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Algorithm Research on Moving Vehicles Detection

Wei Zhan, Xiaolong Ji
2011 Procedia Engineering  
Experiment shows that the algorithm framework is practicable.  ...  Traditional method of moving vehicles detection from video is image subtraction which is apt to be affected by brightness changing, in this paper a kind of moving vehicles detection algorithm based on  ...  The basic idea of the pyramidal optical flow is to construct image pyramids which resolution reduce gradually from bottom to top of the pyramid, that is to say, image's resolution is highest on the bottom  ... 
doi:10.1016/j.proeng.2011.08.1017 fatcat:hp3np6tvtbcczcgn4ssw7bxlqe

Detecting salient motion by accumulating directionally-consistent flow

L. Wixson
2000 IEEE Transactions on Pattern Analysis and Machine Intelligence  
We propose an algorithm for detecting this salient motion that is based on intermediate-stage vision integration of optical flow.  ...  ., a person or vehicle traveling with a sense of direction through a scene) as opposed to other distracting motions (e.g., the scintillation of specularities on water, the oscillation of vegetation in  ...  The constant k is the pixel distance by which the two flow vectors can differ. Generally, when flow vectors are incorrect this distance will be large, so in practice k Q produces adequate checking.  ... 
doi:10.1109/34.868680 fatcat:l6kvz46kojb6dougwttxy6tr6q

Detecting salient motion by accumulating directionally-consistent flow

L. Wixson, M. Hansen
1999 Proceedings of the Seventh IEEE International Conference on Computer Vision  
We propose an algorithm for detecting this salient motion that is based on intermediate-stage vision integration of optical flow.  ...  ., a person or vehicle traveling with a sense of direction through a scene) as opposed to other distracting motions (e.g., the scintillation of specularities on water, the oscillation of vegetation in  ...  The constant k is the pixel distance by which the two flow vectors can differ. Generally, when flow vectors are incorrect this distance will be large, so in practice k Q produces adequate checking.  ... 
doi:10.1109/iccv.1999.790303 dblp:conf/iccv/WixsonH99 fatcat:ljhehu35yne5nedoqe5lunlfwa

Adaptive Detection of a Moving Target Undergoing Illumination Changes against a Dynamic Background

Mu Lu, Yang Gao, Ming Zhu
2016 Journal of the Optical Society of Korea  
changes on optical-flow estimates.  ...  A detection algorithm, based on the combined local-global (CLG) optical-flow model and Gaussian pyramid for a moving target appearing against a dynamic background, can compensate for the inadaptability  ...  Deducing from these results, the optical-flow of the top layer of the Gaussian pyramid is For low layers of the Gaussian pyramid, with fewer pixel points in an image, the optical-flow precision can be  ... 
doi:10.3807/josk.2016.20.6.745 fatcat:jekoicj43rglxmltpqkddt57mu

Sensitivity of PCA for traffic anomaly detection

Haakon Ringberg, Augustin Soule, Jennifer Rexford, Christophe Diot
2007 Proceedings of the 2007 ACM SIGMETRICS international conference on Measurement and modeling of computer systems - SIGMETRICS '07  
In recent years, network-wide anomaly detection based on Principal Component Analysis (PCA) has emerged as a powerful method for detecting a wide variety of anomalies.  ...  Our study identifies and evaluates four main challenges of using PCA to detect traffic anomalies: (i) the false positive rate is very sensitive to small differences in the number of principal components  ...  ACKNOWLEDGMENTS The authors would like to thank Mark Crovella and Anukool Lakhina for invaluable advice and feedback on applying PCA to traffic anomaly detection.  ... 
doi:10.1145/1254882.1254895 dblp:conf/sigmetrics/RingbergSRD07 fatcat:kwdtcege3bew5fpzr7q4vqo2aq

Sensitivity of PCA for traffic anomaly detection

Haakon Ringberg, Augustin Soule, Jennifer Rexford, Christophe Diot
2007 Performance Evaluation Review  
In recent years, network-wide anomaly detection based on Principal Component Analysis (PCA) has emerged as a powerful method for detecting a wide variety of anomalies.  ...  Our study identifies and evaluates four main challenges of using PCA to detect traffic anomalies: (i) the false positive rate is very sensitive to small differences in the number of principal components  ...  ACKNOWLEDGMENTS The authors would like to thank Mark Crovella and Anukool Lakhina for invaluable advice and feedback on applying PCA to traffic anomaly detection.  ... 
doi:10.1145/1269899.1254895 fatcat:fw5owcue7zflfn5aqxxtpmu4xa

Sketch-based change detection

Balachander Krishnamurthy, Subhabrata Sen, Yin Zhang, Yan Chen
2003 Proceedings of the conference on Internet measurement conference - IMC '03  
We then implement a variety of time series forecast models (ARIMA, Holt-Winters, etc.) on top of such summaries and detect significant changes by looking for flows with large forecast errors.  ...  Directly applying existing techniques on a per-flow basis cannot scale up to the needs of such massive data streams.  ...  Top-N sketch vs. per-flow evaluation Here we are interested in exploring, for a given N, how many of the top-N flows (ranked in order of decreasing magnitude of forecasting errors) detected by the per-flow  ... 
doi:10.1145/948234.948236 fatcat:zex64mu4cjhi7ccnumgu7sz4yy

Detecting Invalid Associations between Fare Machines and Metro Stations Using Smart Card Data

