DISCRETE COSINE FORWARD AND REVERSE TRANSFORMATION DEVICE

摘要

PURPOSE:To make the device small and to reduce the power consumption by using an arithmetic ROM in common for forward and reverse transformation. CONSTITUTION:Let eight inputs be (a)-(h), then ROM 501, 505 receiving two inputs (a), (b) output a prescribed arithmetic result. Similarly, ROM 502, 506, 509, 512 receives inputs (c), (d) and output processing arithmetic result, ROM 503, 507, 510, 513 receives inputs (e), (f) and output processing arithmetic result, and ROM 504, 508 511, 514 receives inputs (g), (h) and output processing arithmetic result respectively. Moreover, outputs of the ROM 503 and the ROM 504, the ROM 507 and the ROM 508, the ROM 510 and the ROM 511, and the ROM 513 and the ROM 514 are added respectively by adders 601-602. Ten outputs 80 are outputted by IDCT arithmetic operation and eight bypass outputs 81 are outputted as DCT arithmetic processing.