413 research outputs found
Object Tracking in Distributed Video Networks Using Multi-Dimentional Signatures
From being an expensive toy in the hands of governmental agencies, computers have evolved a long way from the huge vacuum tube-based machines to today\u27s small but more than thousand times powerful personal computers. Computers have long been investigated as the foundation for an artificial vision system. The computer vision discipline has seen a rapid development over the past few decades from rudimentary motion detection systems to complex modekbased object motion analyzing algorithms. Our work is one such improvement over previous algorithms developed for the purpose of object motion analysis in video feeds. Our work is based on the principle of multi-dimensional object signatures. Object signatures are constructed from individual attributes extracted through video processing. While past work has proceeded on similar lines, the lack of a comprehensive object definition model severely restricts the application of such algorithms to controlled situations. In conditions with varying external factors, such algorithms perform less efficiently due to inherent assumptions of constancy of attribute values. Our approach assumes a variable environment where the attribute values recorded of an object are deemed prone to variability. The variations in the accuracy in object attribute values has been addressed by incorporating weights for each attribute that vary according to local conditions at a sensor location. This ensures that attribute values with higher accuracy can be accorded more credibility in the object matching process. Variations in attribute values (such as surface color of the object) were also addressed by means of applying error corrections such as shadow elimination from the detected object profile. Experiments were conducted to verify our hypothesis. The results established the validity of our approach as higher matching accuracy was obtained with our multi-dimensional approach than with a single-attribute based comparison
Occlusion handling in multiple people tracking
Object tracking with occlusion handling is a challenging problem in automated video surveillance. Occlusion handling and tracking have always been considered as separate modules. We have proposed an automated video surveillance system, which automatically detects occlusions and perform occlusion handling, while the tracker continues to track resulting separated objects. A new approach based on sub-blobbing is presented for tracking objects accurately and steadily, when the target encounters occlusion in video sequences. We have used a feature-based framework for tracking, which involves feature extraction and feature matching
Comprehensive Survey and Analysis of Techniques, Advancements, and Challenges in Video-Based Traffic Surveillance Systems
The challenges inherent in video surveillance are compounded by a several factors, like dynamic lighting conditions, the coordination of object matching, diverse environmental scenarios, the tracking of heterogeneous objects, and coping with fluctuations in object poses, occlusions, and motion blur. This research endeavor aims to undertake a rigorous and in-depth analysis of deep learning- oriented models utilized for object identification and tracking. Emphasizing the development of effective model design methodologies, this study intends to furnish a exhaustive and in-depth analysis of object tracking and identification models within the specific domain of video surveillance
์ค์๊ฐ ์์จ์ฃผํ ์ธ์ง ์์คํ ์ ์ํ ์ ๊ฒฝ ๋คํธ์ํฌ์ ๊ตฐ์งํ ๊ธฐ๋ฐ ๋ฏธํ์ต ๋ฌผ์ฒด ๊ฐ์ง๊ธฐ ํตํฉ
ํ์๋
ผ๋ฌธ (๋ฐ์ฌ) -- ์์ธ๋ํ๊ต ๋ํ์ : ๊ณต๊ณผ๋ํ ๊ธฐ๊ณํญ๊ณต๊ณตํ๋ถ, 2020. 8. ์ด๊ฒฝ์.์ต๊ทผ ๋ช ๋
๊ฐ, ์ผ์ ๊ธฐ์ ์ ๋ฐ์ ๊ณผ ์ปดํจํฐ ๊ณตํ ๋ถ์ผ์ ์ฑ๊ณผ๋ค๋ก ์ธํ์ฌ ์์จ์ฃผํ ์ฐ๊ตฌ๊ฐ ๋์ฑ ํ๋ฐํด์ง๊ณ ์๋ค. ์์จ์ฃผํ ์์คํ
์ ์์ด์ ์ฐจ๋ ์ฃผ๋ณ ํ๊ฒฝ์ ์ธ์ํ๋ ๊ฒ์ ์์ ๋ฐ ์ ๋ขฐ์ฑ ์๋ ์ฃผํ์ ํ๊ธฐ ์ํด ํ์ํ ๊ฐ์ฅ ์ค์ํ ๊ธฐ๋ฅ์ด๋ค. ์์จ์ฃผํ ์์คํ
์ ํฌ๊ฒ ์ธ์ง, ํ๋จ, ์ ์ด๋ก ๊ตฌ์ฑ๋์ด ์๋๋ฐ, ์ธ์ง ๋ชจ๋์ ์์จ์ฃผํ ์ฐจ๋์ด ๊ฒฝ๋ก๋ฅผ ์ค์ ํ๊ณ ํ๋จ, ์ ์ด๋ฅผ ํจ์ ์์ ์ฃผ๋ณ ๋ฌผ์ฒด์ ์์น์ ์์ง์์ ํ์
ํด์ผํ๊ธฐ ๋๋ฌธ์ ์ค์ํ ์ ๋ณด๋ฅผ ์ ๊ณตํ๋ค.
