| 摘要 |
PROBLEM TO BE SOLVED: To easily provide various reduction scales without increasing a circuit scale. SOLUTION: This filter is provided with plural delay elements 18 for successively delaying input image data GD sampled at a sampling frequency Fs by one sampling term T; a random access memory(RAM) 30 for storing N sets (three sets, for example), of coefficient groups K9-K6 for providing prescribed filtering characteristics in a reloadable form; a coefficient switching control part 32 for reading the coefficient groups K0-k6 out of the RAM 30 at the switching timing of one sampling term T, for defining M times as one cycle of repetition and at least once including respective N sets of coefficient groups in such a cycle; plural multipliers 34 for multiplying a coefficient read out of the RAM 30 to input image data GD and image data outputted from the respective plural delayers 18; and an adder 36 for adding these multiplied values, where N times of added values corresponding to N sets of coefficient groups among added values outputted M times from the adder 36 in each repetition cycle are defined as image data. |
