Noise Cancellation
Definition
Techniques for reducing or eliminating unwanted background sounds from an audio signal.
Noise cancellation in the context of speech processing refers to digital signal processing techniques that separate speech from background noise. Spectral subtraction, Wiener filtering, and neural network-based approaches can identify and attenuate noise while preserving the speech signal.
Modern speech recognition models like Whisper are trained on noisy data and are somewhat robust to background noise. However, preprocessing with noise cancellation still improves accuracy, especially in challenging environments. Active noise cancellation in hardware (headphones/microphones) works differently, using inverse sound waves to cancel ambient noise before it reaches the digital signal.