• Title/Summary/Keyword: 계산 사진학

Search Result 97, Processing Time 0.028 seconds

Paradigm Shift of Camera: Part I. Computational Photography (카메라의 패러다임 전환: Part I. 계산 사진학의 태동)

  • Jeong, Kyu-Man
    • Journal of the Korea Computer Graphics Society
    • /
    • v.15 no.4
    • /
    • pp.23-30
    • /
    • 2009
  • From the beginning of 21st century, digital cameras became popular. In computer graphics community, much re search has been done using photographs taken by digital cameras. This kind of research is categorized as computational photography. The purpose of this paper is to explain the appearance of computational photography in the history of photography. Moreover, the history of photography is explained as a series of paradigm shifts. Based on the analysis, future research directions of computational photography will be given.

  • PDF

Recalculation of Monthly Weather Table for Construction Standard Cost Estimating on Aerial Photogrammetry (항공사진측량 품셈 개정을 위한 월별천후표 재계산)

  • Song, DongSeob
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.37 no.6
    • /
    • pp.571-577
    • /
    • 2019
  • Since the introduction of digital cameras in an aerial-photogrammetry field on 2006, the technological paradigm related to the photogrammetry has been shifting from the analog types to digital types. However, current construction standard cost for the aerial-photogrammetry and the digital mapping are being mixed with analog-based concepts and digital-based methods. In the current standard cost, the monthly weather table is closely related to the calculation of the number of flying days in a taking of aerial photograph. The current monthly weather table uses the results calculated from the observation data of total cloud amount from 1999 to 2007. In this study, the monthly weather table was calculated using the total cloud data during ten years from 2009 to 2018. As a result, the newly calculated number of clear days for 29 stations was analyzed as 44 days decreased by 6 days. The maximum number of clear days decreased in Jinju as 23 days, and the highest decreased clearing days was February.

Application of Area Based Matching for the Automation of Interior Orientation (내부표정의 자동화를 위한 영역중심 영상정합기법 적용)

  • 유복모;염재홍;김원대
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.17 no.4
    • /
    • pp.321-330
    • /
    • 1999
  • Automation of observation and positioning of fiducial marks is made possible with the application of image matching technique, developed through the cooperative research effort of computer vision and digital photogrammetry. The major problem in such automation effort is to minimize the computing time and to increase the positional accuracy. Except for scanning and ground control surveying, the interior orientation process was automated in this study, through the development of an algorithm which applies the image matching and image processing techniques. The developed system was applied to close-range photogrammetry and the analysis of the results showed 54% improvement in processing time. For fiducial mark observation during interior orientation, the Laplacian of Gaussian transformation and the Hough transformation were applied to determine the accurate position of the center point, and the correlation matching and the least squares matching method were then applied to improve the accuracy of automated observation of fiducial marks. Image pyramid concept was applied to reduce the computing time of automated positioning of fiducial mark.

  • PDF

Platform Calibration of an Aerial Multi-View Camera System (항공용 다각사진 카메라 시스템의 플랫폼 캘리브레이션)

  • Lee, Chang-No;Kim, Chang-Jae;Seo, Sang-Il
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.28 no.3
    • /
    • pp.369-375
    • /
    • 2010
  • Since multi-view images can be utilized for 3D visualization and surveying as well, a system calibration is an essential procedure. The cameras in the system are mounted to the holder and their locations and attitudes are relatively fixed. Therefore, the locations and the attitudes of the perspective centers of the four oblique looking cameras can be calculated using the location and attitude of the nadir looking camera and the boresight values between the cameras. In this regard, this research is focusing on the analysis of the relative location and attitude between the nadir and oblique looking cameras based on the results of the exterior orientation parameters after the aerial triangulation of the real multiview images. We acquired high standard deviations of the relative locations between the nadir and oblique cameras. Standard deviations of the relative attitudes between the cameras were low when only the exterior orientations of the oblique looking cameras were allowed to be adjusted. Moreover, low standard deviations of the relative attitudes came when we considered not all the exterior orientations of the cameras but the attitudes of them only.

Experiment on Camera Platform Calibration of a Multi-Looking Camera System using single Non-Metric Camera (비측정용 카메라를 이용한 Multi-Looking 카메라의 플랫폼 캘리브레이션 실험 연구)

  • Lee, Chang-No;Lee, Byoung-Kil;Eo, Yang-Dam
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.26 no.4
    • /
    • pp.351-357
    • /
    • 2008
  • An aerial multi-looking camera system equips itself with five separate cameras which enables acquiring one vertical image and four oblique images at the same time. This provides diverse information about the site compared to aerial photographs vertically. The geometric relationship of oblique cameras and a vertical camera can be modelled by 6 exterior orientation parameters. Once the relationship between the vertical camera and each oblique camera is determined, the exterior orientation parameters of the oblique images can be calculated by the exterior orientation parameters of the vertical image. In order to examine the exterior orientation of both a vertical camera and each oblique cameras in the multi-looking camera relatively, calibration targets were installed in a lab and 14 images were taken from three image stations by tilting and rotating a non-metric digital camera. The interior orientation parameters of the camera and the exterior orientation parameters of the images were estimated. The exterior orientation parameters of the oblique image with respect to the vertical image were calculated relatively by the exterior orientation parameters of the images and error propagation of the orientation angles and the position of the projection center was examined.

