Table 2. Speech features for accent classification.
| Reference | Feature | Type | Description |
|---|---|---|---|
| Rajpal et al. (2016) | Filter-Bank | Short-term spectral | Total energies in spectral filter applied on mel-scale |
| Shon, Ali & Glass (2018) | Log Filter-Bank | Short-term spectral | Logarithmic magnitude of Filter-Bank energies |
| Singh, Pillay & Jembere (2020) | MFCC | Short-term cepstral | Discrete cosine transform of Log Filter-Bank |
| Rajpal et al. (2016) | PLPC | Short-term cepstral | All-pole autoregressive modelling of Log Filter-Bank |
| Babu Kalluri et al (2020) | Functional vector | Long-term statistical | Statistical functions for short-term features |
| Campbell et al. (2006) | GMM super vector | Long-term parametric | Parameters of UB-GMM model for short-term features |
| Dehak et al. (2011) | I-vector | Long-term parametric | Factorization of GMM supervector |
| Snyder et al. (2018) | X-vectors | Neural network | Neural network bottleneck representation |
| Shon et al. (2017) | AE embedding | Neural network | Unsupervised representation learning |
| Brown & Wormald (2017) | ACC-DIST | Phonotactic | Distance matrix between phoneme acoustics |
| Najafian & Russell (2020) | PPRLM | Phonotactic | Sequence and frequency of phoneme usage |