TY - JOUR

T1 - Tilings of the Time-Frequency Plane

T2 - Construction of Arbitrary Orthogonal Bases and Fast Tiling Algorithms

AU - Herley, Cormac

AU - Kovacevic, Jelena

PY - 1993/12

Y1 - 1993/12

N2 - We consider expansions which give arbitrary orthonormal tilings of the time-frequency plane. These differ from the short-time Fourier transform, wavelet transform, and wavelet packets tilings in that they change over time. We show how this can be achieved using time-varying orthogonal tree structures, which preserve orthogonality, even across transitions. The method is based on the construction of boundary and transition filters; these allow us to construct essentially arbitrary tilings. Time-varying modulated lapped transforms are a special case, where both boundary and overlapping solutions are possible with filters obtained by modulation. We present a double-tree algorithm which for a given signal decides on the best binary segmentation in both time and frequency. That is, it is a joint optimization of time and frequency splitting. The algorithm is optimal for additive cost functions (e.g., rate-dis-tortion), and results in time-varying best bases, the main application of which is for compression of nonstationary signals. Experiments on test signals are presented.

AB - We consider expansions which give arbitrary orthonormal tilings of the time-frequency plane. These differ from the short-time Fourier transform, wavelet transform, and wavelet packets tilings in that they change over time. We show how this can be achieved using time-varying orthogonal tree structures, which preserve orthogonality, even across transitions. The method is based on the construction of boundary and transition filters; these allow us to construct essentially arbitrary tilings. Time-varying modulated lapped transforms are a special case, where both boundary and overlapping solutions are possible with filters obtained by modulation. We present a double-tree algorithm which for a given signal decides on the best binary segmentation in both time and frequency. That is, it is a joint optimization of time and frequency splitting. The algorithm is optimal for additive cost functions (e.g., rate-dis-tortion), and results in time-varying best bases, the main application of which is for compression of nonstationary signals. Experiments on test signals are presented.

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U2 - 10.1109/78.258078

DO - 10.1109/78.258078

M3 - Article

AN - SCOPUS:0027806249

VL - 41

SP - 3341

EP - 3359

JO - IEEE Transactions on Signal Processing

JF - IEEE Transactions on Signal Processing

SN - 1053-587X

IS - 12

ER -