1. A computer-implemented method for flexible matching with combinational similarity, comprising: receiving an object image; receiving a query image including one or more pixels; comparing the query image with the object image; determining one or more matching information based upon combinational similarity, the combinational similarity being a combination of one or more similarity arrays created by comparing one or more gradient histogram information associated with the object image to the one or more gradient histogram information associated with the query image; and presenting the one or more matching information to a user.