Dahua Bullet Camera for Traffic - which one?

[Marble68]

Hi Andy -

I'm working on a project for my town to capture a photo of every vehicle that passes a sign, day or night.

The road speed limit is 50mph.

Which camera would you recommend we test? Is the motion detection good enough to capture a clear image of a vehicle passing at speed? Also - very importantly - if it is doing motion capture to local SD card, and two vehicles pass with one being close behind the other, will it continue to do motion detection and take snapshots while it processes the first vehicle? In other words, if someone is tailgating another vehicle closely, would it detect both vehicles and take a picture?

Lastly, if we added an infrared flood light (something very bright) would that make night capture better? In other words, with additional flood lighting, could we increase the shutter speed for sharper night captures?

The camera will be installed roadside and elevated about 8 to 10 feet.

Thanks for your recommendation.

 

[bickford]

ANPR Camera go on dahua website
Google is your best friend

BICK

 

[bp2008]

How much light is there during the night? If there is very much at all, this would be a great choice as it will be able to capture colors at night better than most other cameras: IPC-HFW4239T-ASE TrueColor - new bullet camera.

Additional lighting does enable you to increase the shutter speed for sharper captures. More light and faster shutter speed also helps reduce the glare of headlights if they ever face the camera directly.

Modern video security systems are designed to record video clips, not just snapshots. In fact it is much easier for a computer to just record all motion than to try to figure out which one or two frames are most important and record only those. So two vehicles close to each other should both be recorded fine. They just might not be identified as separate events.

If you have a goal to read license places, that has its own unique set of challenges, especially at night where you must tune the camera such that license plates are exposed well, which makes the rest of the frame mostly black. In such cases it is often ideal to have two cameras: one zoomed in tightly for reading plates and another for identifying color/make/model and other identifying characteristics.

I can't say anything about Dahua's built-in motion detection as I've honestly never used it. I use Blue Iris instead.

Blue Iris does do a somewhat decent job of choosing a thumbnail image intelligently, at least, when pointed at a road and capturing occasional vehicles. I have two cams pointed at the same road here, and for the most part they both record a clip of every vehicle that passes.

 

[Marble68]

Thanks for the feedback! Reading the license plate via OCR would be nice - but human readable is adequate for purposes of this project.

I see a lot of the cameras have motion detection, and can grab a video segment or multiple snapshots - but the camera I have right now - when it detects motion and is saving the image to the SD card - it doesn't perform any motion detection or saving - so data could be lost.

It might be good enough, I suppose.

I'm actually trying to learn how to do the video grab on a computer with opencv at the moment - it may be the way to go anyway.

Thanks again!!!