์์จ์ฃผํ ์ธ์ง ๋ชจ๋์ ์ฃผํ ํ๊ฒฝ์ ํ์
ํ๊ธฐ ์ํด ๋ค์ํ ์ผ์๊ฐ ์ฌ์ฉ๋๋ค. ๊ทธ ์ค์์๋ LiDAR์ ํ์ฌ ๋ง์ ์์จ์ฃผํ ์ฐ๊ตฌ์์ ๊ฐ์ฅ ๋๋ฆฌ ์ฌ์ฉ๋๋ ์ผ์ ์ค ํ๋๋ก, ๋ฌผ์ฒด์ ๊ฑฐ๋ฆฌ ์ ๋ณด ํ๋์ ์์ด์ ๋งค์ฐ ์ ์ฉํ๋ค. ๋ณธ ๋
ผ๋ฌธ์์๋ LiDAR์์ ์์ฑ๋๋ ํฌ์ธํธ ํด๋ผ์ฐ๋ raw ๋ฐ์ดํฐ๋ฅผ ํ์ฉํ์ฌ ์ฅ์ ๋ฌผ์ 3D ์ ๋ณด๋ฅผ ํ์
ํ๊ณ ์ด๋ค์ ์ถ์ ํ๋ ์ธ์ง ๋ชจ๋์ ์ ์ํ๋ค. ์ธ์ง ๋ชจ๋์ ์ ์ฒด ํ๋ ์์ํฌ๋ ํฌ๊ฒ ์ธ ๋จ๊ณ๋ก ๊ตฌ์ฑ๋๋ค. 1๋จ๊ณ๋ ๋น์ง๋ฉด ํฌ์ธํธ ์ถ์ ์ ์ํ ๋ง์คํฌ ์์ฑ, 2๋จ๊ณ๋ ํน์ง ์ถ์ถ ๋ฐ ์ฅ์ ๋ฌผ ๊ฐ์ง, 3๋จ๊ณ๋ ์ฅ์ ๋ฌผ ์ถ์ ์ผ๋ก ๊ตฌ์ฑ๋๋ค. ํ์ฌ ๋๋ถ๋ถ์ ์ ๊ฒฝ๋ง ๊ธฐ๋ฐ์ ๋ฌผ์ฒด ํ์ง๊ธฐ๋ ์ง๋ํ์ต์ ํตํด ํ์ต๋๋ค. ๊ทธ๋ฌ๋ ์ง๋ํ์ต ๊ธฐ๋ฐ ์ฅ์ ๋ฌผ ํ์ง๊ธฐ๋ ํ์ตํ ์ฅ์ ๋ฌผ์ ์ฐพ๋๋ค๋ ๋ฐฉ๋ฒ๋ก ์ ํ๊ณ๋ฅผ ์ง๋๊ณ ์๋ค. ๊ทธ๋ฌ๋ ์ค์ ์ฃผํ์ํฉ์์๋ ๋ฏธ์ฒ ํ์ตํ์ง ๋ชปํ ๋ฌผ์ฒด๋ฅผ ๋ง์ฃผํ๊ฑฐ๋ ์ฌ์ง์ด ํ์ตํ ๋ฌผ์ฒด๋ ๋์น ์ ์๋ค. ์ธ์ง ๋ชจ๋์ 1๋จ๊ณ์์ ์ด๋ฌํ ์ง๋ํ์ต์ ๋ฐฉ๋ฒ๋ก ์ ํ๊ณ์ ๋์ฒํ๊ธฐ ์ํด ํฌ์ธํธ ํด๋ผ์ฐ๋๋ฅผ ์ผ์ ํ ๊ฐ๊ฒฉ์ผ๋ก ๊ตฌ์ฑ๋ 3D ๋ณต์
(voxel)๋ก ๋ถํ ํ๊ณ , ์ด๋ก๋ถํฐ ๋น์ ์ง์ ๋ค์ ์ถ์ถํ ๋ค ๋ฏธ์ง์ ๋ฌผ์ฒด(Unknown object)๋ฅผ ํ์งํ๋ค. 2๋จ๊ณ์์๋ ๊ฐ ๋ณต์
์ ํน์ฑ์ ์ถ์ถ ๋ฐ ํ์ตํ๊ณ ๋คํธ์ํฌ๋ฅผ ํ์ต์ํด์ผ๋ก์จ ๊ฐ์ฒด ๊ฐ์ง๊ธฐ๋ฅผ ๊ตฌ์ฑํ๋ค. ๋ง์ง๋ง 3๋จ๊ณ์์๋ ์นผ๋ง ํํฐ์ ํ๊ฐ๋ฆฌ์ ์๊ณ ๋ฆฌ์ฆ์ ํ์ฉํ ๋ค์ค ๊ฐ์ฒด ํ์ง๊ธฐ๋ฅผ ์ ์ํ๋ค. ์ด๋ ๊ฒ ๊ตฌ์ฑ๋ ์ธ์ง ๋ชจ๋์ ๋น์ง๋ฉด ์ ๋ค์ ์ถ์ถํ์ฌ ํ์ตํ์ง ์์ ๋ฌผ์ฒด์ ๋ํด์๋ ๋ฏธ์ง์ ๋ฌผ์ฒด(Unknown object)๋ก ๊ฐ์งํ์ฌ ์ค์๊ฐ์ผ๋ก ์ฅ์ ๋ฌผ ํ์ง๊ธฐ๋ฅผ ๋ณด์ํ๋ค. ์ต๊ทผ ๋ผ์ด๋ค๋ฅผ ํ์ฉํ ์์จ์ฃผํ ์ฉ ๊ฐ์ฒด ํ์ง๊ธฐ์ ๋ํ ์ฐ๊ตฌ๊ฐ ํ๋ฐํ ์งํ๋๊ณ ์์ผ๋ ๋๋ถ๋ถ์ ์ฐ๊ตฌ๋ค์ ๋จ์ผ ํ๋ ์์ ๋ฌผ์ฒด ์ธ์์ ๋ํด ์ง์คํ์ฌ ์ ํ๋๋ฅผ ์ฌ๋ฆฌ๋ ๋ฐ ์ง์คํ๊ณ ์๋ค. ๊ทธ๋ฌ๋ ์ด๋ฌํ ์ฐ๊ตฌ๋ ๊ฐ์ง ์ค์๋์ ํ๋ ์ ๊ฐ์ ๊ฐ์ง ์ฐ์์ฑ ๋ฑ์ ๋ํ ๊ณ ๋ ค๊ฐ ๋์ด์์ง ์๋ค๋ ํ๊ณ์ ์ด ์กด์ฌํ๋ค. ๋ณธ ๋
ผ๋ฌธ์์๋ ์ค์๊ฐ ์ฑ๋ฅ์ ์ป๊ธฐ ์ํด ์ด๋ฌํ ๋ถ๋ถ์ ๊ณ ๋ คํ ์ฑ๋ฅ ์ง์๋ฅผ ์ ์ํ๊ณ , ์ค์ฐจ ์คํ์ ํตํด ์ ์ํ ์ธ์ง ๋ชจ๋์ ํ
์คํธ, ์ ์ํ ์ฑ๋ฅ ์ง์๋ฅผ ํตํด ํ๊ฐํ์๋ค.In recent few years, the interest in automotive researches on autonomous driving system has been grown up due to advances in sensing technologies and computer science. In the development of autonomous driving system, knowledge about the subject vehicles surroundings is the most essential function for safe and reliable driving. When it comes to making decisions and planning driving scenarios, to know the location and movements of surrounding objects and to distinguish whether an object is a car or pedestrian give valuable information to the autonomous driving system. In the autonomous driving system, various sensors are used to understand the surrounding environment. Since LiDAR gives the distance information of surround objects,
it has been the one of the most commonly used sensors in the development of perception system.
