1. A method for generating an embedding for a signal, which is invariant to an operator, comprising steps: measuring the signal with each vector from a set of measurement vectors to produce a corresponding set of coefficients, wherein the measuring compares and transforms each measurement vector and the signal using the operator; selecting a set of one or more matching coefficients according to predefined criteria; and combining the matching coefficients to produce the embedding for the signal, wherein the embedding is operator invariant and the steps are performed in a processor.