A MODE-CHANGEABLE 2-D DCT IDCT PROCESSOR FOR DIGITAL VCR/

In a digital VCR, DCT/IDCT is performed by both 8x8 mode and 2x4x8 mod e to improve coding efficiency, In this paper, a new 2-D DCT/IDCT proc essor which requires minimal hardware overhead for 8x8/2x4x8 mode chan ge for digital VCR is presented. The proposed DCT/IDCT processor uses a concurrent architecture and executes both DCT and IDCT with 8x8 and 2x4x8 mode selection. This chip is implemented on the basis of the row -column decomposition scheme. The proposed architecture minimizes hard ware overhead for 2x4x8 mode by sharing the same datapath with 8x8 mod e as much as possible. The proposed architecture also reduces the hard ware and the chip size by exploiting the table look-up method instead of the extra multiplication circuits in the weighting coefficients han dling. The implemented DCT/lDCT processor satisfies the accuracy speci fication of digital VCR.