Jump to content
algilson

How would you improve this IR recording?

Recommended Posts

I have two systems -- one at work, and one at home. My home camera picked up some activity a few nights ago, and I wondered if there's anything that you would have done to make this recording better:

 

 

The system used is a Dahua HWF3200S feeding an iCode iCatcher server. The frame rate at the time (I believe) was 4 FPS, which I have since increased to 10. What else could be done to make this better?

 

Thanks,

 

- Al

Share this post


Link to post
Share on other sites

If you can get the subject to stop closer to the camera or used a longer lens. Rule of thumb is the face should be at least 80 pixels tall to be identifiable and when you add noise at night, it should even be larger. The subjects face in your video is about 35-37 pixels tall which is worthless anytime of day. So you have two choices, get a narrower lens, maybe a 6mm lens, or increase your resolution to 5MP or a combination of both. For my driveway, I use 3MP camera because it gives me 50% more vertical pixels and I use a narrower lens, 4.2mm vs 3.6mm you are using.

Share this post


Link to post
Share on other sites
If you can get the subject to stop closer to the camera or used a longer lens. Rule of thumb is the face should be at least 80 pixels tall to be identifiable and when you add noise at night, it should even be larger. The subjects face in your video is about 35-37 pixels tall which is worthless anytime of day. So you have two choices, get a narrower lens, maybe a 6mm lens, or increase your resolution to 5MP or a combination of both. For my driveway, I use 3MP camera because it gives me 50% more vertical pixels and I use a narrower lens, 4.2mm vs 3.6mm you are using.

You stressing point about vertical PPF

I would say Horizontal kinda more important

Share this post


Link to post
Share on other sites

Tougher to measure horizontal unless the subject is facing directly forward. In this case, the best image was probably a profile shot and you can't apply the same rules.

Share this post


Link to post
Share on other sites

Before you can deside your problem I would first sort your existing camera out

 

Nothing to do with lens

 

First look at your IR feed back it covers over 50% of your image.

 

First is lens to dome cover ..... Seat that better then remove tree branch form camera view ...... Then see how your night time image is before anything else

Share this post


Link to post
Share on other sites

I agree about the IR. Another part of the puzzle with that camera is that you don't have it aimed to catch anything particularly well. Point it more left and really cover the driveway. You'll lose the front walk but you'll gain a more usable shot of cars in the driveway. Also, if it's possible to park the car in a better position to help the camera ID, do so. And regardless, you should take the footage to the authorities. They may know that guy very well and what you did capture may be enough for them. Your footage has some good frames.

Share this post


Link to post
Share on other sites

Wasn't paying attention to that but for a bullet, it has a lot of IR bleed, certainly worth fixing. I don't see the limit IR coverage and may appear that way because the black asphalt driveway and darker car absorb light more than the pathway.

 

But like I said, no matter what you do, you cannot identify a face that's 35 pixels tall even in full daylight. You need to get the subject to come closer to that camera, maybe put a sign that says "stand here". It's the biggest problem I see with DIY security, they go for the wide shot because they get great coverage but then fail to get the pixel density to be useful. I would get a 6mm 3MP camera just for the driveway and one just for the walkway.

Share this post


Link to post
Share on other sites

You need two cameras and more light. It doesn't cover much of your house, although it does a mediocre job of covering the driveway as well as being a "what's going on" cam. Probably does a good job IDing folks that come to the front door. I'd have probably a 6mm (maybe as high as 9mm) camera in front of your vehicle pointing straight out the driveway plus motion activated lights or some kind of dusk-to-dawn at the head of the driveway to help the driveway cam. 6 to 9mm is too narrow a FOV for an overview camera, but it'd give a much closer picture to ID any person or vehicle entering your driveway. Combine that with your current wide angle cam and you've got MUCH better information to work with. If you're stuck with one cam then I'd put more light in the driveway somehow. Standalone IR illuminator or plain old white light, preferably LED.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×