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In this paper, we propose a novel camera motion estimation algorithm for mobile platforms. Videos captured by cameras mounted in mobile platforms suffer from jitter motions caused by various factors. It is vital to obtain accurate estimates of camera motions in order to remove these undesirable jitters. But existing motion estimation methods for mobile platforms have difficulties to deal with the...
As a greater amount of remotely sensed data becomes available, many of the applications will require the interpretation of images collected over a regular period (perhaps every day or every week) in order to identify changes associated with applications such as land-cover mapping, and environmental modelling and monitoring. Since these applications will require the transmission of significant numbers...
This paper presents a new approach to detecting features in pipe images based on a generalisation of the erosion operation. The pipe images can be segmented using support vector machine or other method. The binary image obtained in this way contains a principal connected component made up from the pipe flow lines, the pipe joints and adjoining defects. The morphological analysis allows the principal...
An efficient automatic facial expression recognition method is proposed. The method uses a set of characteristic features obtained by averaging the outputs from the Gabor filter bank with 5 frequencies and 8 different orientations, and then further reducing the dimensionality by the means of principal component analysis. The performance of the proposed system was compared with the full Gabor filter...
In this paper, we present a method for extracting salient local features from 3D models using surface curvature which has application to 3D object recognition. In the developed technique, the amount of curvature at a point is specified by a positive number known as the curvedness. This value is invariant to rotation as well as translation. A local description of the surface is generated by fitting...
Global motion estimation (GME) is an extensively used tool in a variety of video processing applications. The major challenge in this field is the presence of large foreground objects. There is a wide variety of algorithms addressing this problem. The major shortcoming of these algorithms is inconsistent performance over several video sequences. In this paper, we propose a GME approach that is fully...
All high breakdown robust estimators, at their core, include an isolated search in either the data or the parameter space. In this paper, we devise a high breakdown robust estimation technique, called fast least k-th order statistics (FLkOS) that employs the derivatives of order statistics of squared residuals to implement Newton's optimization method for its search. It is mathematically shown that...
We present an automatic method to segment the blood vessels in retinal images. Our method is based on tracking the center of the vessels using the Kalman filter. We define a linear model to track the blood vessels, suitable for both the detection of wide and thin vessels in noisy images. The estimation of the next state is computed by using gradient information, histogram of the orientations and the...
In this paper, we propose an enhanced HMM for the recognition of sigma70 promoters in E. coli. HMMs for -10 and -35 boxes have been proposed to model the positional dependency of motifs which is lost in methods based on weight matrices. We also propose to use a set of spacer states sharing the observation densities to achieve the desired spacer duration probability functions. We have conducted two...
The key issue addressed by this paper is the necessity to devise performance evaluation measures for systems that integrate multiple cues for tracking in video sequences. We propose a generic evaluation approach that can be implemented in systems that perform higher-level people tracking by integrating multiple low-level features extracted from the video data. Two new measures: video sequence accuracy...
Images of a moving object acquired by a static camera typically contain two groups of image correspondences belonging to the object in motion and the static (or nearly static) background. For objects with relatively small motion, there is little distinction between the effect of motion and the background noise. As the type of motion is also not known in advance, the fundamental matrix motion model...
We consider the task of estimating constrained parameters of geometric models which underpin an important class of computer vision problems. A typical model can often be described by two systems of equations, of which one relates image features to parameters, and the other captures internal relationships between the parameters. One way to produce constrained parameters is to first compute an unconstrained...
Aircraft tracking has applications in guided landing, automatic scoring in aerobatics and target tracking for military. Radar based tracking is expensive, gives away the position of the radar and is prone to jamming. However, vision sensors are low cost, passive and robust to jamming hence motivating their use for aircraft tracking. This paper proposes a modified KLT tracking algorithm and tests its...
An effective video surveillance system relies on detection of suspicious activities. In recent times, there has been an increasing focus on detecting anomalies in human behaviour using surveillance cameras as they provide a clue to preventing breaches in security. Human behaviour can be termed as suspicious when it is uncommon in occurrences and deviates from commonly understood behaviour within a...
In this paper, a novel methodology for facial expression rating is proposed, as the intensity of an emotion evolves from neutral to high expression. The face is modeled as a combination of sectors and their boundaries. An expression change in a face is characterised and quantified through a combination of non-rigid deformations. After elastic interpolation, this yields a geometry-based high-dimensional...
Novel methods are proposed for self-calibrating a pure-rotating camera using semidefinite programming (SDP). Key to the approach is the use of the positive-definiteness requirement for the dual image of the absolute conic (DIAC). The problem is couched within a convex optimization framework and convergence to the global optimum is guaranteed. Experiments on various data sets indicate that the proposed...
Dry Eye Syndrome is a common disease in the western world, with effects from uncomfortable itchiness to permanent damage to the ocular surface. Nevertheless, there is still no objective test that provides reliable results. We extend our method for the automated detection of dryness signs to include the breakup time (BUT), analysis of the degree of thinning of the tear film and detection of meniscus...
In this paper, we explore and examine a new novel approach to image ranking systems based on some special types of Markov chain along with new concepts of popularity and relevancy measures for image database. To be specific, this approach introduces a family of special Markov chain models in which serial correlations are explicitly involved so that we can use them as correlations among the images...
Graph-cut methods have become an intensive area of research in image processing, with applications to stereo vision, binary thresholding, classification and image de-noising amongst other areas. This paper describes novel graph-cut implementations for use in two applications: 2D optical flow and interactive object delineation. The optical flow implementation is based on recursive application of graph-cuts,...
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