What is a 'notch' in image processing?

1. What is notch filter in image processing?
2. What is a notch filter and in what products is it commonly found?
3. What is notch in EQ?

What is notch filter in image processing?

A notch filter is a type of band-stop filter, which is a filter that attenuates frequencies within a specific range while passing all other frequencies unaltered. For a notch filter, this range of frequencies is very narrow. The range of frequencies that a band-stop filter attenuates is called the stopband.

What is a notch filter and in what products is it commonly found?

Narrow notch filters (optical) are used in Raman spectroscopy, live sound reproduction (public address systems, or PA systems) and in instrument amplifiers (especially amplifiers or preamplifiers for acoustic instruments such as acoustic guitar, mandolin, bass instrument amplifier, etc.) to reduce or prevent audio ...

What is notch in EQ?

A word used to describe a very narrow band of frequencies to be cut by an equalizer. When an EQ circuit has a very high Q (narrow bandwidth) it is sometimes referred to as a notch filter.