1. A method for creating an appearance model of an object, comprising: receiving an image of an object; identifying a parameter for describing the object; creating a hierarchical appearance model of the object from the image of the object, the hierarchical appearance model having a plurality of layers, each layer including one or more nodes, wherein the nodes in each layer contain information of the object with a corresponding level of detail, and wherein the nodes in different layers of the hierarchical appearance model correspond to different levels of detail; and for each node of the hierarchical appearance model, generating a histogram of the image of the object using the parameter, wherein the histogram includes a plurality of bins, and bin width corresponds to the level of detail of the node.