On smoothness of a vector field-application to optical flow

Two measures of smoothness of a vector field over a domain are suggested, together with associated smoothing operators that satisfy given constrains. The technique is illustrated using operators that smooth the invariants of optical flow curl and divergence, estimated from intensity profiles of moving nondeformable objects. The operators have been applied with satisfactory results to derived flow estimates with high noise levels.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>