| 摘要 |
To implement processing for plural orthogonal transforms having different transform bases and implement a response to processing in new coding standards, using one orthogonal transform unit, with regard to orthogonal transform which is a basic process in still picture and moving picture coding. An orthogonal transform apparatus includes: a first butterfly calculating unit (100) having a two-input basic calculating unit performing two-input product-sum calculation on part of input signals; a second butterfly calculating unit (101) having a four-input basic calculating unit performing four-input product-sum calculation on remaining input signals; a third butterfly calculating unit (102) in a subsequent stage to the second butterfly calculating unit, having a 2-point basic calculating unit performing 2-point product-sum calculation; first, second delaying units (203, 202) and so on, in subsequent stages to the first, third butterfly calculating units (100, 102) and so on, respectively; a fourth butterfly calculating unit (103) having a two-input basic calculating unit performing two-input product-sum calculation on data selected by first, second selecting units (303, 302) and so on; and a transform coefficient supplying unit (401). In the orthogonal transform apparatus, the product-sum calculations performed by the four-input basic calculating unit can be switched. |
