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Archive for the 'papers' Category

Methods for Geometrical Video Projector Calibration

J. Draréni, P.F. Sturm and S. Roy. In, Machine Vision and Applications Journal (MVA), January 2012, Volume 23, Issue 1, pp 79-89. In this paper we present two methods to geometrically calibrate a video projector using a markerless  planar surface. The first method assumes a partial knowledge on the camera parameters whereas the  second method […]

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Plane-Based Calibration for Linear Cameras

J. Draréni, P.F. Sturm and S. Roy, in International Journal of Computer Vision, Volume 91, Number 2, pages 146-156, 2011. Linear or 1D cameras are used in several areas such as industrial inspection and satellite imagery.Since 1D cameras consist of a linear sensor, a motion (usually perpendicular to the sensororientation) is performed in order to […]

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Indoor Calibration using Segments Chains

  J. Draréni, R. Keriven, and R. Marlet In this paper, we present a new method for line segments matching for indoor reconstruction. Instead of matching individual seg- ments via a descriptor like most methods do, we match segment chains that have a distinctive topology using a dynamic programing formula- tion. Our method relies solely […]

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Fast probabilisitic estimation of egomotion from image intensities

  J. Draréni, N. Martin, S. Roy This paper proposes a real-time probabilistic solution to the problem of camera motion estimation in a video se- quence. Instead of using explicit tracking of features, it only uses instantaneous image intensity variations without prior estimation of optical flow. We represent the cam- era motion as a probability […]

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Bas-Relief Ambiguity Reduction in Shape from Shadowgrams.

J. Draréni, P.F. Sturm and S. Roy. Coplanar shadowgrams provide an affordable mean to retrieve the 3d shape of an object especially when classi- cal stereopsis fails (eg:textureless objects). Its principles are similar to the concepts used for Shape-From-Silhouettes with the only exception that here, light sources and cam- eras are interchanged. However, it is […]

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Projector Auto-Calibration

J. Draréni, S. Roy and P. Sturm In this paper we address the problem of geometric calibration of video projectors. Like in most previous methods we also use a camera that observes the projection on a planar surface. Contrary to those previous methods, we neither require the camera to be calibrated nor the presence of […]

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Projector Calibration using a Markerless Plane

J. Draréni, S. Roy and P. Sturm. In this paper we address the problem of geometric video projector calibration using a markerless planar surface (wall) and a partially calibrated camera. Instead of using control points to infer the camera-wall orientation, we find such relation  by efficiently sampling the hemisphere of  possible orientations. This process is […]

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Plane-Based Calibration for Linear Cameras.

J. Draréni, P.F. Sturm and S. Roy. Linear or 1D cameras are used in several areas such as industrial inspection and satellite imagery. Since 1D cameras consist of a linear sensor, a motion (usually perpendicular to the sensor orientation) is performed in order to acquire a full image. In this paper, we present a novel […]

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A Simple Oriented Mean-Shift Algorithm For Tracking.

J. Draréni and S. Roy. Mean-Shift tracking gained a lot of popularity in computer vision community. This is due to its simplicity and robustness. However, the original formulation does not estimate the orientation of the tracked object. In this paper, we extend the original mean-shift tracker for orientation estimation. We use the gradient field as […]

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