Method and system for tracking a state of a camera

Abstract

The invention relates to a method for determining a state x() of a camera () at a time t, the state x() being a realization of a state random variable X, wherein the state is related to a state-space model of a movement of the camera (). The method comprises the following steps: a) receiving an image () of a scene of interest () in an indoor environment () captured by the camera () at the time t, wherein the indoor environment () comprises N landmarks () having known positions and orientations in a world coordinate system (), N being a natural number; b) receiving a state estimate Formula I () of the camera () at the time t, wherein the state estimate () comprises an estimate of the pose of the camera; c) determining () positions of M features in the image (), M being a natural number; and d) determining () the state x() of the camera () at the time tbased on (i) observation zat the time t, the observation zbeing a realization of a joint observation random variable z, the observation zcomprising the positions of the M features and data indicative of distance between each of the M features and its corresponding object point in the scene of interest, respectively, and (ii) the state estimate Formula {circumflex over ( )}I (), wherein the determining () of the state x() comprises determining () an injective mapping estimate from at least a subset of the M features into the set of the N landmarks (), and wherein the determining () of the state x() is based on an observation model set up () based on the determined injective mapping estimate. The invention also relates to a computer program product and to an assembly.