Battery Powered External Camera

[Dave Rice]

I have a customer who would like to see who’s at the door before answering it. A Ring doorbell is out as the front door is very close to the pavement and people I know complain about theirs being set off all the time and they have a 20′ driveway.

There is no handy mains anywhere near but there’s a handy drainpipe to hide a cable behind for my traditional route to the loft for a PoE switch for a camera. The labour and extra equipment expense doesn’t make much sense for a single camera though.

So I had a look about for battery powered systems and was pretty settled on a Netgear Arlo. Had they been ready to go a month ago that’s what would have gone in. However there’s a lot I don’t like about the Arlo; a proprietary WiFi unit, only 7 days cloud storage and cost. However the alternatives all seemed a bit cheap and nasty with lots of gotchas.

Got the call on Friday, could go this Thursday? Had another look on Amazon and found a system I’d not seen before, Reolink. There was a flash sale of £90 for a Reolink Argus Pro with Solar Panel Power and Rechargeable Battery.  It uses the house WiFi and records to an SD card. The solar power would get around any high battery usage as some Arlo users report. The (proprietary) battery is easy to recharge but obviously needs to be taken off the camera which can be a PITA.

So it’s currently on test strapped around my drainpipe using the included tree mount. Setting it up is very easy and all done through a phone app with voice prompts. It’s little more than attaching it to your WiFi and giving it a name. The app creates a QR code which you put in front of the camera, set up done. Then you can go into the app and set up push notifications and email if you want. Resolutions are set at HD 1080P 15fps or Fluent 640 x 360 5fps which is sensible but you can change the fps. The view is 130 degrees and the PIR sensor can be set to high, medium or low. IR can be turned on or off but is best left on auto.

As you can see the HD picture is fine and the fluent is more than acceptable on a phone. Whilst there is a 4~5 second lag the push notifications work OK for seeing who’s ringing the doorbell. The 2 way audio is a bit of a waste of time but does work. Sharing amongst family is as simple as scanning a QR code your app creates. There is a Windows and Mac app.

Playback of clips is dead easy and can be downloaded to whatever device you’re on. I put a 64GB SD card in as it’s what I had laying around, I think you could easily live with a quarter of that or less. Photo clips are shareable inside the app in much the same way Google Photos does. Email notifications can include a photo clip.

Weak points:

• The mount, the column just clips onto the metal mounting plate, easily nicked. So I’ve ordered an alternative at a fiver each. The solar panel mount is already a secure one.
• It needs a strong WiFi signal and being the other side of a brick wall doesn’t help. Using my WiFi which is fine anywhere in the house was too flakey coming down 3 floors and a shallow angle through the outside wall. I set up a spare TP-Link TL-WA801ND AP in the garage and that sorted that.
• You must remember that this is not a surveillance camera. Whilst you can invoke a time limited live stream at will it’s designed to sleep until motion is detected or the battery would last no time at all. But that’s all most people want.

I think this one will be a keeper, but we’ll see how it works tonight.

[Ed P]

The law seems a bit flaky on ‘surveillance’ cameras. Today I had a policeman call to ask if one of my cameras could monitor passing traffic. I said yes it could, but doesn’t (except by accident) as I have set it up to only record when there is movement in my own drive. I said that I thought there were privacy concerns about deliberately recording events not directly connected with  my property or possessions, and asked if that were correct. He said yes, but it seems a grey area. I asked if he wanted me to record everything, but he declined saying he would come back if they did.

He would not say why the police wanted to know. (I suspect it was a survey the police are doing to see the extent of ad-hoc recording in the area, as I’m not aware of any criminal activity in the vicinity.)

[Ed P]

I guess this should be in the Pi section but Dave may have a professional interest.

The price of true FLIR kit is starting to plummet. Pimoroni (an IOT accessories company) has just released a thermal camera add-on for the Pi. Although the 32×24 pixel resolution is useless for surveillance work, I would guess that the resolution would be sufficient to detect a moving person at 15 metres.

I’m getting one to play with as I see it having uses for monitoring thermal insulation and other things. The relatively low cost, programmability and  1 degree C thermal resolution over a large working range, also makes it of potential use in a diverse numbers of things e.g. monitoring farmers hay storage to detect ‘hot’ spots, or peering at mobos for bad traces etc. One of those items only limited by imagination and ability.

I’ll probably pair it up with a cheap pi-zero camera to make the heat maps a bit more intelligible.

[PlaneMan]

I’m waiting for FLIR on a mobile, built in, not some clunky, crappy 3rd party add on.

The FLIR module for Android (and iOs) is £216. Battery life of an hour is the downside. When they get to £100 odd I might bite.

[Dave Rice]

Thermal is an area I’m very interested in.

Ed, all that’s needed is to open or close a circuit attached to the alarm input of a camera or NVR to set a camera recording. For excessive heat or fire detection the low resolution may not matter. Or where there absolutely shouldn’t be anyone at night. Also the sensor could be a long way from the camera if range is an issue.

I have one of these cameras (it was destined for the now in administration care home) that has an alarm input. Let me know how your tinkering goes, I also have a Pi sat doing nothing.

[Ed P]

PM I agree the Pi FLIR is klunky, but it is 20% of the price of an Android add-on. The Pi is also relatively easy to integrate into any system along the lines Dave outlines. i.e. use Pi FLIR as a sensor rather than a proper camera.

I’ve played with a son’s iPhone FLIR add-on. The pics are almost at iPhone resolution, BUT they have the usual OEM problem of being a closed box for developers (plus the usual Apple problems!). The other major issue is that the ‘detected’ temperature is  dependent on the emissivity of the object as well as apparent temperature. i.e. My son’s kit is just as good at detecting moss on a roof as it is warmer hot-spots.  To an extent each application has to be tailored with such and other factors in mind.

To feed back a little on the ‘range’ issue that Dave raised, afaik range is not the issue but resolution is. With only 768 measuring points on an image, the detectable object size will be directly proportional to the focal length of the lens. The Pimoroni ad shows both standard and wide angle lens options so I guess if one needed a longer range a telephoto could be used. (I plead ignorance here as I have no idea of the problems faced with using different focal length/glass thicknesses and FLIR chips)

[Dave Rice]

Commercial thermal cameras don’t have a fine resolution, that’s not the point of them. You’d pair them with an optical camera (maybe a PTZ with very long range IR) if you need detail. The cheapest HIKVision Thermal Network Bullet Camera, 10mm lens, 384 × 288 is £1,400 plus VAT but has 14 colour layers and behaviour analysis: Line crossing, Intrusion, Audio exception, Region Entrance & Exit.

For fire detection up to 100 metres the CIQURIX FCamSol0 1080p @ 25fps, 4mm lens, up to 55m flame detection, smoke detection, Detection time <15seconds is the same sort of price and is internal only. That’s the sort of duty I was thinking about for the Pi.

By long range I meant the detector may need to be much nearer the potential heat source (due to its poor resolution) with the optical to provide either / or high mpx and wider scene. As you say, with some thought the potential problem solving is very wide indeed.

[Dave Rice]

Back to the original thread ?

Night time shot.

[Author]

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