1. A method, comprising: identifying geographic locations of training images; identifying weather information for each of the identified geographic locations; generating image pairs from the training images; for each image pair of the image pairs, determining whether images of the image pair include the same person; and generating network parameters for a neural network with the identified geographic locations, the weather information for each of the identified geographic locations, and the determination of whether the images of the image pairs include the same person, wherein the identified geographic locations, identified weather information, and determination of whether the images of the image pair include the same person are obtained without human annotation.