How important is the pre-emphasis stage in MFCC?

1. Why do we need pre-emphasis?
2. What does pre-emphasis filter do?
3. What is pre-emphasis in speech recognition?
4. How does pre-emphasis work?

Why do we need pre-emphasis?

Pre-emphasis should be used when the signal loss in the transmission channel between Transmitter and Receiver is heavy and the signal observed at the end of Receiver is less than the receiving sensitivity required for Receiver.

What does pre-emphasis filter do?

Pre-emphasis works by boosting the high-frequency portion of the signal. This compensates for the high-frequency loss in the cable. De-emphasis works by cutting the low-frequency portion of the signal. This may be coupled with an increased transmit voltage.

What is pre-emphasis in speech recognition?

Typically, prior to some process, such as transmission over cable, or recording to phonograph record or tape, the input frequency range most susceptible to noise is boosted. This is referred to as "pre-emphasis" – before the process the signal will undergo.

How does pre-emphasis work?

Pre-emphasis is a way to boost only the signal's high-frequency components, while leaving the low-frequency components in their original state. Pre-emphasis operates by boosting the high-frequency energy every time a transition in the data occurs. The data edges contain the signal's high-frequency content.