HLC (Highlight compensation)

[ermac]

I have noticed with HLC on, super bright areas or light sources in the scene get blacked out (for example car headlights that are blacked out), however I have seen footage where HLC does not do this, it simply dims the light source in the scene. Is this possible to adjust to achieve this?

 

[frmc]

What camera and firmware are you using? All of my cameras just bring exposure down when for example car headlights appear in the scene. I use HLC at 70% setting at winter time here in Finland since it is basically dark 24/7 and with that I can read license plates clearly (brings exposure down and makes license plate readable). Since it is now summertime and sun doesn't set at all so I can't test if any of the new firmwares has changed how HLC works..

 

[ermac]

All of my cameras just bring exposure down when for example car headlights appear in the scene

That's exactly what I would like it to do. I've tried adjusting the HLC setting either up or down, the bright areas are still blacked out, but either get just bigger or smaller.

This is the camera I am using: https://www.dahuasecurity.com/products/productDetail/6301

I don't think I can update the camera's firmware as it's HDCVI and this function is not possible through the DVR.

HLC capability should produce the same desired results though regardless if it is a Dahua IP or HDCVI camera, I have seen cheaper cameras achieve this.

 

[bigredfish]

yeah, the HLC setting doesnt seem to work worth a damn on the CVI cams...my 3231's are the same. If you are trying to use that cam for LPR, you'll get reasonably good results taking the Exposure and Gain way down to like 1, and leaving Low Motion Blur on, setting that down well below 33ms, try 20 or so to start.

 

[ermac]

Thanks bigred, that's disappointing on the 3231's - that is more like highlight masking as opposed to highlight compensation. Will see what I can do with the exposure and gain settings.

 

[Pmedicj]

There is a setting in the web GUI that allows you to adjust the sensitivity for HLC, WDR, BLC etc.