Evaluation of Crowd Motion Direction Based on Wavelet Transform

2013 ◽  
Vol 846-847 ◽  
pp. 1106-1110
Author(s):  
Guo Qing Yang ◽  
Rong Yi Cui
Keyword(s):  
Wavelet Decomposition ◽  
Estimation Method ◽  
Motion Vectors ◽  
Motion Direction ◽  
Main Research ◽  
Object A ◽  
Coordinate Form ◽  
Direction Estimation ◽  
Polar Coordinate ◽  
Crowd Motion

Taking the wavelet decomposed approximate image as the main research object, a direction estimation method for moving object was proposed in this paper. Firstly, the approximate image for the frame of the video was obtained via wavelet decomposition; and furthermore, the motion estimation on the approximate image was achieved to obtain the motion vectors. Finally, the motion vectors were described as polar coordinate form to compute the number of motion vectors in specified angles and the information entropy of the motion directions. The experiment results show that the proposed method can remove the effect of noise and the results of direction estimation are consistent with the actual motion directions.

scholarly journals Faster processing of moving compared to flashed bars in awake macaque V1 provides a neural correlate of the flash lag illusion

2015 ◽  
Author(s):  
Manivannan Subramaniyan ◽  
Alexander S. Ecker ◽  
Saumil S. Patel ◽  
R. James Cotton ◽  
Matthias Bethge ◽  
...  
Keyword(s):  
Moving Object ◽  
Motion Processing ◽  
Neural Correlate ◽  
Compensatory Mechanisms ◽  
Motion Direction ◽  
Object A ◽  
Moving Stimuli ◽  
Natural Motion ◽  
Statistical Regularities ◽  
The Brain

AbstractWhen the brain has determined the position of a moving object, due to anatomical and processing delays, the object will have already moved to a new location. Given the statistical regularities present in natural motion, the brain may have acquired compensatory mechanisms to minimize the mismatch between the perceived and the real position of a moving object. A well-known visual illusion — the flash lag effect — points towards such a possibility. Although many psychophysical models have been suggested to explain this illusion, their predictions have not been tested at the neural level, particularly in a species of animal known to perceive the illusion. Towards this, we recorded neural responses to flashed and moving bars from primary visual cortex (V1) of awake, fixating macaque monkeys. We found that the response latency to moving bars of varying speed, motion direction and luminance was shorter than that to flashes, in a manner that is consistent with psychophysical results. At the level of V1, our results support the differential latency model positing that flashed and moving bars have different latencies. As we found a neural correlate of the illusion in passively fixating monkeys, our results also suggest that judging the instantaneous position of the moving bar at the time of flash — as required by the postdiction/motion-biasing model — may not be necessary for observing a neural correlate of the illusion. Our results also suggest that the brain may have evolved mechanisms to process moving stimuli faster and closer to real time compared with briefly appearing stationary stimuli.New and NoteworthyWe report several observations in awake macaque V1 that provide support for the differential latency model of the flash lag illusion. We find that the equal latency of flash and moving stimuli as assumed by motion integration/postdiction models does not hold in V1. We show that in macaque V1, motion processing latency depends on stimulus luminance, speed and motion direction in a manner consistent with several psychophysical properties of the flash lag illusion.

The muscle fiber direction estimation method by the pseudo-unipolar record

2011 ◽  
Author(s):  
Masaki Yoshida ◽  
Yuto Konishi ◽  
Hideo Nakamura ◽  
Takumu Hattori ◽  
Hisao Oka ◽  
...  
Keyword(s):  
Muscle Fiber ◽  
Estimation Method ◽  
Fiber Direction ◽  
Direction Estimation

scholarly journals Research on Detection and Location of Fluid-Filled Pipeline Leakage Based on Acoustic Emission Technology

Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 3628 ◽  
Author(s):  
Shengshan Pan ◽  
Zhengdan Xu ◽  
Dongsheng Li ◽  
Dang Lu
Keyword(s):  
Acoustic Emission ◽  
Wavelet Decomposition ◽  
Estimation Method ◽  
Reference Value ◽  
Time Delay Estimation ◽  
Operating Conditions ◽  
Support Vector ◽  
Acoustic Emission Sensor ◽  
Mode Decomposition ◽  
Acoustic Emission Sensors

