109 research outputs found

    A fast and robust hand-driven 3D mouse

    Get PDF
    The development of new interaction paradigms requires a natural interaction. This means that people should be able to interact with technology with the same models used to interact with everyday real life, that is through gestures, expressions, voice. Following this idea, in this paper we propose a non intrusive vision based tracking system able to capture hand motion and simple hand gestures. The proposed device allows to use the hand as a "natural" 3D mouse, where the forefinger tip or the palm centre are used to identify a 3D marker and the hand gesture can be used to simulate the mouse buttons. The approach is based on a monoscopic tracking algorithm which is computationally fast and robust against noise and cluttered backgrounds. Two image streams are processed in parallel exploiting multi-core architectures, and their results are combined to obtain a constrained stereoscopic problem. The system has been implemented and thoroughly tested in an experimental environment where the 3D hand mouse has been used to interact with objects in a virtual reality application. We also provide results about the performances of the tracker, which demonstrate precision and robustness of the proposed syste

    Dynamically parallel CAMSHIFT: GPU accelerated object tracking in digital video

    Get PDF
    The CAMSHIFT algorithm is widely used for tracking dynamically sized and positioned objects in real-time applications. In spite of its extensive study on the platform of sequential CPU, its research on massively parallel Graphical Processing Unit (GPU) platform is quite limited. In this work, we designed and implemented two different parallel algorithms for CAMSHIFT using CUDA. The first design performs calculations on the GPU, but requires iterative data transfers back to the host CPU for condition checking, which bottlenecks the entire program. In the second design, we propose an enhanced parallel reduction-based CAMSHIFT using dynamic parallelism to reduce overhead of data transfers between the CPU and GPU. Test results for a 400 by 400 search window show that the second design is up to five times faster than the first design and nine times faster than a pure CPU implementation. We also investigate the deployment of dynamic parallelism for multiple object tracking using CAMSHIFT --Leaf iv

    An Improved CAMSHIFT Tracking Algorithm Applying on Surveillance Videos

    Get PDF
    [[abstract]]In this paper, we present an improved version of CAMSHIFT algorithm applying on surveillance videos. A 2D, hue and brightness, histogram is used to describe the color feature of the target. In this way, videos with poor quality or achromatic points can be characterized better. The flooding process and contribution evaluation are executed to obtain a precise target histogram which reflects true color information and enhances discrimination ability. The proposed method is compared with existing methods and shows steady and satisfactory results.[[sponsorship]]Information Engineering Research Institute[[conferencedate]]20130303~20130304[[iscallforpapers]]Y[[conferencelocation]]Phuket, Thailan

    Real Time Object Detection & Tracking System (locally and remotely) with Rotating Camera

    Get PDF
    The task of real time detection and tracking of a moving object in a video stream is quite challenging if camera itself is moving. This paper presents an implementation of real time detection and tracking of an unknown object in video stream with 360° (azimuth) rotating camera. It also presents adaption of different object tracking algorithms and their effect on implementation. The system described in this paper contains a camera that is connected to an embedded system (standalone board) or PC/laptop. They (board/PC) are having an image processing algorithm which detects an object first and then tracks it as long as it is in the line of sight of the camera. As the object moves, the PC/laptop/embedded Board gives signal to motor to rotate the camera which is mounted on a stepper motor. To monitor Object in video user can have multiple options. If user is using laptop/PC to track object it is very simple for him because he already has a screen but in case of embedded board user can monitor the activity of the object of interest using HDMI output or streaming video on WEB server. The object can be defined directly by the end user by selecting a portion of the frame in video stream. The embedded board/PC also saves the video stream in a storage device for playback purpose. DOI: 10.17762/ijritcc2321-8169.150512

    Gravity optimised particle filter for hand tracking

    Get PDF
    This paper presents a gravity optimised particle filter (GOPF) where the magnitude of the gravitational force for every particle is proportional to its weight. GOPF attracts nearby particles and replicates new particles as if moving the particles towards the peak of the likelihood distribution, improving the sampling efficiency. GOPF is incorporated into a technique for hand features tracking. A fast approach to hand features detection and labelling using convexity defects is also presented. Experimental results show that GOPF outperforms the standard particle filter and its variants, as well as state-of-the-art CamShift guided particle filter using a significantly reduced number of particles