Despite achievement of the deep neural network research field, its application and research trends on 3D object detection using LiDAR point cloud tend to pursue higher accuracy without considering a practical application. A deep neural-network-based perception module heavily depends on the training dataset, but it is impossible to cover all the possibilities and corner cases. To apply the perception module in actual driving, it needs to detect unknown objects and unlearned objects, which may face on the road. To cope with these
problems, in this dissertation, a perception module using LiDAR point cloud is proposed, and its performance is validated via real vehicle test. The whole framework is composed of three stages : stage-1 for the ground estimation playing as a mask for point filtering which are considered as non-ground and stage-2 for feature extraction and object detection, and stage-3 for object tracking. In the first stage, to cope with the methodological limit of supervised learning that only finds learned object, we divide a point cloud into equally spaced 3D voxels the point cloud and extract non-ground points and cluster the points to detect unknown objects. In the second stage, the voxelization is utilized to learn the characteristics of point clouds organized in vertical columns. The trained network can distinguish the object through the extracted features from point clouds. In non-maximum suppression process, we sort the predictions according to IoU between prediction and polygon to select a prediction close to the actual heading angle of the object. The last stage presents a 3D multiple object tracking solution. Through Kalman filter, the learned and unlearned objects next movement is predicted and this prediction updated by measurement detection. Through this process, the proposed object detector complements the detector based on supervised learning by detecting the unlearned object as an unknown object through non-ground point extraction. Recent researches on object detection for autonomous driving have been actively conducted, but recent works tend to focus more on the recognition of the objects at every single frame and developing accurate system. To obtain a real-time performance, this paper focuses on more practical aspects by propose a performance index considering detection priority and detection continuity. The performance of the proposed algorithm has been investigated via real-time vehicle test.Chapter 1 Introduction 1
1.1. Background and Motivation 1
1.2. Overview and Previous Researches 4
1.3. Thesis Objectives 12
1.4. Thesis Outline 14
Chapter 2 Overview of a Perception in Automated Driving 15
Chapter 3 Object Detector 18
3.1. Voxelization & Feature Extraction 22
3.2. Backbone Network 25
3.3. Detection Head & Loss Function Design 28
3.4. Loss Function Design 30
3.5. Data Augmentation 33
3.6. Post Process 39
Chapter 4 Non-Ground Point Clustering 42
4.1. Previous Researches for Ground Removal 44
4.2. Non-Ground Estimation using Voxelization 45
4.3. Non-ground Object Segmentation 50
4.3.1. Object Clustering 52
4.3.2. Bounding Polygon 55
Chapter 5 . Object Tracking 57
5.1. State Prediction and Update 58
5.2. Data Matching Association 60
Chapter 6 Test result for KITTI dataset 62
6.1. Quantitative Analysis 62
6.2. Qualitative Analysis 72
6.3. Additional Training 76
6.3.1. Additional data acquisition 78
6.3.2. Qualitative Analysis 81
Chapter 7 Performance Evaluation 85
7.1. Current Evaluation Metrics 85
7.2. Limitations of Evaluation Metrics 87
7.2.1. Detection Continuity 87
7.2.2. Detection Priority 89
7.3. Criteria for Performance Index 91
Chapter 8 Vehicle Tests based Performance Evaluation 95
8.1. Configuration of Vehicle Tests 95
8.2. Qualitative Analysis 100
8.3. Quantitative Analysis 105
Chapter 9 Conclusions and Future Works 107
Bibliography 109
๊ตญ๋ฌธ ์ด๋ก 114Docto
Classifying tracked objects in far-field video surveillance
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.Includes bibliographical references (p. 67-70).Automated visual perception of the real world by computers requires classification of observed physical objects into semantically meaningful categories (such as 'car' or 'person'). We propose a partially-supervised learning framework for classification of moving objects-mostly vehicles and pedestrians-that are detected and tracked in a variety of far-field video sequences, captured by a static, uncalibrated camera. We introduce the use of scene-specific context features (such as image-position of objects) to improve classification performance in any given scene. At the same time, we design a scene-invariant object classifier, along with an algorithm to adapt this classifier to a new scene. Scene-specific context information is extracted through passive observation of unlabelled data. Experimental results are demonstrated in the context of outdoor visual surveillance of a wide variety of scenes.by Biswajit Bose.S.M
