Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography (한국측량학회지)

Korean Society of Surveying, Geodesy, Photogrammetry and Cartography (한국측량학회)
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Edge Response Analysis of UAV-Images Using a Slanted Target

경사 타겟을 이용한 무인항공영상의 경계반응 분석

  • Received : 2020.07.17
  • Accepted : 2020.08.20
  • Published : 2020.08.31
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Abstract

UAV (Unmanned Aerial Vehicle) photogrammetry has recently emerged as a means of obtaining highly precise and rapid spatial information due to its cost-effectiveness and high efficiency. However, current procedures or regulations for quantitative quality verification methods and certification processes for UAV-images are insufficient. In addition, the current verification method for image quality is not evaluated by an MTF (Modulation Transfer Function) analysis or edge response analysis, which can analyze the degree of contrast including image resolution, and only relies on the GSD (Ground Sample Distance) analysis. Therefore, in this study, the edge response analysis using a Slanted edge target was performed along with GSD analysis to confirm the necessity of analyzing edge response analysis in UAV-images quality analysis. Furthermore, a Matlab GUI-based software tool was developed to help streamline the edge response analysis. As a result, we confirmed the need for edge response analysis since the outputs of the edge response analysis from the same GSD had significantly different outcomes. Additionally, we found that the quality of the edge response analysis of UAV-images is proportional to the performance of the camera mounted on the UAV.

무인항공사진측량은 저비용, 고효율의 장점으로 최근 고정밀의 신속 공간정보 데이터 취득 수단으로 떠오르고 있다. 하지만 무인항공영상의 정량적인 품질 검증 방법이나 인증에 대한 구체적인 절차와 세부규정이 미흡하다. 또한, 영상 품질에 대한 검증 수단이 영상의 해상도와 함께 명암의 대비 정도를 분석 할 수 있는 MTF (Modulation Transfer Function) 분석이나 경계반응 분석이 아니라 단순히 GSD (Ground Sample Distance) 만으로 품질을 평가하는 실정이다. 이에 본 연구에서는 무인항공영상 품질 분석에서 경계반응 분석의 필요성을 확인하기 위해 GSD 분석과 함께 Slanted edge target을 이용한 경계반응 분석을 실시하였다. 또한, 작업자가 간편하게 경계반응을 분석할 수 있도록 Matlab GUI 기반 tool을 제작하였다. 연구 결과, 동일한 GSD 임에도 불구하고 경계 반응 분석 결과는 상이하게 나타나 경계반응 분석의 필요성을 확인할 수 있었다. 아울러, 무인항공영상의 경계반응 분석 수치는 무인항공기에 탑재한 카메라의 성능에 비례함을 알 수 있었다.

Keywords

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