This lecture summary deals with the low level image processing task of edge detection. Edges are discontinuities, significant local changes, in image intensities which arise from three sources: (1)projection of 3D contours (2)texture present on the 3D surfaces (3)shadows cast by the imaged objects. The summary includes the classical derivative based operators due to Canny [2], and Marr [7] and ...

0167-8655/$ see front matter 2008 Elsevier B.V. A doi:10.1016/j.patrec.2008.11.002 * Corresponding author. Tel.: +86 23 60606391; fax E-mail address: [email protected] (X. Zhang). In this paper, a new corner detector is proposed based on evolution difference of scale pace, which can well reflect the change of the domination feature between the evolved curves. In Gaussian scale space we use Di...

In this paper, we propose a novel method for feature detection of an object by fusion of range and intensity images. For this purpose, we have developed a data acquisition system with a laser source and camera interfaced with Silicon Graphics machine. 3-D mesh representation of the surface of the object is obtained from the acquired range images. Extraction of structural features from the range...

In this article, a printed Tifinagh character recognition system is presented. It is composed of three main steps: pre-processing, features extraction and classification. In the pre-processing step, binarization, normalization and thinning are applied to enhance the quality of the image. In the feature extraction step, corners are extracted using Harris Corner Detection method then represented ...

Checkerboard pattern can be used in many computer vision areas by matching the pattern as a surface, such as camera calibration, stereo vision, projector-camera system and even surface reconstruction. However, most existing checkerboard pattern recognition methods only work in planar and fine illuminating circumstances. A robust recognition method for checkerboard pattern is proposed in this pa...

Accurate detection of iris center and eye corners appears to be a promising approach for low cost gaze estimation. In this paper we propose novel eye inner corner detection methods. Appearance and feature based segmentation approaches are suggested. All these methods are exhaustively tested on a realistic dataset containing images of subjects gazing at different points on a screen. We have demo...

Several curvature estimators along digital contours were proposed in recent works [1–3]. These estimators are adapted to non perfect digitization process and can process noisy contours. In this paper, we compare and analyse the performances of these estimators on several types of contours and we measure execution time on both perfect and noisy shapes. In a second part, we evaluate these estimat...