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We propose a method for detecting obstacles by comparing input and reference train frontal view camera images. In the field of obstacle detection, most methods employ a machine learning approach, so they can only detect pre-trained classes, such as pedestrian, bicycle, etc. This means that obstacles of unknown classes cannot be detected. To overcome this problem, we propose a background subtraction...
This paper proposes an algorithm for fall detection using a ceiling-mounted 3D depth camera. The lying pose is separated from common daily activities by a k-NN classifier, which was trained on features expressing head-floor distance, person area and shape's major length to width. In order to distinguish between intentional lying postures and accidental falls the algorithm also employs motion between...
Based on the development of image registration, sequence registration can be done by computing the transformations between consecutive frames. To take into account the accumulated error, global registration method is usually employed as a global error minimizing approach. However, in real surveillance applications, the visible sequence and infrared sequence may be taken at different times, or from...
This paper proposes a new motion capture system to track human motion with high-speed RGB-D cameras. The proposed system uses synchronized and calibrated high-speed RGB-D cameras to simultaneously record color and depth image sequences of human motion. A new particle-based skeleton tracking process with color and depth features are adopted to track human motion without markers from high-speed RGB-D...
This paper presents Sequence Matching Across Route Traversals (SMART); a generally applicable sequence-based place recognition algorithm. SMART provides invariance to changes in illumination and vehicle speed while also providing moderate pose invariance and robustness to environmental aliasing. We evaluate SMART on vehicles travelling at highly variable speeds in two challenging environments; firstly,...
In this paper, we study the benefits of the availability of a specific form of additional information-the vertical direction (gravity) and the height of the camera, both of which can be conveniently measured using inertial sensors and a monocular video sequence for 3D urban modeling. We show that in the presence of this information, the SfM equations can be rewritten in a bilinear form. This allows...
This paper proposes a novel method for generating arbitrary stereoscopic view from multiple omni directional image sequences. Although conventional methods for arbitrary view generation with an image-based rendering approach can create binocular views, positions and directions of viewpoints for stereoscopic vision are limited to a small range. In this research, we attempt to generate arbitrary stereoscopic...
We present a complete processing chain for computing 2D occupancy grids from image sequences. A multi layer grid is introduced which serves several purposes. First the 3D points reconstructed from the images are distributed onto the underlying grid. Thereafter a virtual measurement is computed for each cell thus reducing computational complexity and rejecting potential outliers. Subsequently a height...
A common prerequisite for many vision-based driver assistance systems is the knowledge of the vehicle's own movement. In this paper we propose a novel approach for estimating the egomotion of the vehicle from a sequence of stereo images. Our method is directly based on the trifocal geometry between image triples, thus no time expensive recovery of the 3-dimensional scene structure is needed. The only...
This paper presents a new hardware-efficient method of eliminating aliasing artifacts in time direction occurring in filter results of velocity or directional filters applied to image sequences recorded by a camera. Aim is to deliver reliable input data for object detection in a driver assistance system, for example. Applications designed for mass products like these demand low production costs and...
Respiration rate is an important indicator of an individual's health. Existing respiration monitoring systems are usually contact based, and so the sensing device is attached to the subject's body. This creates discomfort to the patient and can interfere with normal breathing. This paper presents a vision based contactless method of monitoring respiration rate. The method involves image and signal...
Template matching in real-time is a fundamental issue in many applications in computer vision such as tracking, stereo vision and autonomous navigation. The goal of this paper is to present a system for automatic image sequence processing for autonomous aerial navigation research. Two main experiments were employed in this work, the first with clipping images of a geo-referenced aerial image, to simulate...
Sensors such accelerometers and displacement transducers are generally used in earthquake-simulation shake table testing to measure the induced motions. In particular the Anti-seismic Structure Laboratory at the Pontificia Universidad Cato??lica del Peru?? (PUCP) uses LVDT (linear variable differential transformer) sensors, which can achieve accurate measurements. However there are limitations in...
Detection and analysis of trajectories are effective for providing services to pedestrians in public spaces. We have proposed a method to detect moving objects from a monocular image sequence with a normal mixture model. However, the method cannot accommodate a changing number of moving objects. As described herein, to overcome this shortcoming, we proposed two algorithms for counting number of moving...
Over the last one decade there has been an increasing emphasis on driver-assistance systems for the automotive domain. In this paper we report our work on designing a camera-based surveillance system embedded in a ??smart?? car door. Such a camera is used to monitor the ambient environment outside the car - e.g., the presence of obstacles such as approaching cars or cyclists who might collide with...
In a typical video analysis framework, video sequences are decoded and reconstructed in the pixel domain before being processed for high level tasks such as classification or detection.Nevertheless, in some application scenarios, it might be of interest to complete these analysis tasks without disclosing sensitive data, e.g. the identity of people captured by surveillance cameras. In this paper we...
Omnidirectional cameras are a popular choice of visual sensors in robotics because their large field of view is well suited for motion estimation and obstacle avoidance. However their practical use is often burdened by the calibration phase that can be time consuming and require an experienced user. The contribution of this work is a simplification of calibration phase by providing a direct approach...
The sensors present in modern premium cars deliver a wealth of information. We will in this work illustrate one way of making better use of the sensor information already present in modern premium cars. More specifically, we will show how a far infrared (FIR) camera can be used to enhance the estimates of the vehicle ego-motion and indirectly the road geometry in 3D. The FIR camera is primarily intended...
Recognizing objects being manipulated in hands can provide essential information about a person's activities and have far-reaching impacts on the application of vision in everyday life. The egocentric viewpoint from a wearable camera has unique advantages in recognizing handled objects, such as having a close view and seeing objects in their natural positions. We collect a comprehensive dataset and...
This paper is concerned with the problem of capturing higher dynamic range video with a mobile device. We assume the mobile device has a standard (or low) dynamic range image sensor, and that the device is constrained by power and processing capability. To address these issues, we develop a system that captures a video sequence containing time varying exposure settings, encodes this sequence without...
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