[Tade0]

This takes me back to the time when I wanted to determine which of my two cats is the one who makes the first move in their daily game of shess (it's like chess, but both the colours are black/brown and you don't move pieces - you just place them) in the bathroom.

I hooked a webcam to an old netbook and downloaded an app which would take a picture whenever it detected motion.

What I didn't take into account was the mirror in the hallway which during sunset would reflect sunlight at just the right angle to hit the toilet bowl.

In the end my results were a time-lapse of the sun shining on porcelain, because the mirror was far away enough to make the sun's movement trigger the motion detection sensing done by the app.

[jambo135]

haha I have experienced lots of these problems while testing and tried my best to build in logic to detect 'real' motion. However since I wanted it sensitive enough to detect things like a slow moving woodlouse there will always be false detections unfortunately. One of my tests I couldn't work out why tin foil was flagging as motion, turned out it was the moon outside the window hitting it at different angles during the night!

[johnchristopher]

That's why you want IR motion detection ^^.

Picture based detection can be a time sink by itself.

[mescalito]

Have you found out which cat was it in the end?

[Tade0]

Nope, but I discovered that the older one liked to drink water from the bathtub, so there's that.

He's in kitty heaven now, but the younger one proved to still be an avid shess player when my SO had to take him along with her while she was working seasonally as a hotel receptionist. He found a worthy opponent there, so it might have been him from the start.