IMAGE PROCESSING UNIT

摘要

PROBLEM TO BE SOLVED: To allow a processing unit to process reverse quantization and 2-dimension IDCT(reverse discrete cosine transformation) at a high speed. SOLUTION: A quantization DCT coefficient Rvu is given to a pre-processing section N1, in which the coefficient is multiplied by a quantization multiplier term table to obtain a pre-processing DCT coefficient Hvu. The quantization multiplier term table is generated by multiplying the quantization coefficient by a multiplier term corresponding to a part of 2-dimension IDCT. The pre- processing DCT coefficient Hvu is given to 1st to 4th stages T1, T2, T3, T4 being components of a post-processing section (IDCT engine) N2, and processing corresponding to the multiplication of a prescribed DCT coefficient Fvu is conducted in the stages T1-T4. Output data in the respective stages T1-T4 are integrated and the remaining processing of the 2-dimension ICDT is conducted to obtain 64 sets of picture element values Pyx of 8×8 picture elements.