基于黑白扫描图像的叶面积测量方法

Leaf Area Measurement Method Based on Black-White Scanning Image

【目的】为了快速准确测量叶片面积,探讨一种基于黑白扫描图像的测量方法。【方法】使用平板扫描仪制作叶片黑白二值图像,利用图像处理软件读取图像并统计图像和叶片的总像素,依据扫描成像大小与扫描稿台尺寸等比关系,以及已知的扫描稿台尺寸,计算获取叶片面积;分别使用两个不同品牌型号扫描仪对20张叶片进行测量,以方格纸法测量结果为真值依据进行误差分析,同时采用叶面积仪进行比对验证。【结果】两个扫描仪均方根误差分别为0.90 cm^(2)、0.95 cm^(2),平均相对误差分别为1.06%、1.64%;叶面积仪测量均方根误差为0.62 cm^(2),平均相对误差为0.92%。【结论】扫描仪法与方格纸法和叶面积仪测量结果间均不存在显著差异,基于黑白扫描图像的叶片面积测量方法具有方便快捷、成本低、精度高的应用潜力。

【Objective】In order to measure leaf area quickly and accurately,a measurement method based on black-and-white scanning image is discussed.【Method】The black-white binary image of the leaf was scan with a flat-panel scanner,the image was read by the processing software and counted the total pixels of the image and the leaf.The leaf area was calculated according to the proportional relationship between size of image and scanning platen,and the known scanning platen size.Two brand scanners were used to measure 20 leaves respectively,and the error analysis was carried out based on the measurement results of the checkered-paper method.At the same time,leaf area meter was used for comparison.【Result】The root mean square errors of the two scanners were 0.90 cm^(2) and 0.95 cm^(2),and the average relative errors were 1.06%and 1.64%respectively.The root mean square error of leaf surface meter is 0.62 cm^(2) and the average relative error is 0.92%.【Conclusion】There is no significant difference between the scanner method,the checkered-paper method and the leaf area meter.The method of measuring leaf area based on black-and-white scanning image has the potential of convenience,low cost and high accuracy.