• Title/Summary/Keyword: camera image

Search Result 4,922, Processing Time 0.036 seconds

Accuracy Comparison Between Image-based 3D Reconstruction Technique and Terrestrial LiDAR for As-built BIM of Outdoor Structures

  • Lee, Jisang;Hong, Seunghwan;Cho, Hanjin;Park, Ilsuk;Cho, Hyoungsig;Sohn, Hong-Gyoo
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.33 no.6
    • /
    • pp.557-567
    • /
    • 2015
  • With the increasing demands of 3D spatial information in urban environment, the importance of point clouds generation techniques have been increased. In particular, for as-built BIM, the point clouds with the high accuracy and density is required to describe the detail information of building components. Since the terrestrial LiDAR has high performance in terms of accuracy and point density, it has been widely used for as-built 3D modelling. However, the high cost of devices is obstacle for general uses, and the image-based 3D reconstruction technique is being a new attraction as an alternative solution. This paper compares the image-based 3D reconstruction technique and the terrestrial LiDAR in point of establishing the as-built BIM of outdoor structures. The point clouds generated from the image-based 3D reconstruction technique could roughly present the 3D shape of a building, but could not precisely express detail information, such as windows, doors and a roof of building. There were 13.2~28.9 cm of RMSE between the terrestrial LiDAR scanning data and the point clouds, which generated from smartphone and DSLR camera images. In conclusion, the results demonstrate that the image-based 3D reconstruction can be used in drawing building footprint and wireframe, and the terrestrial LiDAR is suitable for detail 3D outdoor modeling.

Methods of Subjective Image Quality Evaluation in Pictorial Images (사진의 주관적 화질 평가 방법; 요인 분석을 통한 평가 항목 선정을 중심으로)

  • Noh, Yeon-Sook;Har, Dong-Hwan
    • The Journal of the Korea Contents Association
    • /
    • v.10 no.8
    • /
    • pp.186-197
    • /
    • 2010
  • Recent changes show that the goals of reproduction devices have changed from accurately reproducing scenes to improving user preference. It implies that the directions in developing cameras, the most common reproduction devices, are moving from performance-centered to quality-centered, from developers to users. Accepting such changes demand new standards in evaluating reproduction devices. This paper suggests a new method to evaluate the quality of images, based on cognitive properties of users. The quality of an image is a result oriented from the interaction of various attributes, therefore some functional tests are not enough to evaluate total quality of an image. In this respect, an evaluation model which integrates various physical attributes of an image is needed, that enables a third observer to subjectively evaluate the total quality of an image. In this paper, the experiment was carried out to 127 subjects, with the 84 test stimuli and 11 evaluation factors, followed by an factor analysis. The evaluation factors to assess the quality of images in this paper includes the results by cognitions of users and the properties of reproduction, the factors not only evaluate the quality but suggest how to improve them.

The software configuration management system for image processing algorithm development (영상처리 알고리즘 개발을 위한 소프트웨어형상관리시스템)

  • Lee Jeong-Heon;Chae Ok-Sam
    • The KIPS Transactions:PartB
    • /
    • v.12B no.1 s.97
    • /
    • pp.1-8
    • /
    • 2005
  • The importance of software is getting high in development of the digital device (digital camcoder, digital camera, mp3 player, ....). And because the sire of software becomes larger and complicated, the necessity of software configuration management (to solves a software crisis) is increased. The general software configuration management system shows lack of the property and features of software development environment for image processing algorithm due to its wide range to be covered. Image processing algorithm development environment has properties like repetitive analysis and simulation using visual programming environment where, beside support of elementary development functions. component(or library) can be combined and tested interactively. Moreover, the method to look fast and effectively for component having similar function is required. In this paper, we present the system which supports the software configuration management method for a simulation tool and the property in the visual programming environment. And we relate our system to real simulation tool so as to check its ability as the software configuration management system for image processing algorithm development environment.

