数字图像处理技术在叶面积测量中的应用

传统测量叶面积方法费时、低效,叶面积仪法高成本、维修不便。本研究利用图像处理技术测量叶面积,从解决图像阈值的分割、叶片阴影去除以及叶片边缘检测算法等问题出发,应用大津法求得阈值,中值滤波法去除杂点,采用Roberts算子检测边缘,进而计算叶面积。叶面积仪法与图像处理法比较叶面积值相关系数R²为0.962,剪纸法与图像处理法比较叶面积值相关系数R²为0.949,最后验证本方法适合大量叶面积的测量工作,且具有速度快、数据准确、精度高的特点。

Leaf Area Measurement System Based on Digital Image Processing Technology

In view of the time consuming and low efficiency of the traditional method of leaf area measurement, and the high cost and inconvenient maintenance of the leaf area meter method, this study used the image processing technology to measure the leaf area. The computer vision technology reference method was used to solve the limitations of image threshold segmentation, leaf shadow removal and leaf edge detection algorithm, and the threshold was obtained by OTSU method, the median filtering method was used to remove residual impurities in the image, and the Roberts operator was used for edge extraction. Leaf areas are calculated and compared with those obtained by leaf area meter and paper-cutting method. The leaf area determined by the leaf area meter method and the image processing method had the correlation coefficient R² of 0.962, and the leaf area determined by the paper cutting method and the image processing method had the correlation coefficient R² of 0.949. The digital image processing method is validated to be suitable for large amount of leaf area measurement, and has fast speed, accurate data and high precision.