Because of the inconvenience of installing sensors in a buried pipeline, an acoustic emission sensor is initially proposed for collecting and analyzing leakage signals inside the pipeline. Four operating conditions of a fluid-filled pipeline are established and a support vector machine (SVM) method is used to accurately classify the leakage condition of the pipeline. Wavelet decomposition and empirical mode decomposition (EMD) methods are initially used in denoising these signals to address the problem in which original leakage acoustic emission signals contain too much noise. Signals with more information and energy are then reconstructed. The time-delay estimation method is finally used to accurately locate the leakage source in the pipeline. The results show that by using SVM, wavelet decomposition and EMD methods, leakage detection in a liquid-filled pipe with built-in acoustic emission sensors is effective and accurate and provides a reference value for real-time online monitoring of pipeline operational status with broad application prospects.

scholarly journals A Specific Algorithm Based on Motion Direction Prediction

Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Zhesen Chu ◽  
Min Li
Keyword(s):  
Human Body ◽  
Body Position ◽  
Motion Vector ◽  
Human Motion ◽  
Generative Model ◽  
Experimental Results ◽  
Body Motion ◽  
Motion Vectors ◽  
Motion Direction ◽  
Current Frame

In this paper, we study the estimation of motion direction prediction for fast motion and propose a threshold-based human target detection algorithm using motion vectors and other data as human target feature information. The motion vectors are partitioned into regions by normalization to form a motion vector field, which is then preprocessed, and then the human body target is detected through its motion vector region block-temporal correlation to detect the human body motion target. The experimental results show that the algorithm is effective in detecting human motion targets in videos with the camera relatively stationary. The algorithm predicts the human body position in the reference frame of the current frame in the video by forward mapping the motion vector of the current frame, then uses the motion vector direction angle histogram as a matching feature, and combines it with a region matching strategy to track the human body target in the predicted region, thus realizing the human body target tracking effect. The algorithm is experimentally proven to effectively track human motion targets in videos with relatively static backgrounds. To address the problem of sample diversity and lack of quantity in a multitarget tracking environment, a generative model based on the conditional variational self-encoder conditional generation of adversarial networks is proposed, and the performance of the generative model is verified using pedestrian reidentification and other datasets, and the experimental results show that the method can take advantage of the advantages of both models to improve the quality of the generated results.

scholarly journals Geohazards Affecting Cultural Heritage Monuments. A Complex Case Study From Romania

2020 ◽  
Author(s):  
Dorina Camelia Ilies ◽  
Tudor Caciora ◽  
Grigore Vasile Herman ◽  
Alexandru Ilies ◽  
Madalina Ropa ◽  
...  
Keyword(s):  
Cultural Heritage ◽  
Low Cost ◽  
Three Dimensional ◽  
Field Research ◽  
Complex Case ◽  
Three Dimensional Model ◽  
Main Research ◽  
Object A ◽  
Extensive Field ◽  
The Impact

Abstract The impact that geohazards have on cultural heritage requires continuous research in order to assess risks, prevention and conservation. This study has as the main research object, a uniquen monument in terms of its connection with the risk phenomena. It is about a wooden church historical monument from the village of Corbești, Romania, which was destroyed at the beginning of the tenth decade of the last century by a meteorological hazard, later reconstructed on a new site (in Oradea Municipality), and currently there is a risk of being affected by a geological hazard. The study focused on three main directions of research, namely: reconstructing the film of events, analyzing current risks and finding viable methods for future conservation and promotion. The methodology is based on extensive field research and the use of digital technologies. The results obtained confirmed the church's tendency to be affected by the emergence of a new risk phenomenon - landslides. In order to conserve and rebuild in case of need, the monument was digitized and a three-dimensional model of high accuracy was developed. This approach has the advantage of being low-cost, fast, non-invasive and providing large volumes of valuable information in the process of cultural heritage conservation.

Fully Nonparametric Regression Estimation Based on Empirical Mode Decomposition

2012 ◽  
Vol 271-272 ◽  
pp. 932-935
Author(s):  
Hong Ying Hu ◽  
Wen Long Li ◽  
Feng Qiang Zhao
Keyword(s):  
Empirical Mode Decomposition ◽  
Wavelet Decomposition ◽  
Estimation Method ◽  
Regression Function ◽  
Regression Estimation ◽  
Function Estimation ◽  
Wavelet Regression ◽  
Nonparametric Regression Estimation ◽  
Mode Decomposition ◽  
Non Stationary Signal

Empirical Mode Decomposition (EMD) is a non-stationary signal processing method developed recently. It has been applied in many engineering fields. EMD has many similarities with wavelet decomposition. But EMD Decomposition has its own characteristics, especially in accurate trend extracting. Therefore the paper firstly proposes an algorithm of extracting slow-varying trend based on EMD. Then, according to wavelet regression estimation method, a new regression function estimation method based on EMD is presented. The simulation proves the advantages of the approach with easy computation and more accurate result.

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