检索结果-内蒙古大学图书馆

2013 IEEE Conference on computer vision and Pattern Recognition Workshops, CVPRW 2013

作者： Ohn-Bar, Eshed Trivedi, Mohan M. Computer Vision and Robotics Research Lab University of California San Diego CA 92093-0434 United States

ISBN: (纸本)9780769549903

We propose a set of features derived from skeleton tracking of the human body and depth maps for the purpose of action recognition. The descriptors proposed are easy to implement, produce relatively small-sized feature sets, and the multi-class classification scheme is fast and suitable for real-time applications. We intuitively characterize actions using pairwise affinities between view-invariant joint angles features over the performance of an action. Additionally, a new descriptor for spatio-temporal feature extraction from color and depth images is introduced. This descriptor involves an application of a modified histogram of oriented gradients (HOG) algorithm. The application produces a feature set at every frame, and these features are collected into a 2D array which then the same algorithm is applied to again (the approach is termed HOG2). Both feature sets are evaluated in a bag-of-words scheme using a linear SVM, showing state-of-the-art results on public datasets from different domains of human-computer interaction. © 2013 IEEE.

关键词： Human computer interaction

来源：评论

学校读者我要写书评

暂无评论

The Power is in Your Hands: 3D Analysis of Hand Gestures in Naturalistic Video

The Power is in Your Hands: 3D Analysis of Hand Gestures in ...

引用

IEEE Conference on computer vision and Pattern Recognition Workshops

作者： Eshed Ohn-Bar Mohan M. Trivedi Computer Vision and Robotics Research Lab University of California

ISBN: (纸本)9781479909940

We study natural human activity under difficult settings of cluttered background, volatile illumination, and frequent occlusion. To that end, a two-stage method for hand and hand-object interaction detection is developed. First, activity proposals are generated from multiple sub-regions in the scene. Then, these are integrated using a second-stage classifier. We study a set of descriptors for detection and activity recognition in terms of performance and speed. With the overarching goal of reducing 'lab setting bias', a case study is introduced with a publicly available annotated RGB and depth dataset. The dataset was captured using a Kinect under real-world driving settings. The approach is motivated by studying actions-as well as semantic elements in the scene and the driver's interaction with them-which may be used to infer driver inattentiveness. The proposed framework significantly outperforms a state-of-the-art baseline on our dataset for hand detection.

关键词： Hand Dataset three dimensional analysis game player Gestures scaffolding method Human Activities distractability Drivers Videotapes

来源：评论

学校读者我要写书评

暂无评论

Radiometric calibration by transform invariant low-rank structure

Radiometric calibration by transform invariant low-rank stru...

引用

作者： Lee, Joon-Young Shi, Boxin Matsushita, Yasuyuki Kweon, In-So Ikeuchi, Katsushi Robotics and Computer Vision Lab KAIST Korea Republic of University of Tokyo Japan Microsoft Research Asia China

ISBN: (纸本)9781457703942

We present a robust radiometric calibration method that capitalizes on the transform invariant low-rank structure of sensor irradiances recorded from a static scene with different exposure times. We formulate the radiometric calibration problem as a rank minimization problem. Unlike previous approaches, our method naturally avoids over-fitting problem;therefore, it is robust against biased distribution of the input data, which is common in practice. When the exposure times are completely unknown, the proposed method can robustly estimate the response function up to an exponential ambiguity. The method is evaluated using both simulation and real-world datasets and shows a superior performance than previous approaches. © 2011 IEEE.

关键词： Radiometry

来源：评论

学校读者我要写书评

暂无评论

Retinal vessel tortuosity evaluation via circular hough transform

Retinal vessel tortuosity evaluation via circular hough tran...

