1. A method for real-time tracking of features, the method comprising: acquiring a collection of images and one or more subsequent collections of images to create a three-dimensional space, wherein the collection of images is composed of a first plurality of images captured substantially simultaneously from multiple sources and the one or more subsequent collections of images are composed of a second plurality of images captured substantially simultaneously from the multiple sources, and wherein the second plurality of images are captured later in time than the first plurality of images; extracting features in each image among the first plurality of images, wherein each feature is a region of multiple pixels within the corresponding image, each region having a feature descriptor vector describing the region; applying a refinement routine to each feature descriptor vector to identify sub-features indicative of a prominent point within each feature, wherein when a sub-feature cannot be identified within a feature descriptor vector, the corresponding feature is deleted; identifying a candidate feature in the three-dimensional space for tracking; and tracking the candidate feature in the three-dimensional space over time using the sub-features within the second plurality of images, wherein the tracked candidate feature is used to determine a travelled path of the multiple sources.