Estimating Rice LAI Based on Digital Camera and Image Processing


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A fast, low-cost method for rice canopy leaf area index (LAI) estimation is proposed. Take photos of rice canopy with a 57° view angle from above using a common digital camera. Extract canopy gap fraction by digital image processing technology. Then LAI can be estimated using canopy gap fraction based on optical transmission model and Leaf angle distribution model. AccuPAR-LP80 and direct measurement were employed to provide Comparative data. Comparison of the three methods, we obtained high correlation coefficients (R²≥0.6). The result shows that the method is especially suitable for estimating LAI in early growth stage of rice.



Edited by:

David Wang




G. Y. Pan et al., "Estimating Rice LAI Based on Digital Camera and Image Processing", Key Engineering Materials, Vol. 500, pp. 586-591, 2012

Online since:

January 2012




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