Improvement of Frame Rate of Electro-Optical Sensor using Temporal Super Resolution based on Color Channel Extrapolation (채널별 색상정보 외삽법 기반 시간적 초해상도 기법을 활용한 전자광학 센서의 프레임률 향상 연구)

  • Noh, SangWoo
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.18 no.5
    • /
    • pp.120-124
    • /
    • 2017
  • The temporal super resolution is a method for increasing the frame rate. Electro-optical sensors are used in various surveillance and reconnaissance weapons systems, and the spatial resolution and temporal resolution of the required electro-optical sensors vary according to the performance requirement of each weapon system. Because most image sensors capture images at 30~60 frames/second, it is necessary to increase the frame rate when the target moves and changes rapidly. This paper proposes a method to increase the frame rate using color channel extrapolation. Using a DMD, one frame of a general camera was adjusted to have different consecutive exposure times for each channel, and the captured image was converted to a single channel image with an increased frame rate. Using the optical flow method, a virtual channel image was generated for each channel, and a single channel image with an increased frame rate was converted to a color channel image. The performance of the proposed temporal super resolution method was confirmed by the simulation.

ACCURACY ASSESSMENT BY REFINING THE RATIONAL POLYNOMIALS COEFFICIENTS(RPCs) OF IKONOS IMAGERY

  • LEE SEUNG-CHAN;JUNG HYUNG-SUP;WON JOONG-SUN
    • Proceedings of the KSRS Conference
    • /
    • 2004.10a
    • /
    • pp.344-346
    • /
    • 2004
  • IKONOS 1m satellite imagery is particularly well suited for 3-D feature extraction and 1 :5,000 scale topographic mapping. Because the image line and sample calculated by given RPCs have the error of more than 11m, in order to be able to perform feature extraction and topographic mapping, rational polynomial coefficients(RPCs) camera model that are derived from the very complex IKONOS sensor model to describe the object-image geometry must be refined by several Ground Control Points(GCPs). This paper presents a quantitative evaluation of the geometric accuracy that can be achieved with IKONOS imagery by refining the offset and scaling factors of RPCs using several GCPs. If only two GCPs are available, the offsets and scale factors of image line and sample are updated. If we have more than three GCPs, four parameters of the offsets and scale factors of image line and sample are refined first, and then six parameters of the offsets and scale factors of latitude, longitude and height are updated. The stereo images acquired by IKONOS satellite are tested using six ground points. First, the RPCs model was refined using 2 GCPs and 4 check points acquired by GPS. The results from IKONOS stereo images are reported and these show that the RMSE of check point acquired from left images and right are 1.021m and 1.447m. And then we update the RPCs model using 4 GCPs and 2 check points. The RMSE of geometric accuracy is 0.621 m in left image and 0.816m in right image.

  • PDF

An efficient Color Edge Fuzzy Interpolation Method for improving a Chromatic Aberration (색수차 개선을 위한 효율적인 컬러 에지 퍼지 보간 방법)

  • Byun, Oh-Sung
    • Journal of the Korea Society of Computer and Information
    • /
    • v.15 no.10
    • /
    • pp.59-70
    • /
    • 2010
  • Each pixels become got pixel value for color of only one from among colors because of bayer pattern that light receiving device of image sensor which is used in HHP and digital camera writes only one color. Information of the missing pixels could infer perfect color image from using information of neighbor pixels by using CFA(Color Filter Array). In this paper, we derive relation between the average of the data from the light receiving device of image sensor and each color channel data. And by using this relation, a new efficient edge color fuzzy method for color interpolation is proposed. Also, missing luminance signal channel interpolation was fuzzy interpolation along any edges direction for reducing color noise and interpolating efficiently it. And in this paper, the proposed method has been proved improving average 2.4dB than the conventional method by using PSNR. Also, resolution of the image of the proposed method was similar to the original image by visual images, we has been verified to be decreased a chromatic aberration than image of conventional algorithms with simulation result.

The Robust Augmented Reality System in The Rapid change of Brightness Using The Histogram Specification and Kalman Filter (히스토그램 명세화와 칼만 필터를 이용한 급격한 밝기 변화에 강건한 증강현실 시스템)

  • Kim, Kee-Baek;Lee, Seok-Han;Choi, Jong-Soo
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.48 no.2
    • /
    • pp.1-10
    • /
    • 2011
  • In this paper, we propose the algorithm for the AR(Augmented Reality) system, which is robust to the brightness change of light. In the proposed method, the histogram specification is achieved using the sample histogram, obtained from the frames in which the target objects could be detected successful. And When the object key-points couldn't be detected by the displacement of camera positions, the positions of non-detected key-points ware estimated using the linear KF(Kalman Filter). When the proposed algorithm is applied in the AR systems, the object key-points can be detected three times as much as the existing others. In addition, to prove the more efficiency of the proposed algorithm, we implemented the AR game, and could know that the performance is the more advanced than the others. The proposed algorithm can be used for the AR environments, which high efficiency is required such as the AR game, or the implementation of AR systems which are robust to the change of lights, etc.

