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Structure and Motion Recovery Based on Spatial-and-Temporal-Weighted Factorization

This paper focuses on the problem of structure and motion recovery from uncalibrated image sequences. It has been empirically proven that image measurement uncertainties can be modeled spatially and temporally by virtue of reprojection residuals. Consequently, a spatial-and-temporal-weighted factorization (STWF) algorithm is proposed to handle significant noise contained in the tracking data. This paper presents three novelties and contributions. First, the image reprojection residual of a feature point is demonstrated to be generally proportional to the error magnitude associated with the image point. Second, the error distributions are estimated from a different perspective, that of the reprojection residuals. The image errors are modeled both spatially and temporally to cope with different kinds of uncertainties. Previous studies have considered only the spatial information. Third, based on the estimated error distributions, an STWF algorithm is proposed to improve the overall accuracy and robustness of traditional approaches. Unlike existing approaches, the proposed technique does not require prior information of image measurement and is easy to implement. Extensive experiments on synthetic data and real images validate the proposed method.