Reliable Estimation of Dense Optical Flow Fields with Large Displacements

In this paper we show that a classic optical ow technique by Nagel and Enkelmann (1986) can be regarded as an early anisotropic di usion method with a di usion tensor. We introduce three improvements into the model formulation that (i) avoid inconsistencies caused by centering the brightness term and the smoothness term in di erent images, (ii) use a linear scale-space focusing strategy from coarse to ne scales for avoiding convergence to physically irrelevant local minima, and (iii) create an energy functional that is invariant under linear brightness changes. Applying a gradient descent method to the resulting energy functional leads to a system of di usion{reaction equations. We prove that this system has a unique solution under realistic assumptions on the initial data, and we present an e cient linear implicit numerical scheme in detail. Our method creates ow elds with 100 % density over the entire image domain, it is robust under a large range of parameter variations, and it can...

• Type: Journal
• Year: 2000
• Where: IJCV
• Authors: Luis Álvarez, Joachim Weickert, Javier Sánchez
• Keywords: Classic Optical Ow, Di Usion, IJCV 2000, Optical Ow