Tuesday, 13 September 2016

Camera

I've been putting it off for a long time now, but I finally got another camera to use on the bike. Instead of helmet-mounting it, I went for a straightforward handlebar mount.

The camera itself is cheap, which obviously shows in the video quality, but at this stage I'm not complaining. It's called an Object - yes, I agree, that IS a stupid name - and it's a cheap copy of a GoPro that I bought at a petrol station for £20. I figured at that price it's worth taking a chance on a totally unknown make and model and to be honest I really didn't expect much of it.

The instructions are minimal, but suggests the camera can take 12 MP photographs! Not very likely at all! It turns out that the camera by default is heavily reliant on something called interpolation.

Now interpolation is a technique where software is used to calculate pixels that the CMOS sensor cannot actually see. Think of an A4 piece of paper, with a perfectly clean black line down the centre. To the left of that line the page it pure black, while to the right it is pure white, with the edge of the line being crisp and sharp.

If you used a camera relying on interpolation to take a photo of that sheet of paper, the line would no longer be clean and sharp, but fuzzy. This is because somewhere the software detected a white and a black pixel alongside each other, then inserted a few more pixels in between: a 25% grey, a 50% grey and a 75% grey pixel, in our example. These pixels never existed in the original image, but were artificially created. That is a simplified example of interpolation, and it becomes instantly obvious that it isn't something you wanted.

Indeed, early testing confirmed the video quality was VERY fuzzy, so I changed the resolution down to minimum, 640 x 480. That improved the image quality, but there's no escaping the fact that it's a cheap camera and when moving, the liquid effect is obvious on recorded video.

Still, it's way better than no camera at all, and aside from the less-than-stellar image quality, it does have rather good battery life. I used mine with an 8GB micro SD card, which (at 640 x 480 resolution) allows for roughly 2 hours of video. The camera will automatically switch off some time after having filled the SD card, and testing shows that those two hours of filming used up around a quarter of battery life.

That suggests (and I haven't yet tested it) that the camera would have a battery life of around eight hours, if used with a 32GB SD card.
Now I'll be very happy with 8 hours of battery as that means I can video the entire Dartmoor Classic.

The camera has a setting to allow for circular recording, where it will indefinitely over-write video previously recorded, but I'm not in favour of such drastic measures.I'm a geek at heart and anything that auto-deletes or auto-overwrites data makes me nervous!

Annoyingly, the camera breaks the video up into separate files of roughly ten minutes of video each, so if you wanted to use it with Suffervision or Dashware you'd need to first use a 3rd party utility to stitch all those segments together.

The audio quality is acceptable, except when moving, when the wind means you cannot hear anything other than wind noise. This is an important fact to bear in mind. On my old camera, I learned that you won't always be able to read the reg number, so when you have an incident on the road you always call out the reg number. That way you will have a record of it in the audio, even if not in the video, but with this camera (at least while on the handlebar mount) the audio will be useless, unless you were stopped at the time.

Anyway, here's an example of what the video quality is like - I had 2 separate incidents in this clip, at 3 minutes 30 seconds and at 4 minutes 20 seconds: