Implementation and Design of All Phase FIR Filter in DCT Domain
Zhaohua Wang · Journal of Tianjin University Science and Technology · 2004
Discrete cosine transform (DCT) is superior to Discrete Fourier Transform DFT,Harr Transfrom in decorrelation signals. In order to fully exploit the potential advantages of DCT in the field of signals filtering, a novel idea of 1-D all overlap frequency domain (AOFD) filter based on DCT which has strict zero phase, is proposed. The corresponding FIR model of AOFD is given. Several important characteristics as zero-phased,addictivity as to sampling sequence in frequency domain and formative multiresolution analysis with strict complementary subbands are proven in theory. Through the analysis of the image with multiresolutions, the experiment results show that AOFD is able to achieve favorable filtering effects without waveform distortion.