Spring 2020: First Corona lockdown was when we first thought about what to do with our old smartphones, and the idea of using them as a webcam came to our mind. The task seemed simple, and it would only took a few evenings to accomplish – but many iterations later we still consider it work in progress. We had converted an old Android smartphone – unused for quite a while, broken display, not really kaputt, but of no use anymore – into a webcam, and we ended with an automated timelapse creator in a few bash scripts. In German, we refer to our little project as “Der Zeitraffer von Regensburg” – you try to translate that. 🙂 And yes, the project’s name is spelled with a “k”.
The Regensburg Corona Lockdown Zeitfresser
Update 2021: Here’s a 650 MByte large video that runs from November 17, 2020 to May 20, 2021, ~44.000 individual pictures. Alongside many glitches and fuzzynesses and reflections (yes we decided to keep them, and also the different length-of-day which is a function of fog and light), it shows the whole Regensburg COVID-19 lockdown as seen from our offices. It will start right away, if you click. Feel free to download, use and spread it. Just let us know and stick with the terms of the CC-BY-SA and name us. And we’re happy to receive mail. 🙂
Do you notice the one solitary tourist boat arriving at around Christmas? They are back now, like the tourists are. And there’s none of the ugly speed boats or the nasty jetski posers jumping, roaring and more. It was quiet, then.
An old Android phone …
May 2020: Some Android apps, a scheduled daily reboot (of the phone, of course), a webserver on the phone and some raspberry Pi and ImageMagick magic later we now have this working webcam that takes thousands of pictures every month – every five minutes during the day, every two minutes at night due to limitations of quality of the camera and the app’s autofocus settings.
Later in 2020: the raspi has retired from the job, and thus the webkam task moved to our little fileserver – which is also storage for the images. We will continue to document here what and how we’ve done it. Until then, here’s the July timelapse in low-res (Still ~ 130 MB, I guess).
Update November 2020: We now automatically create monthly timelapses, and the fuzzyness detector in Image Magick sorts out blurred images. Well, to be honest, it sorts out some. Or it tries. 🙂 Next project challenge: Use machine learning for sorting out blurry images. (Feed with photos that are on focus). Might be tricky, because 24 hours a day, weather and clouds plus people cars boats and other stuff moving. We will see.
Update June 2021: We had to swap the phone, since the battery pack got a little bloated. To prevent that in the future, Adb over Wifi delivers some temperature and battery state to our monitor. Image format has changed, so the new pictures will be 16:9, and we cannot combine them with the old timelapses. Unless, yes unless we let Image Magick crop one or the other input. We will see.
Disclaimer: This has been and is an ongoing project, so beware – changes will occur. 🙂
Todo: Specify the apps and tools we’re using, giving the open source developers the kudos they should get. Corona Video: Add fade in/out, correct preview image.