Assessment of Low-Cost Digital Camera with Fisheye Lens in Close-Range Photogrammetry for Indoor Building Dimensional Measurement

Abstract

This paper examines the potential of using Samsung Gear 360, a low-cost consumer-grade spherical camera for indoor building dimensional measurement. The aims and objectives of this experiment are to assess the metric precision and accuracy level of detail that can be achieved from the Samsung Gear 360’s fisheye lens coupled with digital modeling techniques based on close-range photogrammetry algorithms. Initial results indicated that the metric accuracy was relatively low while using the projection created directly from the mobile phone or even using the Gear 360 Action Direction desktop software for post-processing. To address this discrepancy, this paper proposed an alternative solution that was devised, involving the generation of equirectangular projections to resolve the inconsistency of accuracy caused by the original fisheye photos. For this, a calibration process was performed to gain insights into the intrinsic parameters of the two lenses of the camera and their relative orientation. As a result, new equirectangular projections were produced, leading to a significant enhancement in geometric accuracy. In conclusion, the study has demonstrated that the close-range photogrammetric technique with low-cost consumer-grade digital cameras has the potential for indoor building dimension measurement from spherical photographic panoramas to support strata surveying tasks in cadastral.