Title of article :
Accurate optical flow computation under non-uniform brightness variations
Author/Authors :
Teng، نويسنده , , Chin-Hung and Lai، نويسنده , , Shang-Hong and Chen، نويسنده , , Yung-Sheng and Hsu، نويسنده , , Wen-Hsing، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2005
Abstract :
In this paper, we present a very accurate algorithm for computing optical flow with non-uniform brightness variations. The proposed algorithm is based on a generalized dynamic image model (GDIM) in conjunction with a regularization framework to cope with the problem of non-uniform brightness variations. To alleviate flow constraint errors due to image aliasing and noise, we employ a reweighted least-squares method to suppress unreliable flow constraints, thus leading to robust estimation of optical flow. In addition, a dynamic smoothness adjustment scheme is proposed to efficiently suppress the smoothness constraint in the vicinity of the motion and brightness variation discontinuities, thereby preserving motion boundaries. We also employ a constraint refinement scheme, which aims at reducing the approximation errors in the first-order differential flow equation, to refine the optical flow estimation especially for large image motions. To efficiently minimize the resulting energy function for optical flow computation, we utilize an incomplete Cholesky preconditioned conjugate gradient algorithm to solve the large linear system. Experimental results on some synthetic and real image sequences show that the proposed algorithm compares favorably to most existing techniques reported in literature in terms of accuracy in optical flow computation with 100% density.
Keywords :
Optical flow computation , Motion analysis , motion estimation , robust estimation , Brightness variation , Motion discontinuity
Journal title :
Computer Vision and Image Understanding
Journal title :
Computer Vision and Image Understanding