“…Data-driven speech models, built on the training data of real speech, represent a different 33 way of imposing prior or constraint on the speech to be estimated. Common speech models include 34 vector-quantization (VQ) codebooks (e.g., Naidu and Srinivasan, 2012;Srinivasan et al, 2006), 35 Gaussian mixture models (GMM) (e.g., Kundu et al, 2008), hidden Markov models (HMM) (e.g., 36 Ephraim et al, 1989; Sameti and Deng, 2002;Zhao and Kleijn, 2007), and inventory-based models 37 terms of improved speech recognition and speech enhancement performance.…”