| 摘要 |
<p>PURPOSE:To perform the fast discrete cosine transformation(DCT) processing with a small amount of hardware. CONSTITUTION:The discrete cosine transformation processing device which obtains a discrete cosine transformation coefficient and an inverse cosine transformation efficient from prescribed input data is provided with 8 independent selecting circuits 140 to 147 which select one data from 8 input data a0 to a7 as a select signal, 7 coefficient multipliers 150 to 156 which are connected to outputs of selecting circuits and multiply select signals b0 to b7 by coefficient P1 to P7 different from one another, and 5 adder/subtractors 161 to 165 which add and substract the outputs of coefficient multipliers in various combinations. Adder/subtractors 161 to 163 out of these 5 adder/substractors are used for cosine transform, and the other adder/subtractors 164 and 165 are used for inverse transformation, and the data selecting method in selecting circuits and selection of addition or subtraction in adder/subtractors are switched four times to calculate eight cosine transformation coefficients.</p> |
