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We propose a simple but powerful method for tracking a nonparameterized subject contour in a single video stream with a moving camera and changing background for the purpose of video background removal to capture motion in a scene. Our method is based on level-of-detail (LOD) modified Canny edge maps and graph-based routing operations on the LOD maps. We generated modified Canny edge maps by computing...
A new kind of rotation moment invariants suitable for recognition of symmetric objects is presented. They are composed of complex moments of the image and their invariance to rotation is achieved by multiplicative phase cancellation. Unlike earlier moment invariants they explicitly consider the degree of symmetry of the objects. Thanks to this, they do not vanish on symmetric objects and are able...
The concept of fuzzy segment was introduced in [2]. In this paper we suggest a notion of strict fuzzy segment and provide a linear algorithm for recognizing it thanks to a simple property of convex hull. A linear method to decompose a thick curve into strict fuzzy segments is also given. The quality of decomposition can be easily controlled by setting two threshold values: the maximum order and the...
Many problems in image representation and classification involve some form of dimensionality reduction. Non-negative matrix factorization (NMF) is a recently proposed unsupervised procedure for learning spatially localized, parts-based subspace representation of objects. Here we present an improvement of the classical NMF by combining with Log-Gabor wavelets to enhance its part-based learning ability...
In this paper, we propose a new method to capture user’s focused iris image at fast speed based on the corneal specular reflection and the human eye model. Experimental results show that the focused iris image acquisition time for the users with and without glasses is 450 ms on average and our method can be used for a real-time iris recognition camera.
The contribution presents an integrated system for automatic acquisition of a human torso model, using different input images. The output model consists of two free-form surface patches (with texture maps) for the torso and the arms. Also, the positions for the neck joint on the torso, and six joint positions on the arms (for the wrist, elbow and shoulder) are determined automatically. We present...
This paper proposes a new method to solve the problem of face recognition under varying illumination conditions. We introduce an exemplar-based technique to decouple and subsequently recover the canonical face and the illumination functions from the intensity images. The canonical image is equivalent to the reflectance field of the face that is invariant to illumination. We subsequently use the canonical...
In this paper, dealing with the case of large movements in active vision applications, we first develop an algorithm to estimate the motion of an object and its background. Furthermore, with the assumption of small translations between successive frames, we develop an active tracking algorithm. Its main advantage is that an area-based projection method is presented which resorts to an area integral...
An important aspect of fingerprint verification systems is the method used to quantify the similarity between two fingerprints. This involves two key components: choosing fingerprint features that will be used for comparison and selecting a match score function to calculate the degree of correspondence. The choice of features and a match score function can have a significant impact on the performance...
This paper presents a novel approach to modelling fingerprint deformations. When fingerprints are captured, they undergo a certain amount of distortion due to the application of a three dimensional elastic tissue against a flat surface. This poses a challenge for automated fingerprint verification systems, which are generally based on aligning two fingerprints and comparing their respective features...
AIRS classification algorithm, which has an important place among classification algorithms in the field of Artificial Immune Systems, has showed an effective and intriguing performance on the problems it was applied. In this study, the resource allocation mechanism of AIRS was changed with a new one determined by Fuzzy-Logic rules. This system, named as Fuzzy-AIRS and AIRS were used as classifiers...
We propose a technique to compute the fraction of boar spermatozoid heads which present an intracellular density distribution pattern hypothesized as normal by veterinary experts. This approach offers a potential for digital image processing estimation of sperm capacitation which can substitute expensive staining techniques. We extract a model distribution from a training set of heads assumed as normal...
In this paper we describe a new mesh parametrization method which combines the mean value coordinates and the Locally Linear Embedding (LLE) method. The mean value method is extended to compute the linearly reconstructing weights of both the interior and the boundary vertices of a 3D triangular mesh, and the weights are further used in the LLE algorithm to compute the vertex coordinates of a 2D planar...
This paper focuses on variational image analysis on a sphere. Since a sphere is a closed Riemannian manifold with the positive constant curvature and no holes, a sphere has similar geometrical properties with a plane, whose curvature is zero. Images observed through a catadioptric system with a conic-mirror and a dioptric system with fish-eye lens are transformed to images on the sphere. Therefore,...
Digital photogrammetric processing of aerial and space stereo images acquired with CCD-line scanners is widely used in today’s remote sensing, surveying, and mapping of the Earth’s surface. Because of considerable geometric distortions due to movements of a scanner platform, the acquired images have to be corrected before processing. A conventional approach consists of sequential correction and terrain...
We propose a new content-based image retrieval method using the color and pattern histogram that is adaptive to the block classification characteristics. In the proposed method, the color and pattern feature vectors are extracted according to the characteristics of the block classification after dividing an image into the blocks with a fixed size. Specifically, the adaptive representative color histograms...
This paper exploits the properties of the commute time to develop a graph-spectral method for image segmentation. Our starting point is the lazy random walk on the graph, which is determined by the heat-kernel of the graph and can be computed from the spectrum of the graph Laplacian. We characterise the random walk using the commute time between nodes, and show how this quantity may be computed from...
This paper presents a color filter array (CFA) image indexing approach. To enhance the functionality of single-sensor consumer electronics such as digital cameras, imaging-enabled mobile phones and wireless personal digital assistants (PDAs), the proposed solution embeds the metadata information to a CFA image using a common discrete cosine transform (DCT) based watermarking scheme. Depending on a...
In this article we present an algorithm for computing discrete average of n two-dimensional shapes. Our previous work was limited to two shapes, we generalize it to an arbitrary number of objects with consideration of increasing inter-individual variability. The first step of our approach performs a rigid transformation that aligns the shapes as best as possible. The next step consists in searching...
We present a coupled statistical model that can be used to accurately recover facial surfaces from single images by jointly capturing variations in surface normal direction and surface height. The model is trained on range data. By fitting the model to surface normal data, the surface height function is implicitly recovered without having to integrate the recovered field of surface normals. We show...
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