S. Negahdaripour. Revised definition of optical flow: Integration of radiometric and geometric cues for dynamic scene analysis. PAMI, 20(9):961--979, 1998.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....hand postures directly from the images after learning the mapping from image feature space to hand configuration space [30, 29] Such systems are more useful for recognizing discrete hand states than for general purpose hand tracking. The study of motion and shading together has been formalized [20, 22] recently and extended to multiple views [21] Our approach is model based and hence can work with a single view. Our first contribution is in the combination of cue forces from edges, optical flow and shading. In particular we introduce in deformable model theory a generalized version of the ....

Negahdaripour, S., Revised Definition of Optical Flow: Integration of Radiometric and Geometric Cues for Dynamic Scene Analysis, PAMI(20), No. 9, Sep. 1998, pp. 961-979

....variations. Our framework extends several previous approaches that generalize the brightness constancy assumption. Mukawa [31] extended the brightness constancy assumption to allow illumination changes that are a smoothly varying function of the image brightness. In a related paper, Negahdaripour [34] proposed a general linear brightness constraint I (x, t ) m(x, t )I (x u(x) t 1) c(x, t ) 2) where m(x, t ) and c(x, t ) allow for multiplicative and additive deviations from brightness constancy and are assumed to be constant within an image region. Another generalization of ....

S. Negahdaripour. Revised definition of optical flow: Integration of radiometric and geometric cues for dynamic scene analysis, IEEE Trans. Pattern Anal. Machine Intell. 20, 1998, 961--979.

....changes or other violations of the optical flow constraint equation. Solutions to these problems can come on two fronts. First would be to model the situation better; for instance, using a more general form of the optical flow constraint equation to take radiometric variations into account [20]. Second, and perhaps more generally applicable, would be the use of robust techniques for cue integration, which expect some (but not all) cues or computations to fail at any time [17] 6 Conclusions We have presented a novel deformable model technique which uses residuals from a model based ....

S. Negahdaripour. Revised definition of optical flow: Integration of radiometric and geometric cues for dynamic scene analysis. IEEE Pattern Analysis and Machine Intelligence, 20(9):961--979, September 1998.

....With only two frames, one can only model brightness changes that are linear in time. 2 IEEE Conference on Computer Vision and Pattern Recognition (CVPR) Hilton Head Island, SC, June 2000 If brightness is not conserved, then the optical flow field estimated from (2) can be severely biased [4, 17, 18, 24, 3, 20, 9, 19]. Causes of brightness variation include moving illumination envelopes, changing orientation of surfaces under directional illumination, and atmospheric influences in outdoor applications. Other instances occur in scientific applications that quantitatively investigate dynamic processes [13] ....

....estimates, and it allows us to estimate additional information that characterizes the physical processes. TLS error covariance matrices [21] are used to quantify the accuracy of the optical flow and the brightness change parameters. 2. Previous Work Brightness variations have been modeled by [4, 17, 18, 24, 3, 20, 9]. A general framework is proposed in [20] where the brightness change between two frames consists of a multiplier and an offset field: ### # ## # #### # ############## (3) where, for notational convenience, # # # # # ## # # denotes a space time 3D vector. It is certainly true that all ....

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S. Negahdaripour. Revised definition of optical flow: integration of radiometric and geometric clues for dynamic scene analysis. IEEE Trans. PAMI, 20(9):961--979, 1998.

....optical flow within a small spatial neighborhood, and conservation of image brightness along the path of objects. Our approach weakens these strong conservation laws and allows parameterized variations of both the motion field and the image brightness. In contrast to other approaches (e.g. 9] [11], 3] temporal brightness variations of higher than linear order are allowed. Hence, the spatiotemporal image structure is analyzed in an entirely symmetric way with respect to spatial and temporal coordinates. A major contribution of this paper is the generalized framework for incorporating ....

....find the directions of brightness changes following the corresponding functional relationship, instead of searching iso brightness lines in the spatiotemporal neighborhood. In the most simple case, the brightness change is known to be linear, consisting of an o#set and multiplier field. In [3] and [11] it is shown, that a variety of radiometric transformations can be cast into a linear relationship. It is also evident, that slow brightness variations can be expressed as linear changes in a first order approximation. In scientific applications, however, dynamic transport processes can lead to ....

Negahdaripour, S.: Revised definition of optical flow: integration of radiometric and geometric clues for dynamic scene analysis. IEEE PAMI, 20(9), (1998) 961-979

....variation, i.e. b a = # # # # # # # D o oo D (2) Note that the constants a and b are the illumination multiplication and bias factors. However, this model cannot account for spatially varying illumination variations. To overcome this restriction, a generalized dynamic image model [6] is proposed by assuming the illumination multiplication and bias factors ( a and b ) to be functions of location # # # . In this paper, we assume these two illumination factors are slowly varying functions of location # # # , thus they can be well approximated by low order polynomials of ....

S. Negahdaripour, "Revised definition of optical flow: integration of radiometric and geometric cues for dynamic scene analysis," IEEE Trans. Patt. Anal. Mach. Intel., Vol. 20, No. 9, pp. 961-979, 1998.

....variations. Our framework extends several previous approaches that generalize the brightness constancy assumption. Mukawa [31] extended the brightness constancy assumption to allow illumination changes that are a smoothly varying function of the image brightness. In a related paper, Negahdaripour [34] proposed a general linear brightness constraint I(x; t) m(x; t)I(x Gamma u(x) t 1) c(x; t) 2) where m(x; t) and c(x; t) allow for multiplicative and additive deviations from brightness constancy and are assumed to be constant within an image region. Another generalization of ....

S. Negahdaripour. Revised definition of optical flow: Integration of radiometric and geometric cues for dynamic scene analysis. IEEE Transactions on Pattern Analysis and Machine Intelligence, 20(9):961--979, September 1998.

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S. Negahdaripour. Revised definition of optical flow: Integration of radiometric and geometric cues for dynamic scene analysis. PAMI, 20(9):961--979, 1998.

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S. Negahdaripour. Revised definition of optical flow: Integration of radiometric and geometric cues for dynamic scene analysis. IEEE Trans. Pattern Anal. Machine Intell., 20(9):961--979, Sept. 1998.

No context found.

S. Negahdaripour. Revised definition of optical flow: Integration of radiometric and geometric cues for dynamic scene analysis. PAMI, 20(9):961--979, Sept. 1998.

No context found.

S. Negahdaripour. Revised definition of optical flow: Integration of radiometric and geometric cues for dynamic scene analysis. PAMI, 20(9):961--979, 1998.

No context found.

S. Negahdaripour, "Revised definition of optical flow: integration of radiometric and geometric cues for dynamic scene analysis," IEEE Trans. Pattern Anal. Machine Intell., vol. 20, no. 9, pp. 961--979, September 1998.

No context found.

Negahdaripour, S. (1998). Revised definition of optical flow: Integration of radiometric and geometric cues for dynamic scene analysis. IEEE Trans. PAMI 20 (9), 961--979.

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