Infrared Raspberry Pi

When I ordered my Pi Zero W with a no-IR-filter camera, I also ordered a single infrared LED. This was enough to prove that I could illuminate things with IR, but not really good enough for more than a small dot of light.

So, then I ordered 50 x £0.04 infrared LEDs from RS (which arrived overnight!) and wired them up yesterday onto a single breadboard powered by a regular USB 5v power supply. You can see the layout in the first picture.

Here's a scene: the first with natural light showing the LEDs on a board, and the next two with infrared illumination. The two infrared scenes appeared almost pitch black to a human eye.

And then I set it up overnight, with a timelapse video of myself sleeping:

Raspberry Pi Zero W + cam timelapse

I got a Raspberry Pi Zero W and a camera module.

I wanted a timelapse video.

This is how I did it:

Capture a sequence of image frames

This will capture a sequence of images (forever) approximately every minute, with the filename being a unix timestamp.

while true; do raspi-still -o $(date +%s).jpeg ; sleep 60s; done

Leave this to run for as long as you want to collect frames, and you'll end up with a bunch of numerically named files, like this:

$ ls
1504014800.jpeg
1504014866.jpeg
1504014931.jpeg
...

Combine the sequence of image frames into a jpeg

After you've got all the frames you want, use ffmpeg to join the frames together. I do this on a different Linux box (my laptop) but you should be able to do it on the Pi too.

First make a command file listing all the jpeg files:

ls *jpeg | while read a ; do echo file $a; done > e.cmd

Next, feed that command file into ffmpeg to generate a video:

ffmpeg -f concat -i e.cmd -b:v 1500000 -r 24 -c:v libx264 e8.mp4

As a result, the output video should be in e8.mpg which is in a form suitable for playing with vlc or uploading to YouTube.

bunny webcam

I got this webcam for looking at pet rabbits for my girlfriend's birthday. (webcams, dear children, are something still fascinating for people born before, say, 1985)

The set up was pretty straightforward. I plugged it into the local ethernet and it appeared at 192.168.1.239. The local ethernet uses 192.168.1.0/24 but I think maybe have been just chance that it configured itself that way - it wasn't using DHCP out of the box. When I switched on DHCP it reconfigured itself to a DHCP-allocated address in the same range.

The supplied manual (on paper) describes downloading and installing some setup.exe to configure, but I ignored that, and using nmap discovered it was running an http server on port 81. Logging into this as admin, with no password, I found myself able to view and control the camera without need for any software.

I couldn't get the wifi working, but only spent 10 mins or so on that - we decided it would be best placed right by a wired ethernet port, so there was no need for that.

We attached it to the underside of an Ikea table using electrical tape. There was a balance to strike between being low enough to get a good angle, but high enough that they can't eat the camera or the wires. I would have loved to have put it in the cage with them, but the lifetime of the wires would have been measured in minutes, or possibly seconds.

The camera has motors to pan and tilt, though where its installed that isn't really necessary, and the whirring of the servos seems to scare the white rabbit a bit. That one likes to sit looking at the camera on the other side of the fence, hanging off the underside of the table.

There's a night vision mode too. The camera is surrounded by a ring of infrared LEDs - actually also a bit visible red too. These are turned on by a CdS cell above the camera lens (so you can trigger them with your finger rather than needing to put the camera in the dark).

The user interface is clunky but functional. The main page looks like this, with arrows at the top left to drive the servos. There are admin menus too, which appear even if you aren't authorised - they just don't work for non-authorised users. This clunky interface means its not a good camera for streaming to the public at large.

So, for £40, was this worth it? yes

(btw, not all the pictures in this post were made with the webcam - for example, the pictures of the webcam were taken with an iPhone rather than a complicated mirroring optical arrangement)