... considerable success in the ASRdomain. The basic principle of NMF-based audio processing,as will be explained in detail in Section 2, is to find a locallyoptimal factorization of a spectrogram into ... a variety of applications incorporating speech interfaces forhuman-machine communication, i ncluding human-robotinteraction, dialog systems, voice command applications,and computer games. In ... 2.WhilethePCA basis could be estimated class-wisely, in analogy toNMF (6), we used all available training instances for thecomputation of t he principal components, as this guaranteespairwisely...