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A new approach to tunnel image acquisition using a fisheye lens camera

In this study, an improved method of acquiring images of tunnels using a fisheye lens is presented. First, a forward image of the inside of a tunnel is obtained using a fisheye lens camera. A portion of this image is then transformed to a rectangular image using a coordinate transformation. To verify this proposed method, the technique was applied to images of an actual tunnel under construction. Although the transformed images obtained in this test were distorted, it is possible to improve the applicability of this method by correcting such distortions.