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Acquisition of consistent multi-camera image data such as for time-slice sequences (widely known by their use as cinematic effects, e.g. in “The Matrix”) is a challenging task, especially when using low-cost image sensors. Many different steps such as camera calibration and color conformation are involved, each of which poses individual problems. We have developed a complete and extendable setup for...
Optical flow methods, such as Lucas-Kanade and Horn-Schunck algorithms, are popular in motion estimation. However, they fall short on accuracy when they are applied to blurred videos. Some people utilize hybrid camera system to get a low resolution image to suppress the blurring effect so that more accurate optical flow for blurred high resolution image can be further derived, though in most of the...
This paper deals with automatic characterization of video capture actions like scale change (zoom) or translation (traveling) in a video sequence. The overall objective is to enhance the scripted quality while capturing a video sequence by professionals or non professionals. Ultimately, the capture actions would use a predefined video template, progressively filled by the cameraman and automatically...
Pedestrian detection is one of the most important techniques for surveillance applications. This paper proposes an effective method for pedestrian detection in low-contrast images. The main characteristic of the proposed method is a two-stage moving object extraction. In the first stage, the watershed algorithm is used to extract multiple regions of moving objects. In the second stage, a novel criterion...
Super-resolution is a very well-studied topic in image enhancement. However, traditional super-resolution techniques are limited by global motion assumption and the accuracy of displacement estimation. In this paper, we are interested in the problem of constructing super-resolution images from high-speed camera sequences with the presence of moving objects. The objective of our research is finding...
Focus on the image compressing problem of unmanned aerial vehicle with high compression ratio, fixed compressing ratio and low computational complexity requirement, a low-complexity image-sequence compressing algorithm based on homography transformation was proposed. The image sequences were dynamically divided into frame-groups according the data from airborne inertial navigation systems, and the...
This paper presents an outlier removing method for improving the performance of automatic 3D reconstruction of scene using video sequences acquired with an uncalibrated camera. Firstly, the feature points in the region of interest are tracked in video sequences via KLT tracker. Secondly, we applied a vector direction analysis (VDA) strategy in our system for outlier's removal, which can efficiently...
Scene change detection is an essential step for archived films restoration. But the image quality of archived films often degrades gradually which makes false detection during shot segmentation. This paper focuses on some problems about the scene change detection in archived films. For abrupt change shot detection, the difference between histograms of block-bases adjacent frames and across frames...
The paper presents a vision based approach to facial expression recognition using commonly available hardware resources and considering very simple spatial features of the face. Face region is cropped on the image and image processing techniques are applied heuristically to local various facial feature regions. Individual feature points are detected precisely in these feature regions. Spatial rules...
Panoramic-image-based approach for representing environmental data has become a common method used by various virtual reality applications. It has many advantages over the traditional 3D modeling approaches, such as shorter generation times, faster rendering speeds, higher photorealism, and less storage needed. The drawback is however that it stores only static information of the scene. Panoramic...
This paper presents the problem of reconstructing the 3D terrain model for landing of small body spacecraft, in order to approach and land on a small body successfully. We propose an on-line terrain modeling using image sequence provided by an on-board camera. The recursive structure from motion algorithm and the orthography factorization algorithm are proposed to recover the depth maps. The application...
Manually steering the tip of a flexible endoscope to navigate through an endoluminal path relies on the physician's dexterity and experience. In this paper we present the realization of a robotic flexible endoscope steering system that uses the endoscopic images to control the tip orientation towards the direction of the lumen. Two image-based control algorithms are investigated, one is based on the...
This paper presents a method of 3D localization using image edge-points detected from binocular stereo image sequences. The proposed method calculates camera poses using visual odometry, and updates the poses by reducing the accumulated errors using landmark recognition. Landmark recognition is done based on robust and scalable image-retrieval using image edge-points with SIFT descriptors and a vocabulary...
This paper describes a topological SLAM system using a purely vision-based approach. This robot utilizes a GPU-based omnidirectional catadioptric stereovision system to perceive and plan its path in the environment. Subsequently, the omnidirectional images generated are used to incrementally build a database of image signatures based on the standard 2D Haar Wavelet decomposition. In order to maintain...
Anomaly detection in crowd scene is very important because of more concern with people safety in public place. This paper presents an approach to automatically detect abnormal behavior in crowd scene. For this purpose, instead of tracking every person, KLT corners are extracted as feature points to represent moving objects and tracked by optical flow technique to generate motion vectors, which are...
In this paper we present a novel system for real-time, six degree of freedom visual simultaneous localization and mapping using a stereo camera as the only sensor. The system makes extensive use of parallelism both on the graphics processor and through multiple CPU threads. Working together these threads achieve real-time feature tracking, visual odometry, loop detection and global map correction...
This paper presents an upper body tracking algorithm with a single monocular camera. In order to be suitable for human robot interaction, the designed method should be free to work on the moving camera platform and also can achieve real-time performance. The dimension of human posture model is extremely high, and we hereby focus on the visual extraction of head and arms. A hierarchical structure model...
This paper describes the validation process of a simulation model that have been used to explore the new possibilities of interaction when humans are guided by teams of robots that work cooperatively in urban areas. The set of experiments, which have been recorded as video sequences, show a group of people being guided by a team of three people (who play the role of the guide robots). The model used...
We present a generalization of the Koenderink-van Doorn (KvD) algorithm that allows robust monocular localization with large motion between the camera frames for a wide range of optical systems including omnidirectional systems and standard perspective cameras. The KvD algorithm estimates simultaneously ego-motion parameters, i.e. rotation, translation, and object distances in an iterative way. However...
This paper proposed a novel image stitching algorithm based on fast moving object detection and motion prediction compensation, which can avoid ghosting caused by the moving target. We estimates the global motion vector through extracting and matching SIFT features. Based on the global motion estimation, calculate the relative difference image of the overlapping region in the pair of registered images...
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