Vibration Measurement with Video Processing based on Alternating Optimization of Frequency and Phase Shifts

This paper presents a practical framework and its applications of motion tracking algorithms applied to structural dynamics. Tracking points (“features”) across multiple images are a fundamental operation in many computer vision applications. The aim of this work is to show the capability of computer vision (CV) for estimating the dynamic characteristics of two mechanical systems using a noncontact, markerless, and simultaneous single input multiple output analysis. Kanade–Lucas–Tomasi trackers are used as virtual sensors on mechanical systems’ video from a high speed camera. First we introduce the paradigm of virtual sensors in the field of modal analysis using video processing. To validate our method, a simple experiment is proposed: an Oberst beam test with harmonic excitation (mode 1). Then with the example of a helicopter blade, frequency response functions’ (FRFs) reconstruction is carried out by introducing several signal processing enhancements (filtering and smoothing). The CV experimental results (frequencies and mode shapes) are compared with the classical modal approach and the finite element model (FEM) showing high correlation. The main interest of this method is that displacements are simply measured using only video at fps respecting the Nyquist frequency.

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Allelopathy in the tropical alga Lobophora variegata: An indirect cause of phase shifts on mesophotic coral reefs?

Planta Medica ◽

10.1055/s-0034-1382748 ◽

2014 ◽

Vol 80 (10) ◽

Author(s):

M Slattery ◽

MP Lesser

Keyword(s):

Coral Reefs ◽

Phase Shifts ◽

Lobophora Variegata

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Modern Technology for Image processing and Computer vision -A Review

Journal of Advanced Sciences and Engineering Technologies ◽

10.32441/jaset.v1i2.178 ◽

2018 ◽

Vol 1 (2) ◽

pp. 17-23

Author(s):

Takialddin Al Smadi

Keyword(s):

Image Processing ◽

Computer Vision ◽

Augmented Reality ◽

Video Compression ◽

Video Processing ◽

Vision System ◽

Citrus Fruit ◽

Modern Technology ◽

Image And Video Processing ◽

Depth Video

This survey outlines the use of computer vision in Image and video processing in multidisciplinary applications; either in academia or industry, which are active in this field.The scope of this paper covers the theoretical and practical aspects in image and video processing in addition of computer vision, from essential research to evolution of application.In this paper a various subjects of image processing and computer vision will be demonstrated ,these subjects are spanned from the evolution of mobile augmented reality (MAR) applications, to augmented reality under 3D modeling and real time depth imaging, video processing algorithms will be discussed to get higher depth video compression, beside that in the field of mobile platform an automatic computer vision system for citrus fruit has been implemented ,where the Bayesian classification with Boundary Growing to detect the text in the video scene. Also the paper illustrates the usability of the handed interactive method to the portable projector based on augmented reality. © 2018 JASET, International Scholars and Researchers Association

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