7847FSEDA Series
Frame Synchronizer and Distribution Amplifier
Revision 0.1
Page - 47
5.2.14. IntelliGain
®
[+IG2]
IntelliGain
®
is a technology developed by Evertz to control the loudness of audio programs on the fly.
More specifically, it 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 16 programs simultaneously. The
objective loudness calculation is based on ITU Recommendation (ITU-R BS.1770-3), “Algorithms to
measure audio program loudness and true-peak audio level”. This recommendation provides equations
for calculating loudness over mono, stereo and multi-channel audio programs. IntelliGain
®
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.
The IntelliGain
®
audio processing module is an
optional product feature
, and requires the IntelliGain
®
product option
[+IG2]
to be included in the module’s product string. This feature is an upgradeable
product option, and can be purchased and added to 7847FSEDA modules that do not currently have
this product option. The
[+IG2]
product option includes a dedicated 16 channel IntelliGain
®
audio
processing module for each video processing path.
Features:
•
Normalize loudness of audio programs to a target level
•
Supports up to 16 programs and 16 channels (
per video path
)
•
Relatively constant gain within a program interval to preserve audio dynamic range
•
Simultaneously process multiple multi-channel programs
•
User adjustable attack and release times
•
Loudness algorithm based on ITU-R BS. 1770-3
•
Peak limiting
•
LKFS calculations
•
Momentary, short term and integrated loudness measurements
5.2.14.1. IntelliGain
®
Mixer [+IG2]
The IntelliGain
®
Mixer tab contains controls for audio routing, audio gain, and audio inversion for the
IntelliGain
®
audio processing module input channels. Each IntelliGain
®
input audio channel mixer
consists of two independently selectable sources (X & Y) with each source having its own gain and
inversion controls. The selectable sources for the IntelliGain
®
audio mixers may vary based on the
audio options enabled on the module. Table 5-6 lists all the selectable sources for the IntelliGain
®
audio
mixers, and which sources are enabled by product options. Figure 5-21 illustrates the layout of these
controls in the VistaLINK® PRO configuration view.
NOTE:
Please contact Evertz if interested in adding the IntelliGain
®
[+IG2] product option.
NOTE:
The IntelliGain
®
Mixer tab is only visible when [+IG2] is included in the module’s
product string.
