Okay, so I wanted to share something I’ve been messing around with lately. It’s about figuring out how many people are coming and going in a public spot, mainly for keeping tabs on things, you know, basic security awareness.
Getting Started – The Why and How
It started pretty simply. I noticed the entrance to a local community area felt a bit unsupervised, especially during off-hours. I thought, wouldn’t it be handy to just have a rough idea of the foot traffic? Not like spying, just getting a sense of busy times or unusual numbers.
First, I poked around online. Saw all sorts of high-tech gear, stuff used in big stores with fancy thermal sensors and complex AI. Way overkill and probably super expensive. Then I thought about those simple infrared beams, the ones that go ‘ding’ when you walk through. Cheaper, yeah, but seemed easy to fool or block, and running wires might be a pain depending on the spot.
Picking the Tools
I decided to try something different. I had an old webcam lying around, and figured, maybe I could use that? Connect it to a small computer, maybe a Raspberry Pi I had in a drawer. Seemed like a flexible approach, even if it meant more tinkering from my side. The main cost was just getting a weatherproof case for the camera and a long USB cable.
Setting It All Up
Finding the right spot was the first hurdle. I needed a place with a decent view of the main pathway, high enough so people wouldn’t just knock into it, but low enough to actually see people clearly. Plus, I needed power nearby. Ran an extension cord temporarily just for testing. Mounting the camera in its new case took some fiddling to get the angle right. Didn’t want it looking straight down, nor too far out.
Making it Count – The Tricky Part
This is where I spent most of my time. Just having the video feed doesn’t count people. I needed software.
- First Try: Looked for ready-made software. Found some, but many were either paid subscriptions or too complicated for my simple setup.
- DIY Attempt: So, I decided to try cobbling something together myself. I’m not a pro coder, mind you. Found some guides online using stuff like OpenCV, which is like a toolkit for computer vision. The basic idea was simple: detect motion, then try to see if that motion blob looks roughly like a person and if it crosses a virtual line I drew on the screen.
Oh, the headaches! Getting this right was tough. Shadows moving on a sunny day would trigger counts. Sometimes a group of people walking close together counted as one. A dog running past? Counted. Someone stopping right on the line? Double counted when they moved again.
Testing and Fixing (Lots of Fixing)
I spent days, maybe weeks on and off, just watching the feed and my little counter number, comparing it to reality.
- Moved the virtual line around.
- Tweaked the settings for motion sensitivity.
- Tried to make the code ignore things that were too small (like birds or blowing leaves).
- Adjusted the camera angle slightly.
It was a lot of trial and error. Very frustrating at times. I realised perfect accuracy was probably impossible with my simple setup, but I aimed for ‘good enough’ to spot major trends or anomalies.
How It’s Used Now
So, after all that, what I have now is a small computer screen that shows a number, updating every few seconds. It gives me a rough tally for the day. It’s not foolproof, but it does the job I wanted. If I see the number jump unusually high late at night, or if the total count for a day seems way off the charts, it’s a signal to just be more aware, maybe check things out if needed. It’s more about pattern recognition than catching individuals.
Final Thoughts
Looking back, it was an interesting project. Definitely learned a lot, mostly about how tricky computer vision can be, even for something that sounds simple like counting. It took way more effort than just buying an off-the-shelf counter, but it was cheaper and I got my hands dirty.
Was it worth it? For the learning experience, yeah. For a super reliable security system, probably not. If I needed something critical, I’d likely invest in a proper commercial solution now. But for a hobby project to get a basic sense of activity in a public space, this DIY route was a journey, that’s for sure.