Coherent Parametric Contours for Interactive Video Object Segmentation

Interactive video segmentation systems aim at producing sub-pixel-level object boundaries for visual effect applications. Recent approaches mainly focus on using sparse user input (i.e. scribbles) for efficient segmentation, however, the quality of the final object boundaries is not satisfactory for the following reasons: (1) the boundary on each frame is often not accurate, (2) boundaries across adjacent frames wiggle around inconsistently, causing temporal flickering, and (3) there is a lack of direct user control for fine tuning. We propose Coherent Parametric Contours, a novel video segmentation propagation framework that addresses all the above issues. Our approach directly models the object boundary using a set of parametric curves, providing direct user controls for manual adjustment. A spatiotemporal optimization algorithm is employed to produce object boundaries that are spatially accurate and temporally stable. We show that existing evaluation datasets are limited and demonstrate a new set to cover the common cases in professional rotoscoping. A new metric for evaluating temporal consistency is proposed. Results show that our approach generates higher quality, more coherent segmentation results than previous methods.