Noise Sensitivity
MFCC values are not very robust in the presence of additive noise, and so it is common to normalise their values in speech recognition systems to lessen the influence of noise. Some researchers propose modifications to the basic MFCC algorithm to improve robustness - e.g. by raising the log-mel-amplitudes to a suitable power (around 2 or 3) before taking the DCT, which reduces the influence of low-energy components.
Read more about this topic: Mel-frequency Cepstrum
Famous quotes containing the words noise and/or sensitivity:
“While we were thus engaged in the twilight, we heard faintly, from far down the stream, what sounded like two strokes of a woodchopper’s axe, echoing dully through the grim solitude.... When we told Joe of this, he exclaimed, “By George, I’ll bet that was a moose! They make a noise like that.” These sounds affected us strangely, and by their very resemblance to a familiar one, where they probably had so different an origin, enhanced the impression of solitude and wildness.”
—Henry David Thoreau (1817–1862)
“What we think of as our sensitivity is only the higher evolution of terror in a poor dumb beast. We suffer for nothing. Our own death wish is our only real tragedy.”
—Mario Puzo (b. 1920)