Instantaneous gain & exposure

csJosh

n3wb
May 4, 2023
27
23
United States
Hi All,
Digging in to some Dahua API interfaces, I found one (NET_QUERY_VIDEO_IN_STATUS from the SDK) that I think reports the specific gain & exposure number the camera is currently using. That web UI lets you set a range for gain & exposure, but doesn't tell you what value is currently being used.

The most interesting thing I've noticed so far is that, for my 5442 outdoor cameras, the gain drops to almost 0 within an hour after sunrise on an overcast day.
Seems like gain only kicks in once it gets dark out, which I guess is what you'd expect.
- Josh
 
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Pardon my ignorance....but is it possible to pull info from the api interface into the overlay of the camera using the web interface?

Ie...say i wanted the gain number to show up on the overlay below the time or something like that.

I see a bunch of overlay options but didnt know if you could use api to populate.
 
Pardon my ignorance....but is it possible to pull info from the api interface into the overlay of the camera using the web interface?

Ie...say i wanted the gain number to show up on the overlay below the time or something like that.

I see a bunch of overlay options but didnt know if you could use api to populate.
The web ui gives you the ability to overlay textual messages on the video.
The current gain information I think is only available via the SDK api. Theoretically you could write a script that regularly reads the gain information and then calls an API to update the text overlay to show the current gain.

Or you could stream from the camera, and use a video editing tool (maybe ffmpeg) to add text on top of the stream.
 
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Thats kind of what i was figuring ... needed to use external script and push back to device.

Would be nice if there capability was there to just put some variables into the overlay text box and have the system display it. IE. OVERLAY BOX: %gain%
I guess that would be too easy ;0
 
Pardon my ignorance....but is it possible to pull info from the api interface into the overlay of the camera using the web interface?
Ie...say i wanted the gain number to show up on the overlay below the time or something like that.
I see a bunch of overlay options but didnt know if you could use api to populate.
Yes, there is API you can use for your own solution.

Also the genius @runraid and other contributors have made a Home Assistant Plugin for Dahua cameras.

It uses the Dahua API to change the overlay.
%20Is space character.
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