Method and device for calculating irrigation water demand of farmland

The invention provides a farmland irrigation water demand calculation method and device, and belongs to the technical field of agricultural information, and the method comprises the steps: carrying out the image segmentation of a target image of a farmland according to color features, and determining a target region where a green crop is located in the target image; determining the coverage rate of the green crops according to the ratio of the number of pixels in the target area to the total number of pixels in the target image; and determining the irrigation water demand of the farmland according to the coverage rate and the meteorological data. According to the method, the crop coverage rate is calculated by using the image segmentation method based on color features, the crop coefficient is calculated, and the crop water demand is calculated according to the crop coefficient and the reference crop evapotranspiration, so that a traditional crop water demand calculation mode is changed, automatic calculation