This paper presents a simple and efficient image processing method for estimating the number of coconut trees in the Tonga region using very high spatial resolution data (30 cm) in the blue, green, red and near infrared spectral bands acquired by the WorldView-3 sensor. The method is based on the detection of tree shadows and the further analysis to reject false detection using geometrical properties of the derived segments. The algorithm is evaluated by comparing coconut tree counts derived by an expert through photo-interpretation over 57 randomly distributed (4% sampling rate) segments of 200 m × 200 m over the Vaini region of the Tongatapu island. The number of detected trees agreed within 5% versus validation data. The proposed method was also evaluated over the whole Tonga archipelago by comparing satellite-derived estimates to the 2015 agricultural census data—the total tree counts for both Tonga and Tongatapu agreed within 3%.

中文翻译：

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使用非常高分辨率的WorldView-3数据对汤加的椰子树进行遥感

本文提出了一种简单有效的图像处理方法，该方法使用WorldView-3传感器获取的蓝色，绿色，红色和近红外光谱带中非常高的空间分辨率数据（30厘米）来估算汤加地区的椰子树数量。该方法基于树木阴影的检测和进一步的分析，以使用派生线段的几何特性拒绝错误检测。通过比较专家通过光解法在汤加塔普岛Vaini区域上的57个200 m×200 m随机分布（4％采样率）段上的椰子树计数来评估该算法。与验证数据相比，检测到的树木数量在5％以内。