Applications of ISES for vegetation and land use
Remote sensing relative to applications involving vegetation cover and land use is reviewed to consider the potential benefits to the Earth Observing System (Eos) of a proposed Information Sciences Experiment System (ISES). The ISES concept has been proposed as an onboard experiment and computational resource to support advanced experiments and demonstrations in the information and earth sciences. Embedded in the concept is potential for relieving the data glut problem, enhancing capabilities to meet real-time needs of data users and in-situ researchers, and introducing emerging technology to Eos as the technology matures. These potential benefits are examined in the context of state-of-the-art research activities in image/data processing and management
Alignment control using visual servoing and mobilenet single-shot multi-box detection (SSD): a review
The concept is highly critical for robotic technologies that rely on visual feedback. In this context, robot systems tend to be unresponsive due to reliance on pre-programmed trajectory and path, meaning the occurrence of a change in the environment or the absence of an object. This review paper aims to provide comprehensive studies on the recent application of visual servoing and DNN. PBVS and Mobilenet-SSD were chosen algorithms for alignment control of the film handler mechanism of the portable x-ray system. It also discussed the theoretical framework features extraction and description, visual servoing, and Mobilenet-SSD. Likewise, the latest applications of visual servoing and DNN was summarized, including the comparison of Mobilenet-SSD with other sophisticated models. As a result of a previous study presented, visual servoing and MobileNet-SSD provide reliable tools and models for manipulating robotics systems, including where occlusion is present. Furthermore, effective alignment control relies significantly on visual servoing and deep neural reliability, shaped by different parameters such as the type of visual servoing, feature extraction and description, and DNNs used to construct a robust state estimator. Therefore, visual servoing and MobileNet-SSD are parameterized concepts that require enhanced optimization to achieve a specific purpose with distinct tools
Development of bent-up triangular tab shear transfer (BTTST) enhancement in cold-formed steel (CFS)-concrete composite beams
Cold-formed steel (CFS) sections, have been recognised as an important
contributor to environmentally responsible and sustainable structures in developed
countries, and CFS framing is considered as a sustainable 'green' construction material
for low rise residential and commercial buildings. However, there is still lacking of data
and information on the behaviour and performance of CFS beam in composite
construction. The use of CFS has been limited to structural roof trusses and a host of nonstructural applications. One of the limiting features of CFS is the thinness of its section
(usually between 1.2 and 3.2 mm thick) that makes it susceptible to torsional,
distortional, lateral-torsional, lateral-distortional and local buckling. Hence, a reasonable
solution is resorting to a composite construction of structural CFS section and reinforced
concrete deck slab, which minimises the distance from the neutral-axis to the top of the
deck and reduces the compressive bending stress in the CFS sections. Also, by arranging
two CFS channel sections back-to-back restores symmetricity and suppresses lateraltorsional and to a lesser extent, lateral-distortional buckling. The two-fold advantages
promised by the system, promote the use of CFS sections in a wider range of structural
applications. An efficient and innovative floor system of built-up CFS sections acting
compositely with a concrete deck slab was developed to provide an alternative composite
system for floors and roofs in buildings. The system, called Precast Cold-Formed SteelConcrete Composite System, is designed to rely on composite actions between the CFS
sections and a reinforced concrete deck where shear forces between them are effectively
transmitted via another innovative shear transfer enhancement mechanism called a bentup triangular tab shear transfer (BTTST). The study mainly comprises two major
components, i.e. experimental and theoretical work. Experimental work involved smallscale and large-scale testing of laboratory tests. Sixty eight push-out test specimens and
fifteen large-scale CFS-concrete composite beams specimens were tested in this program.