A Case Study on Team Project in Calculus for Medicine - Numerical Methods of Integration - (의대생을 위한 미분적분학 팀프로젝트 사례 - 정적분의 수치채산법을 중심으로 -)

  • Min, Sook
    • Communications of Mathematical Education
    • /
    • v.26 no.2
    • /
    • pp.155-176
    • /
    • 2012
  • In this paper, we present a practical and essential method of using team projects for calculus. We, specifically, take into account the team project that calculate the volume of lung represented on CT scan images. We have demonstrated that the process of analyzing the images in a team project encourage studying numerical methods of integration for calculus. Also, we have used various technological programs(MATLAB, MATHEMATICA, MS Excel) to solve the team project.

History Management Technology of Building Construction and Maintenance Using Vector Photo Information and BIM (벡터사진 정보와 BIM을 활용한 건축물의 시공·유지관리 이력관리기술)

  • Kim, Kyoon-Tai;Lim, Myung-Gu;Kim, Gu-Taek
    • Journal of the Korea Institute of Building Construction
    • /
    • v.14 no.6
    • /
    • pp.605-613
    • /
    • 2014
  • Recently proposed intelligent images are generating, storing and managing along with existing image information and 5W1H information. Therefore, these vector images can be useful in searching and managing photos taking during building construction and maintenance processes. In addition, when the vector photos, a key to the intelligent image, is linked with BIM, it is possible to find BIM objects by utilizing information included in vector photos. And if the taken vector photo is saved as attributes of the extracted object, the vector photo can be managed as the historical data. Furthermore, this new technology will contribute to make the management of construction information more efficiently. This study is about the development of the technology of extracting BIM objects from vector photo information and managing the attributes of the extracted objects. Also the prototype modules was developed and tested to evaluate the processes of setting reference points, converting coordinate system, calculating positions, and so on. Through these processes, it was confirmed that the possibility of extracting BIM objects from vector photos and of managing attribute data of objects.

Three-dimensional CT image study on the correction of gonial angle width enlarged on frontal cephalogram (정모두부방사선사진에서 하악골 우각부 영상확대 및 이의 보정에 관한 3차원 CT영상 연구)

  • Hwang, Hyeon-Shik;Eun, Chun-Sun;Hwang, Chung Hyon;Lim, Hoi-Jeong
    • The korean journal of orthodontics
    • /
    • v.35 no.4 s.111
    • /
    • pp.251-261
    • /
    • 2005
  • Enlargement is an inherent property of X-rays which occurs when straight hues diverse from small a focal spot. The purpose of the present study was to evaluate the validity of the correction of gonial angle width enlarged on frontal cephalogram, using frontal and lateral cephalograms taken orthogonally from each other. In 40 adult individuals, frontal and lateral cephalograms were taken at a $90^{\circ}$ angle using the Head Posture Aligner. The angle width was measured on the frontal cephalogram and subsequently. the corrected angle width was calculated using the magnification rate of two cephalograms. Measured and corrected angle widths were compared with the measurement from the 3D CT image. The measurement or the frontal cephalogram showed a 9.10mm of enlargement on average ranging from 7.92 to 11.31mm. Corrected angle width measurement showed a 0.14mm difference with the 3D CT image measurement, which was not statistically significant. The results of the study indicate that actual au91e width can be approached through calculation using frontal and lateral cephalograms taken orthogonally with the help of the Head Posture Aligner The study also showed that the magnitude of correction error did not show a significant correlation with the amount of menton deviation, and it suggests that the present correction method is valid even in individuals with severe facial asymmetry.

Investigation of Shoreline Change by Photogrammetric Method (항공사진측량에 의한 해안선 변화 조사)

  • Lee, Chang-Kyung;Kim, Baeck-Oon;Kim, Nam-Yong
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.15 no.2 s.40
    • /
    • pp.15-23
    • /
    • 2007
  • This paper presents a shoreline change analysis on a reclaimed land, using a pair of aerial photographs taken before and after the reclamation. Shorelines that are defined by a tide datum, i.e. Approximately Highest High Water Level, were mapped by both analytical and digital photogrammetric methods. The past shorelines were overlapped with digital cadastral map from which areas of retracted and protruded lands were computed. Magnitude of shoreline changes was estimated by calculating areas between the past and present shorelines. Comparisons in terms of areas showed a fairly good agreement between the two methods. However, particularly in the estuary of complex morphology, shoreline mapping by digital photogrammetric method requires images to be scanned at a resolution higher than 1200 dpi.

  • PDF