Litchi three-dimensional phenotype measurement method based on neural radiation field

The invention discloses a litchi three-dimensional phenotype measurement method based on a neural radiation field, and the method comprises the following steps: S1, shooting an image or video of a litchi fruit through a cellphone, making a two-dimensional image set, and marking the image; s2, acquiring marked image key points by using a COLMAP technology, finding corresponding points among a plurality of images, and estimating the position and direction of a camera by using the points; s3, training the marked image set by using a NeRF network improved based on a ray advancing technology and a tensor radiation field to obtain a three-dimensional implicit representation model; s4, generating a three-dimensional display expression mode grid model by using the volume density, the color, the light and the three-dimensional implicit scene, and judging and screening abnormal points to obtain point cloud data of the litchi fruits; and S5, measuring phenotypic parameters of the litchis according to the point cloud dat