    Comparison between gaze and moving objects in videos for smooth pursuit eye movement evaluation

    Get PDF
    When viewing moving objects in videos the movement of the eyes is called smooth pursuit. For evaluating the relationship of eye tracking data to the moving objects, the objects in the videos need to be detected and tracked. In the first part of this thesis, a method for detecting and tracking of moving objects in videos is developed. The method mainly consists of a modified version of the Gaussian mixture model, The Tracking feature point method, a modified version of the Mean shift algorithm, Matlabs function bwlabel and a set of new developed methods. The performance of the method is highest when the background is static and the objects differ in colour from the background. The false detection rate increases, when the video environment becomes more dynamic and complex. In the second part of this thesis the distance between the point of gaze and the moving objects centre point is calculated. The eyes may not always follow the centre position of an object, but rather some other part of the object. Therefore, the method gives more satisfactory result when the objects are small.UtvĂ€rdering av smooth pursuit-rörelser. En jĂ€mförelse mellan ögonrörelser och rörliga objekt i videosekvenser PopulĂ€rvetenskaplig sammanfattning av examensarbetet: Andrea Åkerström Ett forskningsomrĂ„de som har vuxit mycket de senaste Ă„ren Ă€r ”eye tracking”: en teknik för att undersöka ögonrörelser. Tekniken har visat sig intressant för studier inom exempelvis visuella system, i psykologi och i interaktioner mellan datorer och mĂ€nniskor. Ett eye tracking system mĂ€ter ögonens rörelser sĂ„ att de punkterna ögat tittar pĂ„ kan bli estimerade. Tidigare har de flesta studier inom eye tracking baserats pĂ„ bilder, men pĂ„ senare tid har Ă€ven intresset för att studera filmsekvenser vuxit. Den typ av rörelse som ögat utför nĂ€r det följer ett rörligt objekt kallas för smooth pursuitrörelse. En av svĂ„righeterna med att utvĂ€rdera relationen mellan eye tracking-data och rörliga objekten i filmer Ă€r att objekten, antingen manuellt mĂ€ts ut eller att ett intelligent system utvecklas för en automatisk utvĂ€rdering. Det som gör processen att detektera och följa rörliga objekt i filmer komplex Ă€r att olika videosekvenser kan ha mĂ„nga olika typer av svĂ„ra videoscenarion som metoden mĂ„ste klara av. Till exempel kan bakgrunden i en video vara dynamisk, det kan finnas störningar som regn eller snö, eller kan problemet vara att kameran skakar eller rör sig. Syftet med detta arbete bestĂ„r av tvĂ„ delar. Den först delen, som ocksĂ„ har varit den största, har varit att utveckla en metod som kan detektera och följa rörliga objekt i olika typer av videosekvenser, baserad pĂ„ metoder frĂ„n tidigare forskning. Den andra delen har varit att försöka utveckla en automatisk utvĂ€rdering av ögonrörelsen smooth persuit, genom att anvĂ€nda de detekterade och följda objekten i videosekvenserna tillsammans med redan existerande ögondata. För att utveckla den metod har olika metoder frĂ„n tidigare forskning kombinerat. Alla metoder som har utvecklas i detta omrĂ„de har olika för och nackdelar och fungerade bĂ€ttre eller sĂ€mre för olika typer av videoscenarion. MĂ„let för metoden i detta arbete har varit att hitta en kombination av olika metoder som, genom att kompensera varandras för- och nackdelar, kan ge en sĂ„ bra detektering som möjligt för olika typer av filmsekvenser. Min metod Ă€r till största del uppbyggd av tre metoder: En modifierad version av Guasssian Mixture Model, Tracking Feature Point och en modifierad version av Mean Shift Algorithmen. Guassian Mixture Model-metoden anvĂ€nds för att detekterar pixlar i filmen som tillhör objekt som Ă€r i rörelse. Metoden tar fram dynamiska modeller av bakgrunden i filmen