The effect of presmoothing images on optical flow computation

• Autorzy: Condell J. , Scotneyb B. W. , Morrow P. J.

Identyfikatory

DOI

10.2478/v10248-012-0001-7

• Języki publikacji: EN

Abstrakty

EN

The computation of optical flow has been proposed as a pre-processing step for many high-level vision algorithms. One of the main approaches to the optical flow problem is the gradient-based approach which differentiates the image intensity to compute the optical flow. Often motion vectors computed using various approaches are not reliable. Spatial smoothing of the image sequence is advisable in order to improve velocity estimates in the presence of noise. That is, the application of some kind of linear operation to the images in the sequence before solving for the flow. The pre-processing typically takes the form of some type of spatial Gaussian smoothing or scale specific band-pass filtering of the input images. The main objectives of such filtering have been to lessen the effects of noise, to isolate image structure of interest and to attenuate temporal aliasing and quantization effects in the input images. This paper investigates the effect of presmoothing on this computation of optical flow. The well known method of Horn and Schunck as well as our own finite element method are implemented and tested for improvements due to presmoothing. Discussions are provided on the effects of presmoothing for a variety of image sequences. In our experiments, smoothing is carried out on a selection of five well known sequences in both time and space. Improvements are shown for many image sequences using the finite element method with presmoothing.

Słowa kluczowe

EN

optical flow computation; optical flow problem; presmoothing images; finite element method

• Wydawca: Instytut Telekomunikacji i Informatyki Uniwersytetu Technologiczno-Przyrodniczego w Bydgoszczy
• Czasopismo: Image Processing & Communications
• Rocznik: 2011
• Tom: Vol. 16, no 1-2
• Strony: 5--17
• Opis fizyczny: Bibliogr. 26 poz., tab.

Twórcy

autor

Condell J.

autor

Scotneyb B. W.

autor

Morrow P. J.

• School of Computing and Intelligent Systems, University of Ulster at Magee College, Northland Road, Londonderry, Northern Ireland

Bibliografia

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