Originally featured on BroadcastEngineering.com
4/22/2009 6:21 AM
How many times have you had to reach for the volume button because someone overly compressed a commercial or failed to properly ride gain on a program? With the Evertz Intelligain, variations in loudness between programs and commercials or between channels, are over.
IntelliGain calculates the perceived loudness of the input audio and modifies the audio to ensure that the long-term average loudness level is at the target level. IntelliGain works with mono, stereo and multi-channel audio per program and can handle up to 8 programs simultaneously. The objective loudness calculation is based on ITU Recommendation (ITU-RBS.1770), "Algorithms to measure audio program loudness and true-peak audio level”. This recommendation provides equations for calculating loudness over mono, stereo and multichannel audio programs.
The Evertz solution constantly calculates audio program loudness. When the loudness is over the target level, it reduces the gain; and when the loudness is below the target level, it increases the gain. The gain adjustment smoothness is user-controllable by setting attack and release times. IntelliGain is available on many Evertz products.