Pre-emphasizing in speech recognition

1. What is pre-emphasis in speech recognition?
2. What is meant by pre-emphasis?
3. What does pre-emphasis filter do?
4. What is speech pre processing?

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.

What is meant by pre-emphasis?

pre·​emphasis. (ˈ)prē+ : the intentional alteration of the relative strengths of signals at different frequencies (as in radio and in disc recording) to reduce adverse effects (as noise) in the following parts of the system.

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 speech pre processing?

Speech signal preprocessing is the first and the most important step in the automatic speech recognition process. The preprocessing of speech consists of cleaning the speech signal from ambient and undesirable noises, detecting speech activity, and normalizing the length of the vocal tract.