2.4 Brief Overviews of Various other Stages in the System
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dimensional problem, the classes are now separable.
Scatter Plot for GMM−MFCC/GMM−IMFCC scores −500 = True Speaker = Anti−Speakers
Log Liklihood scores of GMM for IMFCC →
−1000
−1500
−2000
−2500
−3000
−3500 −4000
−3500
−3000 −2500 −2000 Log Liklihood scores of GMM using MFCC →
−1500
−1000
Figure 2.8: Scatter plot for feature diversity [Note: Each point in the plot represents an utterance]
Different levels of fusion strategies will be described in chapter 5, where the fused system developed from MFCC and IMFCC feature sets performs better than the system developed from MFCC. Note that this complementary information is missing in a linearly spaced filter bank structure (its corresponding cepstral parameters are known Linear Frequency Cepstral Coefficients (LFCC) [5]) because the inversion of the linearly spaced filter bank will be linearly spaced again.
2.4
Brief Overviews of Various other Stages in the System
This section reviews briefly the pre-processing and modeling stages that have been adopted in this work. Note that the specifications in the two stages will remain the same for all the works presented in the thesis. The stages are described next.