• 제목/요약/키워드: Video Length

검색결과 308건 처리시간 0.027초

ATM 망에서 웨이브릿 변환을 이용한 계층부호화 영상 전송에 관한 연구 (A Study on transmission of layered images using Wavelet transform over ATM)

  • 이한영;송재연
    • 전자공학회논문지T
    • /
    • 제35T권2호
    • /
    • pp.35-38
    • /
    • 1998
  • ATM 기술과 패킷망의 발전에 따라 음성, 데이터, 영상 전송의 필요성이 증가되고 있다. ATM에서는 데이타 손실을 최소화하기 위하여 셀로 불리우는 일정길이의 데이타로 나누어 진다. ATM에서는 송신시 부호를 고정하지 않고 버리기 때문에 영상신호 전송에서는 계층부호화 방법을 사용한다. 따라서 본 논문에서는 계층부호화 방법인 웨이브릿 변환을 이용한 부호화를 시뮬레이션 하였다.

  • PDF

Digital Holographic Display System with Large Screen Based on Viewing Window Movement for 3D Video Service

  • Park, Minsik;Chae, Byung Gyu;Kim, Hyun-Eui;Hahn, Joonku;Kim, Hwi;Park, Cheong Hee;Moon, Kyungae;Kim, Jinwoong
    • ETRI Journal
    • /
    • 제36권2호
    • /
    • pp.232-241
    • /
    • 2014
  • A holographic display system with a 22-inch LCD panel is developed to provide a wide viewing angle and large holographic 3D image. It is realized by steering a narrow viewing window resulting from a very large pixel pitch compared to the wave length of the laser light. Point light sources and a lens array make it possible to arbitrarily control the position of the viewing window for a moving observer. The holographic display provides both eyes of the observer with a holographic 3D image using two vertically placed LCD panels and a beam splitter to support the holographic stereogram.

Development of an Algorithm to Measure the Road Traffic Data Using Video Camera

  • Kim, Hie-Sik;Kim, Jin-Man
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2002년도 ICCAS
    • /
    • pp.95.2-95
    • /
    • 2002
  • 1. Introduction of Camera Detection system Camera Detection system is an equipment that can detect realtime traffic information by image processing techniques. This information can be used to analyze and control road traffic flow. It is also used as a method to detect and control traffic flow for ITS(Intelligent Transportation System). Traffic information includes speed, head way, traffic flow, occupation time and length of queue. There are many detection systems for traffic data. But video detection system can detect multiple lanes with only one camera and collect various traffic information. So it is thought to be the most efficient method of all detection system. Though the...

  • PDF

철도역사 안전을 위한 비전기반 승강장 모니터링 시스템 (Vision based Monitoring System for Safety in Railway Station)

  • 오세찬;박성혁;이장무
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2007년도 춘계학술대회 논문집
    • /
    • pp.953-958
    • /
    • 2007
  • Passenger safety is a primary concern of railway system but, it has been urgent issue that dozens of people are killed every year when they are fallen from train platforms. In this paper, we propose a vision based monitoring system for railway station platform. The system immediately perceives dangerous factors of passengers on the platform by using image processing technology. To monitor almost entire length of the track line in the platform, we use several video cameras. Each camera conducts surveillance its own preset monitoring area whether human or dangerous object was fallen in the area. Moreover, to deal with the accident immediately, the system provides local station, central control room employees and train driver with the video information about the accident situation including alarm message. This paper introduces the system overview and detection process with experimental results. According to the results, we expect the proposed system will play a key role for establishing highly intelligent monitoring system in railway.

  • PDF

Discrete Cosine Transformer with Variable-Length Basis Vector for MPEG-4 Video Codec

  • Kuroda, Ryo;Fujita, Gen;Onoye, Takao;Shirakawa, Isao
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2000년도 ITC-CSCC -2
    • /
    • pp.811-814
    • /
    • 2000
  • It this paper a VLSI architecture of the Shape-Adaptive Discrete Cosine Transform (SA-DCT) is described, which can be employed dedicatedly for MPEG-4 video codec. Adopting a fast DCT algorithm, the number of multipliers can be reduced by half in comparison with a conventional algorithm. This SA-DCT core with a small additional amount of hardware can perform the SA-Inverse DCT (SA-IDCT) by sharing multipliers and a transportation memory. The proposed SA-DCT core is integrated with 40,000 gates by using 0.35$mu$m triple-metal CMOS technology, which operates at 20 Mhz, and hence enables the realtime codec of CIF ($352{\times}288$ pixels) pictures.

  • PDF

VISUAL MEASUREMENT METHOD USING A CIRCULAR GROOVE IMAGE FOR MEASURING INTERNAL DEFECTS OF PIPES IN NUCLEAR POWER PLANT

  • Choi, Young-Soo;Jeong, Kyung-Min;Lee, Sung-Uk;Jung, Seung-Ho
    • Nuclear Engineering and Technology
    • /
    • 제40권5호
    • /
    • pp.419-428
    • /
    • 2008
  • During the overhaul period of nuclear power plants in Korea, an ROV(Remotely Operated Vehicle) enters the cold-leg pipes connected with the reactor to examine the state of the thermal sleeves and their positions in the safety injection nozzles. To measure the positions of the thermal sleeves or scratches with video images recorded during the examination, time-varying camera parameters should be known, such as the focal length and principal points used for the capturing each video image. In this paper, we propose a camera calibration and measurement scheme by using a single image containing two circular grooves of a cylindrical nozzle whose radius and distance are known.

