Labora: Mirrors, camera’s and security

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UNDER CONSTRUCTION

This article is under development. It is about an alternative approach to mirrors and cameras for security and observation for a mobile environment – in this case, the office on wheels “Labora”. Of course we want more and more but it starts with a basic solution and from that point we build on. This will be an article about hardware such as cameras, monitors and computers on the one hand, and software such as ZoneMinder and Linux on the other. Some important notes:

  • This article is for learning with plenty of starting points for moving forward.
  • The technology discussed on this page is of course also applicable to ships, construction project security, residential buildings and so on.
  • The emphasis is on low power consumption on the one hand and a cost-effective solution on the other.
  • $ means as user and # means as root.

Starting points

  • Financial:
    • Not unlimited and keeping it reasonable, yes, this is subjective.
  • Software:
    • Debian Linux
    • ZoneMinder
    • Internet access: tethering over an android phone
  • Power consumption
    • If there is no shore power then there is always enough left in the batteries.
    • A DeskMini with AMD 4650G consumes idling ~10 Watts plus very little overhead of an economical network switch (Edimax ES-5800G V3). Data traffic over IP causes hardly any increase.
      • Coding/decoding streams will be a CPU burden. Just storing streams does not.
    • Camera’s
      • The sum of the consumption of the cameras is difficult to estimate, per camera it is not much but multiplied by the number of camera’s it becomes considerable.
  • For publication, support is crucial. I decided to do a post on the forum.

Hardware

Let’s start with a layout:

  • Power supply: A 4S LiFePO4 battery (LFP) is used for power.
  • Computer: An Asrock Deskmini runs on 19V, step up, booster converter of at least 140W.
  • Switch and monitor accept USB power. Monitor requires DP power and thus a specific USB converter with sufficient power. Power for switch can also be drawn from computer.
  • Cameras with injected POE, 12V, see Voltage tolerances manufacturer (such as +/-25%) and, if possible, connected directly to LFP.

Camera test1: IVG-N8S

Specs

On Aliexpress a camera from or enster.com or jinjia-ccd.com (can’t figure out who is the manufacturer), type IVG-N8S, was bought. Excellent specs and a very attractive price. This camera is not on the ZoneMinder Hardware Compatibility List. A web-interface for 192.168.1.10 with user ‘admin’, without password (blank), does not work, it requires Windows executables. Bummer!

Some specs of this camera: Sensor Sony IMX415. Hardware based encoder on PCB: Novatek, NT98566.

Smallest footprint is possible by utilizing this PCB in a custom made housing. Apparently power supply is 12V +/- 25%, so these camera’s can be hooked directly on LiFePO4 (if 4S). Specified consumption: < 3W, measured: 2.3W.

Test 1: Linux RTSP

Is RTSP (Real-Time Streaming Protocol) supported?

On a Debian laptop I connected the camera to the RJ45 network port and did the following:

$ ip a
# ip addr add 192.168.1.5/24 dev <NIC>
$ nmap 192.168.1.10
$ ffmpeg -i rtsp://admin:@192.168.1.10:554/ -vcodec copy test.mp4

To clarify: first get a list of NICs, network interface cards, with ‘ip a’, next assign 192.168.1.5 to the wired NIC, use ‘nmap’ to retrieve ports, which turns out to be 554 for rtsp over TCP. Finally store the stream “as is” as a file using ‘ffmpeg’ – without encoding and decoding.

After cancelling ffmpeg with Ctrl-c and viewing the file, it turned out to be working. In fact, the quality is excellent and power usage is very low.

Test 2: Configuration

So far the good news. However, the date in the corner is wrong (least problem) and there is no known way to do some basic camera setup. I’ve decided to contact the manufacturer since the supplier simply says “no Linux support”. It is in their interest to try to support, solve some basic challenges. More on this after a response (if…). So for now here is a log of what I did. NIC1 in the layout above is IP: 10.105.24.0/24.

Computer

Power supply: LFP12V>StepUp19V.

Lots of complications like dark performance and monitor switching are to be expected.
Lots of question marks…

Monitor: micro HDMI or USB on dashboard, or ceiling, flippable. Something like ASUS ZenScreen OLED MQ16AHE or ASUS ZenScreen OLED MQ13AH.

Background

Fiat Ducato “as is”

From the FIAT factory (2021), a mediocre rearview camera and console monitor is available for the Ducato – it does its job, nothing more. The side mirrors, however, are excellent.

Dash-cam approach

A permanent (electronic) rear-view mirror was missing and as a solution, an electronic mirror – with an additional rear-view camera was installed. This proved so unreliable that another solution was desirable. What was wrong with the current solution – an electronic mirror recording both front and back?

  • Electronic interior mirrors have too little screen brightness in strong sunlight.
  • The built-in front camera delivers reasonable videos.
  • Despite being high resolution, the rear camera is a PITA.
    • Something like: doesn’t work, reboot, doesn’t work, reboot, works. I was done with it.
      • What turns out? Modern car lead-acid batteries are never full in order to be able to absorb energy from braking. Voltage is lower as result and long, too thin, power lines cause an extra Voltage drop, creating problems.
    • During night time the light sensitivity is not enough to make it a valuable addition.

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