Pengfei Zhang, Zhenliang Ma, Xiaoxiong Weng, Inhi Kim
2021 Journal of Advanced Transportation  
The tensor decomposition extracts features of passenger flows and travel times passing through fare machines.  ...  The proposed data-driven invalid data detection method is useful for large-scale data management in terms of data quality check and fix.  ...  We use the top-k accuracy measure.  ... 
doi:10.1155/2021/5283283 fatcat:pbobqnb6grartltlupl32ladve

Sketch-based change detection

Balachander Krishnamurthy, Subhabrata Sen, Yin Zhang, Yan Chen
2003 Proceedings of the 2003 ACM SIGCOMM conference on Internet measurement - IMC '03  
We then implement a variety of time series forecast models (ARIMA, Holt-Winters, etc.) on top of such summaries and detect significant changes by looking for flows with large forecast errors.  ...  Directly applying existing techniques on a per-flow basis cannot scale up to the needs of such massive data streams.  ...  Top-N sketch vs. per-flow evaluation Here we are interested in exploring, for a given N, how many of the top-N flows (ranked in order of decreasing magnitude of forecasting errors) detected by the per-flow  ... 
doi:10.1145/948205.948236 dblp:conf/imc/KrishnamurthySZC03 fatcat:xoooen75xvcs7iabuzt7pokyoy

Deep Learning and Traffic Classification: Lessons learned from a commercial-grade dataset with hundreds of encrypted and zero-day applications [article]

Lixuan Yang, Alessandro Finamore, Feng Jun, Dario Rossi
2021 arXiv   pre-print
extraction process of the DL backbone provides sizeable advantages for the detection of unknown classes.  ...  Additionally, we contribute to the problem of (ii) detection of zero-day applications by proposing a novel technique, tailored for DL models, that is significantly more accurate and light-weight than the  ...  ACKNOWLEDGEMENT We wish to thank the Editor and the anonymous Reviewers, whose feedback improved the quality of this paper.  ... 
arXiv:2104.03182v2 fatcat:pf7ict625vc53kqydgp2tz2eve

Exploiting Semantic Information and Deep Matching for Optical Flow [chapter]

Min Bai, Wenjie Luo, Kaustav Kundu, Raquel Urtasun
2016 Lecture Notes in Computer Science  
We tackle the problem of estimating optical flow from a monocular camera in the context of autonomous driving.  ...  We build on the observation that the scene is typically composed of a static background, as well as a relatively small number of traffic participants which move rigidly in 3D.  ...  Thus we perform cost aggregation on the union of label sets, and store only the top-K results after aggregation as final results c T i (s i ).  ... 
doi:10.1007/978-3-319-46466-4_10 fatcat:zmpui24d3bbv7n7pvdnowjj4aq

Exploiting Semantic Information and Deep Matching for Optical Flow [article]

Min Bai, Wenjie Luo, Kaustav Kundu, Raquel Urtasun
2016 arXiv   pre-print
We tackle the problem of estimating optical flow from a monocular camera in the context of autonomous driving.  ...  We build on the observation that the scene is typically composed of a static background, as well as a relatively small number of traffic participants which move rigidly in 3D.  ...  Thus we perform cost aggregation on the union of label sets, and store only the top-K results after aggregation as final results c T i (s i ).  ... 
arXiv:1604.01827v2 fatcat:l6ikg4y2gncchpjyl5zlz4ma6u

High Speed Elephant Flow Detection Under Partial Information [article]

Jordi Ros-Giralt, Alan Commike, Sourav Maji, Malathi Veeraraghavan
2018 arXiv   pre-print
top flows on the network with very high probability.  ...  We demonstrate on a real world 100 Gbps network that the BubbleCache algorithm helps reduce the computational cost by a factor of 1000 and the memory requirements by a factor of 100 while detecting the  ...  We can now formally introduce the concept of detection likelihood: Definition 2. Top flow detection likelihood.  ... 
arXiv:1701.01683v3 fatcat:y36z3qnzd5ghxa3ajbcw2lgq74

Motion fields to predict play evolution in dynamic sport scenes

Kihwan Kim, Matthias Grundmann, Ariel Shamir, Iain Matthews, Jessica Hodgins, Irfan Essa
2010 2010 IEEE Computer Society Conference on Computer Vision and Pattern Recognition  
Such analysis requires estimating the global movements of all players in the scene at any time, and is needed for modeling and predicting how the multi-agent play evolves over time on the field.  ...  To this end, we propose a novel approach to detect the locations of where the play evolution will proceed, e.g. where interesting events will occur, by tracking player positions and movements over time  ...  Acknowledgements: Thanks to Pixar Animation Studios, and specifically Jay Weiland, for coordinating the data capture session of a soccer games.  ... 
doi:10.1109/cvpr.2010.5540128 dblp:conf/cvpr/KimGSMHE10 fatcat:vws6e6vofngcfp25r257as7g5i

Detrimental effects of natural vertical head gradients on chemical and water level measurements in observation wells: identification and control

Alper Elçi, Gregory P. Flach, Fred J. Molz
2003 Journal of Hydrology  
submerged below the water table, and yet have an internal water level below the top of the screen.  ...  On a first order basis, the results for homogeneous aquifers may be used to estimate the behavior of a heterogeneous aquifer by computing a power-law average of the heterogeneous K h (z).  ...  This figure leaves little doubt concerning the potential importance of detecting and considering the effects of such flows on chemical concentration measurements.  ... 
doi:10.1016/s0022-1694(03)00201-4 fatcat:swddc4kvpfacrftctpyy2fgajy
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