och detekterar pixlar som skiljer sig frĂ„n backgrundsmodellerna. Detta Ă€r en vĂ€l anvĂ€nd metod som kan hantera komplexa bakgrunder med periodiskt brus, men den ger samtidigt ofta upphov till felaktiga detektioner och den kan inte hantera kamerarörelser. För att hantera kamerarörelser anvĂ€nds Tracking Feature Point-metoden och pĂ„ sĂ„ sĂ€tt kompenseras denna brist hos Guassian Mixture Modell-metoden. Tracking Feature Point tar fram ”feature points” ut videobilder och med hjĂ€lp av dem kan metoden estimera kameraförflyttningar. Denna metod rĂ€knar dock endast ut de förflyttningar som kameran gör, men den tar inte hĂ€nsyn till om kameran roterar. Mean Shift Algoritm Ă€r en metod som anvĂ€nds för att rĂ€kna ut det rörliga objektets nya position i en efterföljande bild. För mitt arbete har endast delar av denna metod anvĂ€nds till att bestĂ€mma vilka detektioner av objekt i de olika bilderna som representerar samma objekt. Genom att ta fram modeller för objekten i varje bild, vilka sedan jĂ€mförs, kan metoden bestĂ€mma vilka objekt som kan klassas som samma objekt. Den metod som har utvecklat i detta arbete gav bĂ€st resultat nĂ€r bakgrunden var statisk och objektets fĂ€rg skiljde sig frĂ„n bakgrunden. NĂ€r bakgrunden blir mer dynamisk och komplex ökade mĂ€ngden falska detektioner och för vissa videosekvenser misslyckas metoden att detektera hela objekten. Den andra delen av detta arbetes syfte var att anvĂ€nda resultatet frĂ„n metoden för att utvĂ€rdera eye tracking-data. Den automatiska utvĂ€rderingen av ögonrörelsen smooth pursuit ger ett mĂ„tt pĂ„ hur bra ögat kan följa objekt som rör sig. För att utföra detta mĂ€ts avstĂ„ndet mellan den punkt som ögat tittar pĂ„ och det detekterade objektets centrum. Den automatiskt utvĂ€rderingen av smooth pursuit-rörelsen gav bĂ€st resultat nĂ€r objekten var smĂ„. För större objekt följer ögat inte nödvĂ€ndigtvis objektets mittenpunkt utan istĂ€llet nĂ„gon annan del av objektet och metoden kan dĂ€rför i dessa fall ge ett missvisande resultat. Detta arbete har inte resulterat i en fĂ€rdig metod utan det finns mĂ„nga omrĂ„den för förbĂ€ttringar. Exempelvis skulle en estimering av kamerans rotationer förbĂ€ttra resultaten. UtvĂ€rderingen av hur vĂ€l ögat följer rörliga objekt kan Ă€ven utvecklas mer, genom att konturerna av objekten berĂ€knades. PĂ„ detta sĂ€tt skulle Ă€ven avstĂ„ndet mellan punkterna ögat tittar pĂ„ och objektets area kunnat bestĂ€mmas. BĂ„de eye tracking och att detektera och följa rörliga objekt i filmer Ă€r idag aktiva forskningsomrĂ„den och det finns alltsĂ„ fortfarande mycket att utveckla i dessa omrĂ„den. Syfte med detta arbete har varit att försöka utveckla en mer generell metod som kan fungera för olika typer av filmsekvenser

    MULTI-OBJECT TRACKING USING ST-MRF, GMM, MODIFIED RUNNING AVERAGE AND CAMSHIFT - A COMPARATIVE STUDY

    Get PDF
    Video-based object tracking in static or in dynamic scenes is one of the challenging problems with vast variety of applications, is currently one of the most active research topics in computer vision. This paper mainly focuses on performing survey on tracking moving objects in video scenes in both pixel-domain and compressed-domain with detailed descriptions of tracking strategies and examining their pros and cons. Survey of tracking methodologies in both pixel and compressed domain for object recognition and tracking includes modified running average, Gaussian Mixture Model, Spatial-temporal MRF and Camshift. Experimental result has been evaluated for different video sequences with different conditions such as noise; illumination changes, shadow, scale change in the objects etc. estimate the performance of these algorithms. Result obtained has better accuracy, good performances and with the consumption of less processing time according to the evaluation criteria
    • 

    corecore