Robust Motion Estimation Using Complex Wavelets
نویسندگان
چکیده
This paper describes a new approach to the problem of estimating motion in video image sequences. The algorithm operates on the complex coeecients obtained by applying the new Complex Discrete Wavelet Transform to each frame. This transform implements an eecient analysis by an ensemble of Gabor-like lters of diierent orientation and scales. The Gabor-like form of the lters means that local translations induce phase rotations in the corresponding complex coeecients. This relationship is used to estimate motion at each subpixel of each scale. The estimates are combined over all orientations and scales using a coarse-tone reenement strategy to produce a fractional -pel accurate motion eld with a directional conn-dence measure. Compared with intensity-based algorithms, the new algorithm is robust to simple image formation perturbations .
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