引用

2011 18th Iranian Conference of Biomedical Engineering, ICBME 2011

作者： Ghadiri, Farnoosh Pourreza, Hamidreza Banaee, Touka Delgir, Morteza Computer Engineering Department Machine Vision Lab Ferdowsi University Mashhad Iran Ophthalmic Research Center Khatam-Al-Anbia Hospital Medical Science University Mashhad Iran Computer Science Department Robotics Lab Northeastern University United States

ISBN: (纸本)9781467310055

Retinal vessel tortuosity has shown to be significantly associated with cardiovascular diseases such as hypertension and diabetes. Despite importance of this field a few techniques have been proposed yet. All previous methods rely on a vessel extraction phase, which its accuracy affects final output and also time consuming. Nobility of presented algorithm is to introduce a method for evaluating retinal vessel tortuosity without any explicit vessel detection. We use the Circular Hough Transform (CHT) based on gradient field of the retinal image. Each vessel curve is detected as a semi-circle by Hough transform and tortuosity of the curve is determined with the help of accumulated value of circle center and its radius. As there are no any specific database for tortuosity evaluation, the algorithm was tasted on database consisting of 40 images, mixture of DRIVE database and images from Khatam-Al-Anbia Hospital consisting of 40 retinal images, of which 20 were tortuous and 20 were non-tortuous. The proposed algorithm can achieve classification rate of 92% along with less computation time in compare of previous methods. © 2011 IEEE.

关键词： Database systems

来源：评论

学校读者我要写书评

暂无评论

Radiometric Calibration by Transform Invariant Low-rank Structure

Radiometric Calibration by Transform Invariant Low-rank Stru...

引用

IEEE Conference on computer vision and Pattern Recognition

作者： Joon-Young Lee Boxin Shi Yasuyuki Matsushita In-So Kweon Katsushi Ikeuchi Robotics and Computer Vision Lab KAIST The University of Tokyo Microsoft Research Asia

ISBN: (纸本)9781457703942

关键词： exposure time incoming data Radiation Response function Invariant Transform CALIBRATION METHODS

来源：评论

学校读者我要写书评

暂无评论

Attention estimation by simultaneous observation of viewer and view

Attention estimation by simultaneous observation of viewer a...

引用

2010 IEEE computer Society Conference on computer vision and Pattern Recognition - Workshops, CVPRW 2010

作者： Doshi, Anup Trivedi, Mohan M. Computer Vision and Robotics Research Lab University of California San Diego CA 92093-0434 United States

ISBN: (纸本)9781424470297

We introduce a new approach to analyzing the attentive state of a human subject, given cameras focused on the subject and their environment. In particular, the task of analyzing the focus of attention of a human driver is of primary concern. Up to 80% of automobile crashes are related to driver inattention;thus it is important for an Intelligent Driver Assistance System (IDAS) to be aware of the driver state. We present a new Bayesian paradigm for estimating human attention specifically addressing the problems arising in dynamic situations. The model incorporates vision-based gaze estimation, "top-down"-and "bottomup"-based visual saliency maps, and cognitive considerations such as inhibition of return and center bias that affect the relationship between gaze and attention. Results demonstrate the validity on real driving data, showing quantitative improvements over systems using only gaze or only saliency, and elucidate the value of such a model for any human-machine interface. © 2010 IEEE.

关键词： Accidents

来源：评论

学校读者我要写书评

暂无评论

Pushing the envelope of modern methods for bundle adjustment

Pushing the envelope of modern methods for bundle adjustment

引用

Conference on computer vision and Pattern Recognition (CVPR)

作者： Yekeun Jeong David Nister Drew Steedly Richard Szeliski In-So Kweon Robotics and Computer Vision Lab. KAIST Microsoft Research South Korea Robotics and Computer Vision Lab. KAIST Microsoft Research Robotics and Computer Vision Lab. KAIST Microsoft Research USA

In this paper, we present results and experiments with several methods for bundle adjustment, producing the fastest bundle adjuster ever published. The fastest methods work with the well known reduced camera system and handle the block-sparse pattern arising in the reduced camera system in a natural way. Adapting to the naturally arising block-sparsity allows the use of BLAS3, efficient memory handling, fast variable ordering, and customized sparse solving all at the same time. We present two methods, one using exact minimum degree ordering and block-based LDL solving, and one using block-based preconditioned conjugate gradient, both on the reduced camera system. We show experimentally that the adaptation to the natural block sparsity allows both these methods to perform better than previous ones. Further speed improvements are achieved by the novel use of embedded point iterations. The embedded point iterations take place inside each camera update step, yielding a higher cost decrease from each camera update step. This is especially true for points projecting far out on the flatter region of the robustifier.

