Abstract: A computer-implemented method of determining the location of a mobile device comprising a camera and at least one inertial sensor. A sequence of images are captured over a period of time, and a first neural network determines features indicative of the motion of the device from pairs of consecutive images. Data indicative of the motion of the device is captured, and a second neural network determines features indicative of the motion of the device from the data. A third neural network then determines features indicative of the location of the device from the features determined by the first neural network and the second neural network. The location of the device is the determined from the features determined by the third neural network.

Abstract: A computer-implemented method of determining the location of a mobile device comprising a camera. The method comprises the steps of capturing, using the camera, a sequence of images over a period of time; for pairs of consecutive images from the sequence of images, determining, using a first neural network, features indicative of the motion of the device between the time the first image of the pair of images was captured and the time the second image of the pair of images was captured; for a sequence of consecutive images, determining, using a second neural network, features indicative of the location of the device from the features determined by the first neural network; and for a sequence of consecutive images, determining the location of the device from the features determined by the second neural network.

Abstract: A method of determining the position of a mobile device uses a model. The model is constructed by obtaining a map of a geographical area, constructing the graph using the map, wherein vertices of the graph correspond to areas of the map, and two vertices are joined by an edge when the areas corresponding to the vertices are adjacent and can be travelled between by a device, and building the one or more feature functions using the graph, wherein a feature value of the one or more feature functions indicates the extent to which the observations support the device being positioned in the areas corresponding to one or more vertices of the graph.