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An Implementation of Smart E-Calipers for Mobile Phones

모바일 폰을 이용한 스마트 E-캘리퍼스 구현

  • Yun, Han-Kyung (School of Computer Science and Engineering, Korea University of Technology and Education)
  • Received : 2020.07.29
  • Accepted : 2020.08.23
  • Published : 2020.10.30

Abstract

The study is underway with the goal of developing an app that will replace vernier calipers using a smartphone's high-performance camera. The specifications of the camera mounted on recent smart phones have evolved so that usually has a 12 Mpixels of image sensor and its size of the pixel is 1.4㎛ and the size of the image sensor is 1 / 2.55 in. The proposed algorithm will apply to develop a precision measuring application that will compete with the Vernier calipers. Most existing applications cannot guarantee an accuracy in scale because the scale of the ruler displayed on the image is unclear or the size of the measurement object varies depending on the distance between the camera and the measurement object. In addition, another accurate measuring tools using lasers are also available, but they are limited because they are expensive. Therefore, if easy-to-carry and precise applications are developed, it is possible to substitute existing measurement tools. The proposed correction algorithm is an algorithm that automatically corrects the distorted source image using the shape and size information of the known template. The e-calipers are applications that display the distance when the area to be measured is specified in the corrected image.

스마트폰의 고성능 카메라를 사용하여 버니어 캘리퍼스를 대체할 앱의 개발을 목표로 연구를 진행하고 있다. 앱은 제안된 템플릿이 부착된 측정 대상을 촬영한다. 촬영된 영상에서 템플릿을 참조하여 측정 대상에서 사용자가 지정한 지점 간의 거리를 측정한다. 앱의 정밀도는 시중에서 판매되고 있는 버니어 캘리퍼스의 오차 범위를 유지하도록 한다. 시장에 보급된 스마트폰의 카메라는 12M 픽셀이며, 그 이미지 셀의 크기는 1.4㎛이므로 이론적으로 버니어 캘리퍼스보다 더 정밀한 측정이 가능하다. 기존에 제안한 알고리즘에서는 촬영된 소스 영상의 템플릿 형태로부터 기준 거리를 추출하였지만, 제안하는 알고리즘은 알고 있는 템플릿의 기하학적 속성을 이용하여 영상을 보정한 후 거리를 구함으로써 향상된 정밀한 길이를 구할 수 있다.

Keywords

References

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