Confident adaptive algorithms are described, evaluated,and compared with other algorithms that implement the estimationof motion. A Galerkin finite element adaptive approach isdescribed for computing optical flow, which uses an adaptive triangularmesh in which the resolution increases where motion is found tooccur. The mesh facilitates a reduction in computational effort by enablingprocessing to focus on particular objects of interest in a scene.Compared with other state-of-the-art methods in the literature ouradaptive methods show only motion where main movement is knownto occur, indicating a methodological improvement. The mesh refinement,based on detected motion, gives an alternative to methodsreported in the literature, where the adaptation is usually based on agradient intensity measure. A confidence is calculated for the detectedmotion and if this measure passes the threshold then themotion is used in the adaptive mesh refinement process. The idea ofusing the reliability hypothesis test is straightforward. The incorporationof the confidence serves the purpose of increasing the opticalflow determination reliability. Generally, the confident flow seemsmost consistent, accurate and efficient, and focuses on the mainmoving objects within the image.
|Journal||International Journal of Imaging Systems and Technology|
|Publication status||Published (in print/issue) - 22 Sept 2006|
Bibliographical noteThis paper examines reliability measures for optical flow computation in the context of previous work – the development of adaptive grid refinement approaches – and demonstrates the incorporation of confidence measures into the computational algorithm to increase accuracy. Extensive analysis and experimentation were performed against benchmark image sequences. The work has been taken forward into technology transfer activities with funding from the Higher Education Innovation Fund to develop a vision system to analyse live video from a single camera, and funding from the EU INTERREG IIIA programme to develop a motion analysis system for hand gestures in 3D character model animation.
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- adaptive grids
- confidence measures
- finite element methods
- optical flow