Subscriber Discussion

What Is The Disadvantage Of Capping Automatic Gain Control?

UD
Undisclosed Distributor #1
Oct 11, 2016

what is the disadvantage of CAPPING the Automatic gain control

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Cameron Javdani
Oct 11, 2016
Louroe Electronics

Do you mean as in capping the gain or capping the functionality of AGC? Capping the gain will reduce the mic saturating. This usually happens when someone yells very closely to a mic or is too close to the mic. The sound can clip or become garbled.

The disadvantage of running AGC is that you'll miss higher end frequencies. These are especially crucial running sound analytics. Whether to use AGC or not depends on what types of sounds you're trying to pick up.

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Cameron Javdani
Oct 11, 2016
Louroe Electronics

Clearly I meant this for audio AGC.

JH
John Honovich
Oct 11, 2016
IPVM

Gain / AGC for Video Surveillance Guide

In low light, capping will typically make the image darker than it would otherwise be, as the gain control is constrained from brightening the image.

In general, you should not cap AGC unless you really know what you are doing and know that this will not hurt image quality. One reason an advanced user might do this is because they care more about eliminating on screen noise than they do about making the image darker.

U
Undisclosed #2
Oct 11, 2016
IPVMU Certified

One reason an advanced user might do this is because they care more about eliminating on screen noise than they do about making the image darker.

Or about image blurring due to a compensatory slow(er) shutter.

JH
John Honovich
Oct 11, 2016
IPVM

Well, an advanced user would control the shutter speed / range directly, not relying on indirect impacts from other settings.

U
Undisclosed #2
Oct 12, 2016
IPVMU Certified

Agree, that's what I'm talking about as well, i.e.

If an advanced user if cared about eliminating screen noise AND didn't want to make the image darker, one option would be to make the shutter slower. As long as any blurring was an acceptable trade-off.

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