The signals in this page demonstrate the performance of polya urn base bandwidth expansion. The algorithm represents spectrograms as the output of draws from a mixture mutinomial. The possible outcome of any draw from the mixture multinomial is a single frequency. The multinomial components are learned from broadband training data. Narrow-band spectrograms are modelled as draws from the mixture, where some outcomes (corresponding to high frequencies) have been obscured. The obscured entries are estimated.
| Bandlimited to telephone bandwidth, expanded to 8Khz | Fullband Signal | Bandlimited signal | Reconstructed signal |
| Fullband Signal | Bandlimited signal | Reconstructed signal | |
| Fullband Signal | Bandlimited signal | Reconstructed signal |