关键词： Cameras Robot vision systems Large-scale systems computer vision Costs Convergence Character generation Robustness Frequency conversion Humans

来源：评论

学校读者我要写书评

暂无评论

Attention estimation by simultaneous observation of viewer and view

Attention estimation by simultaneous observation of viewer a...

引用

IEEE computer Society Conference on computer vision and Pattern Recognition Workshops (CVPRW)

作者： Anup Doshi Mohan M. Trivedi Computer Vision and Robotics Research Lab University of California San Diego La Jolla CA USA

We introduce a new approach to analyzing the attentive state of a human subject, given cameras focused on the subject and their environment. In particular, the task of analyzing the focus of attention of a human driver is of primary concern. Up to 80% of automobile crashes are related to driver inattention; thus it is important for an Intelligent Driver Assistance System (IDAS) to be aware of the driver state. We present a new Bayesian paradigm for estimating human attention specifically addressing the problems arising in dynamic situations. The model incorporates vision-based gaze estimation, “top-down”- and “bottom-up”-based visual saliency maps, and cognitive considerations such as inhibition of return and center bias that affect the relationship between gaze and attention. Results demonstrate the validity on real driving data, showing quantitative improvements over systems using only gaze or only saliency, and elucidate the value of such a model for any human-machine interface.

关键词： Humans Layout State estimation Bayesian methods Vehicle dynamics Robot vision systems Man machine systems Probability distribution Computational modeling Observers

来源：评论

学校读者我要写书评

暂无评论

MULTI-CAMERA POSITIONING FOR AUTOMATED TRACKING SYSTEMS IN DYNAMIC ENVIRONMENTS

引用

International Journal of Information Acquisition 2010年第3期7卷 225-242页

作者： YI YAO CHUNG-HAO CHEN BESMA ABIDI DAVID PAGE ANDREAS KOSCHAN MONGI ABIDI Visualization and Computer Vision Lab GE Global Research USA Department of Mathematics and Computer Science North Carolina Central University USA Imaging Robotics and Intelligent Systems Lab University of Tennessee Knoxville USA

Most existing camera placement algorithms focus on coverage and/or visibility analysis, which ensures that the object of interest is visible in the camera's field of view (FOV). According to recent literature, handoff safety margin is introduced to sensor planning so that sufficient overlapped FOVs among adjacent cameras are reserved for successful and smooth target transition. In this paper, we investigate the sensor planning problem when considering the dynamic interactions between moving targets and observing cameras. The probability of camera overload is explored to model the aforementioned interactions. The introduction of the probability of camera overload also considers the limitation that a given camera can simultaneously monitor or track a fixed number of targets and incorporates the target's dynamics into sensor planning. The resulting camera placement not only achieves the optimal balance between coverage and handoff success rate but also maintains the optimal balance in environments with various target densities. The proposed camera placement method is compared with a reference algorithm by Erdem and Sclaroff. Consistently improved handoff success rate is illustrated via experiments using typical office floor plans with various target densities.

关键词： Sensor planning visual surveillance multiple camera systems camera handoff

来源：评论

学校读者我要写书评

暂无评论

Mobile robot localization using panoramic vision and combinations of feature region detectors

Mobile robot localization using panoramic vision and combina...

引用

IEEE International Conference on robotics and Automation (ICRA)

作者： Arnau Ramisa Adriana Tapus Ramon Lopez de Mantaras Ricardo Toledo Artificial Intelligence Research Institute Spain Robotics Research Lab Interaction Lab Department of Computer Science University of Southern California Los Angeles USA UAB Campus Computer Vision Center Spain

This paper presents a vision-based approach for mobile robot localization. The environmental model is topological. The new approach uses a constellation of different types of affine covariant regions to characterize a place. This type of representation permits a reliable and distinctive environment modeling. The performance of the proposed approach is evaluated using a database of panoramic images from different rooms. Additionally, we compare different combinations of complementary feature region detectors to find the one that achieves the best results. Our experimental results show promising results for this new localization method. Additionally, similarly to what happens with single detectors, different combinations exhibit different strengths and weaknesses depending on the situation, suggesting that a context-aware method to combine the different detectors would improve the localization results.

关键词： Mobile robots computer vision Detectors Robot kinematics Robot localization Feature extraction Fingerprint recognition robotics and automation USA Councils Image databases

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：