應用魚眼鏡頭物像對應模式於雨量計顯露度測量
Other Title
Applying Fisheye Object-Image Correspondence in Rain Gauge Exposure Measurement
Journal
航測及遙測學刊
Journal Volume
30
Journal Issue
2
Start Page
85
End Page
107
ISSN
1021-8661
Date Issued
2025-06
Author(s)
彭綿聿
Abstract
雨量計的運作受環境遮蔽程度影響，過度遮蔽可能導致降雨量測量偏差，為確保測量成果的代表性，雨量計應架設於開闊場域，並持續監測其遮蔽情形，針對此需求，本研究提出基於影像的演算法，以估計雨量計之環境顯露度。透過魚眼鏡頭拍攝雨量計上方的對空影像，套用魚眼鏡頭物像對應模式，並依據顯露度幾何條件定義參數，擬定傾斜誤差改正方法。實驗結果顯示，本研究所研擬之方法應用於顯露度測量，在方便野外的施作程序及考量各類誤差的修正模式下，可提供仰角誤差小於1度之測量品質，滿足顯露度測量之精度需求。
The operation of rain gauges is influenced by environmental shielding, where excessive obstruction may lead to precipitation measurement biases. To ensure the representativeness of measurement results, rain gauges should be installed in open areas, and their obstruction conditions should be continuously monitored. To address this need, this study proposes an image-based algorithm to estimate the rain gauge exposure. Through capturing sky images above the rain gauge using a fisheye lens and applying the fisheye object-image correspondence, and then defines parameters based on exposure geometric conditions and devises a tilt error correction method. Experimental results demonstrate that, in a correction mode that is convenient for field application procedures and takes into account various errors, the proposed method for exposure measurement can achieve an elevation angle accuracy within 1 degree, meeting the quality requirements of exposure measurement.
Subjects
魚眼鏡頭
物像對應
雨量計
顯露度測量
傾斜誤差改正
Fisheye Lens
Object-Image Correspondence
Rain Gauge
Exposure Measurement
Tilt Error Correction
Type
journal article