In the small-scale test, a push-out test was carried out to determine the strength and
behaviour of the shear transfer enhancement between the CFS and concrete. Four major
parameters were studied, which include compressive strength of concrete, CFS strength,
dimensions (size and angle) of BTTST and CFS thickness. The results from push-out test
were used to develop an expression in order to predict the shear capacity of innovative
shear transfer enhancement mechanism, BTTST in CFS-concrete composite beams. The
value of shear capacity was used to calculate the theoretical moment capacity of CFSconcrete composite beams. The theoretical moment capacities were used to validate the
large-scale test results. The large-scale test specimens were tested by using four-point
load bending test. The results in push-out tests show that specimens employed with
BTTST achieved higher shear capacities compared to those that rely only on a natural
bond between cold-formed steel and concrete and specimens with Lakkavalli and Liu
bent-up tab (LYLB). Load capacities for push-out test specimens with BTTST are
ii
relatively higher as compared to the equivalent control specimen, i.e. by 91% to 135%.
When compared to LYLB specimens the increment is 12% to 16%. In addition, shear
capacities of BTTST also increase with the increase in dimensions (size and angle) of
BTTST, thickness of CFS and concrete compressive strength. An equation was
developed to determine the shear capacity of BTTST and the value is in good agreement
with the observed test values. The average absolute difference between the test values
and predicted values was found to be 8.07%. The average arithmetic mean of the
test/predicted ratio (n) of this equation is 0.9954. The standard deviation (a) and the
coefficient of variation (CV) for the proposed equation were 0.09682 and 9.7%,
respectively. The proposed equation is recommended for the design of BTTST in CFSconcrete composite beams. In large-scale testing, specimens employed with BTTST
increased the strength capacities and reduced the deflection of the specimens. The
moment capacities, MU ) e X p for all specimens are above Mu>theory and show good agreement
with the calculated ratio (>1.00). It is also found that, strength capacities of CFS-concrete
composite beams also increase with the increase in dimensions (size and angle) of
BTTST, thickness of CFS and concrete compressive strength and a CFS-concrete
composite beam are practically designed with partial shear connection for equal moment
capacity by reducing number of BTTST. It is concluded that the proposed BTTST shear
transfer enhancement in CFS-concrete composite beams has sufficient strength and is
also feasible. Finally, a standard table of characteristic resistance, P t a b of BTTST in
normal weight concrete, was also developed to simplify the design calculation of CFSconcrete composite beams
Scalable and adaptable tracking of humans in multiple camera systems
The aim of this thesis is to track objects on a network of cameras both within [intra) and across (inter) cameras. The algorithms must be adaptable to change and are learnt in a scalable approach. Uncalibrated cameras are used that are patially separated, and therefore tracking must be able to cope with object oclusions, illuminations changes, and gaps between cameras.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Videogames: the new GIS?
Videogames and GIS have more in common than might be expected. Indeed, it is suggested that videogame technology may not only be considered as a kind of GIS, but that in several important respects its world modelling capabilities out-perform those of most GIS. This chapter examines some of the key differences between videogames and GIS, explores a number of perhaps-surprising similarities between their technologies, and considers which ideas might profitably be borrowed from videogames to improve GIS functionality and usability
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