The way adopted pipeline architecture and changed 2-D DCT/IDCT to two 1-D DCT/IDCT based on characteristic of row-column decomposition.

该方案利用DCT的行列分离特性，采用流水线设计技术，将二维DCT/IDCT实现转化为两个一维DCT/IDCT实现。

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First, the 2-d IDCT is transformed into two cascaded 1-d IDCT. Then 1-d IDCT can be implemented by multiplication and addition of matrix according to butterfly computation.

首先将二维idct转换为两个一维idct变换，根据蝶形算法进一步转换为矩阵的乘加运算。

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