Unified inverse discrete cosine transform (IDCT) microcode processor engine

The present invention provides a unified inverse discrete cosine transform (IDCT) microcode processor engine, which is able to process IDCT with different video standards and also achieves the processing speed requirement. The microcode processor engine comprises a read unit for reading input data; a shift left unit comprising: a first shift left block for left-shifting input data; and a second shift left block for left-shifting input data; an add unit for adding data output from the shift left unit; and a shift right unit for right-shifting data output from the add unit. The present invention also provides a system of inverse discrete cosine transform.