An Iterative Method for Signal Extension in Subband Coding
نویسندگان
چکیده
One key problem in subband and wavelet coding systems, is the decomposition of limited size signals. The Wavelet transform is defined for infinitelength signals. In practice we only have finite-length signals, so signals must be extended before they can be transformed. The question is how to extend the signal to minimize signal end effects, or how to find the signal extension that preserves the transform signal length. In this paper we discuss the problem of signal extension in perfect reconstruction filter banks. We present a new iterative method to extend the input signal, for any kind of filter bank (non-linear phase or liner phase) and for any type of extension before the synthesis filter bank. The synthesis extension can be zero padding, replication of boundary values, symmetric extension or any type of linear extension.
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تاریخ انتشار 1999