Indoor Location Positioning System for Image Recognition based LBS (영상인식 기반의 위치기반서비스를 위한 실내위치인식 시스템)

  • Kim, Jong-Bae
    • Journal of Korea Spatial Information System Society
    • /
    • v.10 no.2
    • /
    • pp.49-62
    • /
    • 2008
  • This paper proposes an indoor location positioning system for the image recognition based LBS. The proposed system is a vision-based location positioning system that is implemented the augmented reality by overlaying the location results with the view of the user. For implementing, the proposed system uses the pattern matching and location model to recognize user location from images taken by a wearable mobile PC with camera. In the proposed system, the system uses the pattern matching and location model for recognizing a personal location in image sequences. The system is estimated user location by the image sequence matching and marker detection methods, and is recognized user location by using the pre-defined location model. To detect marker in image sequences, the proposed system apply to the adaptive thresholding method, and by using the location model to recognize a location, the system can be obtained more accurate and efficient results. Experimental results show that the proposed system has both quality and performance to be used as an indoor location-based services(LBS) for visitors in various environments.

  • PDF

Multi-spectral Imaging-based Color Image Reconstruction Using the Conventional Bayer CFA (베이어 CFA 카메라를 사용한 다중 스펙트럼 기반 컬러영상 생성 기술)

  • Shin, Jeong-Ho
    • Journal of Broadcast Engineering
    • /
    • v.16 no.3
    • /
    • pp.561-565
    • /
    • 2011
  • This paper presents an imaging system for reconstruction of enhanced color images using the conventional Bayer CFA. By extracting various colors such as RGBCY from two sequential images which consist of a image by broadband G channel lens filter and the other image captured without one, the proposed color image reconstruction system can reduce the computational complexity for demosaicking and make high resolution color information without aliasing artifacts. Because the proposed system uses the common Bayer CFA image sensor, fabricating a new type of CFA is not necessary for obtaining a multi-spectral image, which can be easily extensible for applications of multi-spectral imaging. Finally, in order to verify the performance of the proposed system, experimental results are performed. By comparing with the existing demosaicking methods, the proposed camera system showed the significant improvements in the sense of color resolution.

Development of a Surface Roughness Measurement Method Using Reflected Laser Beam Image and Its Application (레이저광 반사 화상을 이용한 표면 거칠기 측정법의 개발과 적용)

  • Yun, Yun-Feng-Shen;Kim, haa-young;An, jung-hwan;Chi, ei-jon
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.18 no.11
    • /
    • pp.51-57
    • /
    • 2001
  • A light beam reflected from a machined surface generally containes information concerning about its surface roughness. This study examines and proposes a surface roughness measurement technique for on-machine measurement of machined surfaces. The technique is based on the measurement of a reflected laser beam pattern and the statistical analysis of its light intensity distribution. The surface roughness was found to be closely related to the standard deviation of the light intensity on the primary axis of the reflected pattern. An image acquisition device is made up of a laser diode, a half mirror, a screen, and a CCD camera. The exact image with the primary and secondary axes of a reflected laser beam pattern is calculated through such image processing algorithm as thresholding, edge detection, image rotation, segmentation, etc. A median filter and a surrounding light correction algorithm are improve the image quality and reduce the measuring error. Using the developed measuring device the effect of screen materials and workpiece and workpiece materials was investigated. Experimental results regarding to relatively high-quality surfaces machined by grinding, polishing, lapping processes have shown the measurement error is within 10% in the range of $0.1{mu}m~0.8{\mu}m R_q.$Therefore, the proposed method is thought to be effectively used when quick measurements is needed with workpieces fixed on the machine.

  • PDF