Halo reduction in frame-rate-conversion using hybrid bi-directional motion vectors for occlusion/disocclusion detection

Abstract

A frame-rate converter reduces halo artifacts along edges of moving objects. Halo artifacts occur on interpolated frames where a moving object covers and uncovers pixels along its edges. Motion estimation among three original frames produces hybrid direction motion vectors that are bi-directional for background and objects, but are unidirectional for covered and uncovered regions, since motion vectors with large matching errors are deleted. Covered regions in the interpolated frame are detected as intersecting only a forward but no backward hybrid motion vector. Bi-directional motion estimation from the hybrid motion vectors of two original frames produces refined motion vectors for the interpolated frame. Refined motion vectors in the covered regions are deleted and replaced with hybrid motion vectors from the original frames. Hybrid motion vectors from the original frames are assigned to the critical covered regions rather than using interpolated vectors in the covered regions, reducing halo artifacts.