PURPOSE: To highly accurately and quickly execute Wavelet transformation.
CONSTITUTION: Convolution operation between input data S0 and a Gabor function G is executed by an operation part 20 to obtain the 0-th stage Wavelet coefficient Tg (2o, b). The input data S0 are applied to a low pass filter(LPF) 30 and filtered by a Gaussian filter so as to be converted into 1st stage input data S1 in which the frequency of a high frequency component is reduced to 1/2. Convolution operation between the input data S1 and the Gabor functions Gα/3, 2ω/3 is executed by an operation part 21 to obtain a 1st stage coefficient Tg (21, b). The sampling interval of the 1st stage convolution operation is twice the 0-th stage. Since the sampling interval of operation in the succeeding stage is increased every twice, the quantity of operation in each stage is not increased and the coefficient Tg (2j, b) can be found out with the same accuracy in respective stages.
SANNOMIYA KIMIE
UCHIDA TAKANOBU
NUMATA TOSHIHARU
