Patent ID: 9288602
Filing Date: 2016-03-15
CPC Classification: H04S

Claim Text:
1. A stereo extension apparatus comprising: a database that stores predetermined information as a result of Gaussian mixture model (GMM) training or hidden Markov model (HMM) training; a modified discrete cosine transform (MDCT) transformer that transforms a mono signal through MDCT; a feature parameter extractor that extracts a feature parameter of the mono signal from an MDCT coefficient output from the MDCT transformer; a side signal energy estimator that estimates subband energy of a side signal with reference to information stored in the database based on the feature parameter; an energy controller that obtains the MDCT coefficient of a side signal estimated from the subband energy of the estimated side signal; an inverse MDCT transformer that obtains an estimated side signal by transforming the MDCT coefficient of the estimated side signal through inverse MDCT; and a stereo signal generator that obtains a stereo signal based on sum and difference between the mono signal and the estimated side signal.