A Study on the Experiential Response of Short-Form Video Users

  • Lim, Dong Kyun
    • International journal of advanced smart convergence
    • /
    • 제10권4호
    • /
    • pp.273-277
    • /
    • 2021
  • As society gradually enters a virtual, non-face-to-face society, the use of online content is increasing as well. In particular, as smartphones are thoroughly established in our daily life, the platforms of webtoons, mobile broadcasting, and education are shifting from personal computers to smartphones. Recently, the development of the Over-The-Top media service (OTT service) enabled streaming services of various media contents through the internet and activation of IPTV. Therefore, the rapid increase of popularity of short-form content is a natural phenomenon with smartphone platforms with fast, improvised, and endless communication. Lately, TikTok became the favored platform with prosumers, defined as people who are both producers and consumers. In this study, I studied the experiential response of YouTube and TikTok users as representative examples of a short-form content platform developed after the 2000s, the flourishing years of digital content with a length of 30 seconds.

Elimination of Screen-Flickering Phenomenon in Multi-Function Display During Flight of Fixed-Wing Aircraft

  • Kwon, Jung-Hyuk;Kwon, Ik-Hyun;Beak, Jun-Ho;Jang, Geun-Hyung;Lee, Wang-Sang
    • 항공우주시스템공학회지
    • /
    • 제15권2호
    • /
    • pp.45-51
    • /
    • 2021
  • In this study, we aim to eliminate the flickering phenomenon in multi-function display (MFD) units during the flight of fixed-wing aircraft. To execute flight missions effectively, the video signals transmitted to MFDs must provide information accurately and seamlessly. Therefore, a method for addressing the flickering phenomenon-including cause analysis and failure diagnosis-is adopted; specifically, a wiring configuration with a direct connection between the video signal cables and with a short cable length is adopted. The proposed method is experimentally verified using a flight test.

Comparative Analysis of Gait Parameters and Symmetry between Preferred Walking Speed and Walking Speed by using the Froude Number

  • Yoo, Si-Hyun;Kim, Jong-Bin;Ryu, Ji-Seon;Yoon, Suk-Hoon;Park, Sang-Kyoon
    • 한국운동역학회지
    • /
    • 제26권2호
    • /
    • pp.221-228
    • /
    • 2016
  • Objective: The purpose of this study was to investigate differences in gait parameters and symmetry between walking speed by using the Froude number and preferred walking speed. Method: Fifty adults (age: $21.0{\pm}1.7years$, body weight: $71.0{\pm}9.2kg$, height: $1.75{\pm}0.07m$, leg length: $0.89{\pm}0.05m$) participated in this study. Leg length-applied walking speed was calculated by using the Froude number, defined as Fr = ${\upsilon}^2$/gL, where v is the velocity, g is the gravitational acceleration, and L is the leg length. Video data were collected by using eight infrared cameras (Oqus 300, Qualysis, Sweden) and the Qualisys Track Manager software (Qualisys, Sweden), with a 200-Hz sampling frequency during two-speed walking (preferred walking speed [PS] and leg length-applied walking speed [LS]) on a treadmill (Instrumented Treadmill, Bertec, USA). The step length, stride length, support percentage, cadence, lower joint angle, range of motion (ROM), and symmetry index were then calculated by using the Matlab R2009a software. Results: Step and stride lengths were greater in LS than in PS (p < 0.05). The right single-support percentage was greater in LS than in PS (p < 0.05). The hip joint angle at heel contact and toe-off were greater in LS than in PS (p < 0.05). The hip and knee joint ROM were greater in LS than in PS (p < 0.05). Conclusion: Based on our findings, we suggest that increased walking speed had a significant effect on step length, stride length, support percentage, and lower joint ROM.

보행속도에 따른 보폭변화가 하지관절 모멘트에 미치는 영향 (The Influence of Step Length at Different Walking Speed on the Moment of the Lower Limb Joint)

  • 김로빈;진영완;문곤성
    • 한국운동역학회지
    • /
    • 제15권2호
    • /
    • pp.93-102
    • /
    • 2005
  • The purpose of this study was to examine the effect of step length on the joint moment. The subjects were 4 undergraduate and graduate students in their 20s with normal legs. The subjects were individually tested by the running timer at the walking speed of 0.67m/s, 134m/s, and 2.46m/s. The step length was regulated to -10% of normal, normal and +10% of normal step length using foot print. The walking performances of each subjects were filmed using a high speed video camera. The raw data were analyzed by LabVIEW Graphical Program and these data were analyzed by ANOVAs and Scheffe. The results of this study were as follows: The maximum dorsiflexion moment of the ankle joint increased as the step length increased only at the fast walking speed. Although there wasn't significant difference shown in the plantar flexion moment, regular pattern in the plantar flexion moment which increased as the step length increased was found. The first maximum extension moment of the knee joint increased only at the normal walking speed, but there appeared no significant difference in the maximum flexion and second extension moment. The maximum extension moment of the hip joint increased at the normal and fast walking speed. Although there wasn't significant difference, regular pattern in flexion moment which increased as the step length increased was found.