| Stage | Technology or method | Literature |
| Preprocessing | LPF | [17ā20] | BWF | [13, 21, 22] | FD and SD | [17, 23] | LPF, FD, and SD | [24] | FIR, FD, and SD | [14, 25, 26] | PD | [27] | Sliding window | [28] |
| Feature extraction | TDF | [14, 19, 23ā25, 27, 29] | TDF and FDF | [26] | DWT | [18] | CWT | [21] | LDA | [27] | TDF and KLT | [22] | SCW, FDF, and TDF | [20] | Sparse softmax vector | [28] |
| Matching or classification | k-NN | [14, 18, 23] | k-NN and MV | [27] | LDC | [25] | SVM | [18, 26] | BN and k-NN | [24] | PearsD | [21] | Manhattan distance and Euclidean distance | [22] | BN, NB, RBF, and MLP | [19] | DCT | [30] | SVM, GBT, and IsFrst | [20] | k-NN, NB, RF, and LDC | [28] |
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