ISITRA: A generalized way of signal decomposition and reconstruction
A new generalized way of signal decomposition and reconstruction entitled ISITRA is proposed. It is similar to the 2-channel filter bank scheme. In ISITRA, all the filters are obtained from a real vector. ISITRA allows decomposition of a signal into (1) an approximation and a detail, (2) two details and (3) two approximations. The latter two cases are not generally possible in the filter bank scheme. The choice of filter coefficients in ISITRA is much simpler and more arbitrary compared to that in the existing schemes. This allows one to find better filter coefficients for different applications. One can straight achieve an image compression ratio of 8:1 without doing any coding by modifying the range of pixel values in the decomposed components. One can also find a better set of decomposition and reconstruction filters than the commonly used Daubechies' wavelet filters of length 4. ISITRA is simpler and computationally marginally better than even the computationally efficient polyphase filter bank scheme.
signal decomposition filter banks compression wavelets perfect reconstruction polyphase scheme convolution multi-resolution analysis