Leaf area measuring method based on lasers and images

Abstract

The invention discloses a leaf area measuring method based on lasers and images. The leaf area measuring method includes the steps that the number (n) of pixel points of a digital camera is preset; a standard board is used, wherein the length-width ratio of the standard board is the same as the length-width ratio of a screen of the digital camera, and when the shooting range of the digital camera covers the standard board, a laser range finder is used for measuring the distance between the standard board and a lens of the digital camera; when the shooting range of the digital camera is enabled to cover a leaf on a leaf clip, the laser range finder is used for measuring the distance between the leaf clip and the lens of the digital camera, and a photo is shot; according to data acquired from the above steps, the area of a shot image containing the leaf is calculated; and the area of the leaf is obtained according to the area represented by each pixel, and the number of the pixels of the leaf after image processing. According to the leaf area measuring method, based on the optical imaging principle, the laser range finder and the standard board are adopted in the leaf area measuring method, and therefore the detection accuracy and the detection speed of the area of the leaf are improved.

Description

technical field [0001] The invention belongs to the field of measurement of crop growth information in a greenhouse environment, and relates to a measurement method based on laser light and images. Background technique [0002] The crop leaf area parameter is an important crop growth parameter, which can be used to calculate the water consumption, transpiration and yield of the crop, so the leaf area parameter can be used to analyze the growth status of the plant, establish a plant growth model, and further grasp the plant leaf area. It has positive significance for guiding production and formulating technical measures for high-yield, high-quality and high-efficiency cultivation. At present, the leaf area measurement methods mainly include leaf weighing method, grid method, regression equation method, leaf area meter method, digital image method and so on. The weighing method and grid method have higher measurement accuracy, but the leaves need to be picked and weighed, whi...

AI Technical Summary

Problems solved by technology

The system-based calibration measurement method requires that the system must be calibrated before measurement, and the system needs to be re-calibrated when the measurement environment changes. However, this method has high measurement accuracy, but lacks flexibility and practicability.

The calibration measurement method based on the reference object is simple, convenient, and flexible to operate, but the requirements for the reference object are strict, and the area of ​​the reference object directly affects the measured value of the leaf area.

Generally, to determine the area of ​​the object to be photographed needs to be calculated by the focal length, but ordinary digital cameras cannot intuitively know the focal length and field of view. It is necessary to scan the photos into the computer first, and then use special software to judge the focal length of each photo.

While ordinary digital cameras are relatively cheap in price, digital cameras that can intuitively see the focal length are relatively expensive

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