What is AGC?
Automatic Gain Control is a filter that automatically increases voice gain if it is too low and decreases voice gain if it is too high.
For example AGC filter is built in Skype and other VoIP software to achieve comfort voice gain level of captured and published audio streams.
Automatic gain control (AGC) is a technique found in many electronic devices. The average or peak output signal level is used to adjust the gain to a suitable level, enabling the circuit to work satisfactorily with a greater range of input signal levels. For example, without AGC the sound emitted from an AM radio receiver would vary to an extreme extent from a weak to a strong signal; the AGC effectively reduces the volume if the signal is strong and raises it when it is weaker.
Why the AGC filter is needed for Flash+Wowza application?
Flash Player does not support AGC feature natively.
WZ-AGC is a server-side AGC filter for Wowza Media Server.
You can install WZ-AGC and add AGC filter to your Wowza application.