The Shard is the tallest building in Western Europe, and has a great view of London. The condos in the building are very expensive, and a tourist ride to the top of the building costs £24.95.
Since the value of the view is so high, [Willem] wanted to quantify the quality of the view at any given time. His solution is the Shard Rain Cam. This device combines a Logitech webcam with a Raspberry Pi to capture a time-lapse set of images. These images are fed to a Python script using OpenCV which quantifies the cloudiness.
[Willem] also had to build a weatherproof enclosure with a transparent window for the camera and RPi. ‘Clingfilm’, which is British for saran wrap, and mineral oil is used to improve the waterproofing of an IP54 rated enclosure.
The resulting data is displayed on www.whatcaniseefromtheshard.com, which provides an indication of whether or not the view is worth £24.95. All of the Python code is available, and is a good starting point for learning about image processing with OpenCV.
Willem Do some work, or i’ll post pictures of you watching ascii pr0n
(p.s i sit opposite this guy)
Err.. I don’t get it. What do you do with the mineral oil?
You drown everything in mineral oil to prevents water getting in, and everything will run happily dunked in the stuff. But I am not sure if potting it, or something similar might have been a better solution.
I think he coated the cling film with it.
There’s also this product: Ultra-Ever Dry. A bit pricey, though.
Does that work as advertised? Seems too good.
No idea. I’m tempted to try it, though. May be one day. I want my house and my car covered with the stuff. (c:
It does, but it’s not very durable. In fact, it’s rather fragile. Additionally, since you must spray the product onto whatever you’re liquidproofing, some of it will get into the environment if you do not contain it, meaning it is unwise to use it on your house. Additionally, both the top and bottom coats are extremely flammable, greatly increasing your risk of fires. The bottom coat contains hexane, which has been referred to as a potential carcinogen, and has a known hazardous, systemic effect on human beings. However, it only contains hexane in low quantities. Regardless, if you release enough of it into the air (about 17 pounds), you will have to report it. The videos they’ve released to advertise their product show them spraying it into the open air. Please contain it.
References: http://www.spillcontainment.com/sites/default/files/Ever%20Dry%20MSDS%20-%20Top%20Coat%20-%2010-12-12.pdf MSDS sheet for the top coat
http://www.spillcontainment.com/sites/default/files/Ever%20Dry%20MSDS%20-%20Base%20Coat%20-%2010-12-12.pdf MSDS sheet for the bottom coat
http://web.archive.org/web/20070519002303/http://www.nsc.org/ehc/chemical/N-Hexane.htm Hexane info
Yes, its like in the video. Some solvents like alcohol can degrade the coating. Typically the degradation is reversed when its dry again.
That cam needs better optics
And why histogram? I would suspect clouds affecting sharpness more than color palette. You can analyze sharpness with FFT
http://stackoverflow.com/questions/7765810/is-there-a-way-to-detect-if-an-image-is-blurry
Btw cheap older compact camera will work TONS better than USB computer camera.
http://www.gphoto.org/doc/remote/
You will get real optics, and something like PowerShot A520 will cost you maybe $10-15
I think the camera is having issues because it’s covered in plastic wrap and bathing in mineral oil.
Cool project. Couldn’t you also just scrape visibility data from an aviation site? But if the goal was to come up with something independent of others’ work, then this is a neat solution.