The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper proposes the Anchored Kernel Metric Learning (AKML) method, which learns metrics by sparsely combining locally discriminative rank-1 basis matrices in the anchored kernel induced space. First, we apply k-means clustering to generate anchored samples, thus forming an anchored sample matrix. Based on the assumption that the basis matrices can be formulated as linear combinations of anchored...
This paper introduces a segmentation approach, where a discriminative dictionary with objects' shape information is learned, followed by a sparse representation based segmentation process. In contrast with state-of-the-art sparse representation classification methods using discriminative dictionary learning, the proposed method learns a discriminative dictionary containing both intensity and shape...
Due to its importance, figure/ground segmentation in video has gained interest recently. The key factor of the segmentation is the construction of the spatio-temporal coherence. Previous works usually use the motion approximation as a measurement of the coherence, resulting in a low accuracy. In this paper, we present a novel method to measure the coherence, and an algorithm for target segmentation...
Image alignment and stitching continue to be the topics of great interest. Image mosaicking is a key application that involves both alignment and stitching of multiple images. Despite significant previous effort, existing methods have limited robustness in dealing with occlusions and local object motion in different captures. To address this issue, we investigate the potential of applying sparsity-based...
We propose a novel computationally efficient hierarchical dictionary learning (HDL) approach for data-driven unmixing and functional connectivity analysis of functional magnetic resonance imaging (fMRI) data. It is shown that by simultaneously exploiting the sparsity of the spatial brain maps and the incoherence among their evolution in time or task functions, one can achieve better performance while...
Despite the fact that different objects possess distinct class-specific features, they also usually share common patterns. Inspired by this observation, we propose a novel method to explicitly and simultaneously learn a set of common patterns as well as class-specific features for classification. Our dictionary learning framework is hence characterized by both a shared dictionary and particular (class-specific)...
High resolution hyper-spectral imaging works as a scheme to obtain images with high spatial and spectral resolutions by merging a low spatial resolution hyper-spectral image (HSI) with a high spatial resolution multi-spectral image (MSI). In this paper, we propose a novel method based on probabilistic matrix factorization under Bayesian framework: First, Gaussian priors, as observations' distributions,...
In this paper, we propose a novel single image super-resolution (SR) method based on low-rank sparse representation with self-similarity learning. Sparse representation is known as a promising method for SR. However, the sparse codes for low resolution (LR) patches gained by conventional method are not faithful to those for the original high resolution (HR) ones. To overcome this defect, we explore...
Nonnegative matrix factorization (NMF) based hyperspectral unmixing aims at estimating pure spectral signatures and their fractional abundances at each pixel. During the past several years, manifold structures have been introduced as regularization constraints into NMF. However, most methods only consider the constraints on abundance matrix while ignoring the geometric relationship of endmembers....
Hyperspectral unmixing is an important technique for identifying the constituent spectra and estimating their corresponding fractions in an image. Nonnegative Matrix Factorization (NMF) has recently been widely used for hyperspectral unmixing. However, due to the complex distribution of hyperspectral data, most existing NMF algorithms cannot adequately reflect the intrinsic relationship of the data...
In this paper, a non-local based sparse representation (called as the NLSR) is proposed for the super-resolution of hyperspectral image. Specifically, the NLSR firstly uses the non-local Kmeans to partition pixels of low spatial resolution hyperspectral image into several classes. The non-local Kmeans can exploit the similar patterns and structures of the low spatial resolution image to enhance the...
In this paper, a robust moving camera calibration method is proposed in order to synthesize a free viewpoint soccer video with a high degree of accuracy. The main problem in video registration-based moving camera calibration is that the calibration accuracy is very low if the detected feature points are from moving objects. In order to solve this problem, the proposed method tracks the feature points...
This paper presents a fast algorithm for deriving the defocus map from a single image. Existing methods of defocus map estimation often include a pixel-level propagation step to spread the measured sparse defocus cues over the whole image. Since the pixel-level propagation step is time-consuming, we develop an effective method to obtain the whole-image defocus blur using oversegmentation and transductive...
Video analysis often begins with background subtraction, which consists of creation of a background model that allows distinguishing foreground pixels. Recent evaluation of background subtraction techniques demonstrated that there are still considerable challenges facing these methods. Processing per-pixel basis from the background is not only time-consuming but also can dramatically affect foreground...
Unsupervised segmentation and contour detection remains a challenging task. In graph-based unsupervised segmentation, the formulation of the affinity graph is pivotal to segmentation performance. Conventional graph-based approaches often only define pixels as graph nodes, and may overlook important regional information. In this paper, we propose a novel scheme for affinity graph construction, where...
Annihilating filer-based low rank Hankel matrix (ALOHA) approach was recently proposed as an intrinsic image model for image inpainting estimation. Based on the observation that smoothness or textures within an image patch are represented as sparse spectral components in the frequency domain, ALOHA exploits the existence of annihilating filters and the associated rank-deficient Hankel matrices in...
This paper proposes a novel linear hyperspectral unmixing method based on 𝑙1−𝑙2 sparsity and total variation (TV) regularization. First, the enhanced sparsity based on 𝑙1−𝑙2 norm is explored to depict the intrinsic sparse characteristic of the fractional abundances in sparse regression unmixing model. By taking the correlation between hyperspectral pixels into account, total variation is minimized...
Intrinsic image decomposition is an important topic in computer vision and computer graphics applications. However, this is a challenging problem by adopting the information of a single image. Therefore, additional priors or supplementary information such as multiply images or user interactions are necessary to address this problem. In this paper, we propose a novel scheme to use multiple images for...
Optical coherence tomography (OCT) is a medical imaging technology that allows for non-invasive diagnosis of diseases in the early stage. Because blood flow anomalies provide useful information for many diseases, we develop an automatic blood vessel detection algorithm based on the robust principle component analysis (RPCA) technique. Specifically, we propose a short-time RPCA method that divides...
Adaptive sparse representation has been heavily exploited in signal processing and computer vision. Recently, sparsifying transform learning received interest for its cheap computation and optimal updates in the alternating algorithms. In this work, we develop a methodology for learning a Flipping and Rotation Invariant Sparsifying Transform, dubbed FRIST, to better represent natural images that contain...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.