20. The computer-readable storage device of claim 17 , containing instructions that when executed cause one or more processors to define a second video feature within a short-term difference image or a long-term difference image calculated based on the image of the video input.
17. A computer-readable storage device containing instructions that when executed cause one or more processors to: identify a pool of features from multiple types of input, the pool of features comprising a first video feature from a video input, the first video feature comprising a parent rectangle within a feature rectangle in an image of the video input; calculate a numeric value associated with the first video feature by summing values of pixels in the parent rectangle; and generate a classifier for speaker detection using a learning algorithm wherein nodes of the classifier are selected using the pool of features, based on the numeric value associated with the first video feature.