1. A method for processing an image of a scene, the method comprising: receiving the image; processing the image to determine one or more characteristics of the scene, wherein processing the image to determine the one or more characteristics of the scene comprises: determining that the image includes a shadow by: calculating a number of pixels associated with a group of pixels determined to be invalid; and matching the number of pixels associated with the group of pixels determined to be invalid to a stored number of invalid pixels determined to indicate the shadow; and estimating one or more values for the pixels associated with the group of pixels determined to be invalid; and detecting a portion of the image associated with a floor by at least: scanning at least a portion of the image to fit a plurality of lines to depth values; starting with a line of the plurality of lines closest to a bottom of the image and then moving upwards, determining whether each line has a slope that defines an angle or change that is greater than a threshold until one of the lines is determined to have a slope that defines an angle or change that is greater than the threshold; and determining that the portion of the image associated with the floor corresponds to each line determined to have a slope that defines an angle or change not greater than the threshold; and rendering a refined image based on the one or more characteristics of the scene.