Extracting Lightning Strikes From HD Video

Lightning photography is a fine art. It requires a lot of patience, and until recently required some fancy gear. [Saulius Lukse] has always been fascinated by lightning storms. When he was a kid he used to shoot lightning with his dad’s old Zenit camera — It was rather challenging. Now he’s figured out a way to do it using a GoPro.

He films at 1080@60, which we admit, isn’t the greatest resolution, but we’re sure the next GoPro will be filming 4K60 next. This means you can just set up your GoPro outside during the storm, and let it do it what it does best — film video. Normally, you’d then have to edit the footage and extract each lightning frame. That could be a lot of work.

[Saulius] wrote a Python script using OpenCV instead. Basically, the OpenCV script spots the lightning and saves motion data to a CSV file by detecting fast changes in the image.

graph of lightning

The result? All the lightning frames plucked out from the footage — and it only took an i7 processor about 8 minutes to analyze 15 minutes of HD footage. Not bad.

Now if you feel like this is still cheating, you could build a fancy automatic trigger for your DSLR instead…

The Raspberry Pi Action Camera

Action cameras like the GoPro, and the Sony Action Cam are invaluable tools for cyclists and anyone else venturing into the great outdoors. These cameras are not really modifiable or usable in any way except for what they were designed for. [Connor] wanted a cheaper, open-source action camera and decided to build one with the Raspberry Pi.

[Connor]’s Pi action cam is built around the Raspberry Pi Model A+ and the Pi camera. This isn’t a complete solution, so [Connor] added a bluetooth module, a 2000 mAh battery, and a LiPo charger.

To keep the Pi Action Cam out of the elements, [Connor] printed an enclosure. It took a few tries, but eventually he was able to mount everything inside a small plastic box with buttons to start and stop recording, a power switch, and a USB micro jack for charging the battery. The software is a script by [Alex Eames], and the few changes necessary to make this script work with the hardware are also documented.

This was the most intensive 3D printing project [Connor] has ever come up with, and judging by the number of prints that don’t work quite right, he put a lot of work into it. Right now, the Pi action cam works, but there’s still a lot of work to turn this little plastic box into a completed project.

Mapillary For The Raspberry Pi

If you live out in the boondocks, out of reach from the Google Maps car, you might have noticed there aren’t too many pictures of your area on the Internet. Mapillary is hoping to change that with crowdsourced photos of the entire planet, with mobile apps that snap a pic and upload it to the web. [sabas1080] is bringing this capability to the most popular ARM dev board out there, the Raspberry Pi.

The Raspberry Pi is not a phone, the usual way to upload pics to Mapillary. There’s no GPS, so geotagging is out of the question. The Pi doesn’t have a camera or a screen, and if you’re taking pictures of remote locations, a battery would be a good idea.

All these pieces are available for the Pi, though; [sabas1080] sourced a display from Adafruit, the camera is a standard Raspi affair, and the GPS is a GY-NEO6MV2 module from the one of the numerous Chinese retailers. Add a big power bank battery, and all the hardware is there.

The software is where this build gets tricky. Mapillary has a nice set of free tools written in Python, no less, but this is only part of the build. [sabas1080] needed to connect the camera, set up the display, and figure out how to make everything work with the Mapillary tools. In the end, [sabas] was able to get the entire setup working as a programmable, mobile photo booth.

A self powered camera, showing output video

Self Powered Camera Powers Itself

Cameras sense light to create images, and solar cells turn light into energy. Why not mash the two together and create a self-powered camera?

The Computer Vision Laboratory at Columbia built this unique camera, which harvests power from its photodiode sensors. These photodiodes also act as an array of pixels that can recover an image. The result is a black and white video camera that needs no external power supply.

The energy harvester circuit charges up a supercap that provides power to the system. The frame rate of the camera is limited by the energy that can be harvested: higher frame rates require more juice. For this reason, the team developed an algorithm that varies the frame rate based on available energy.

The MC13226V microcontroller that was used for this build features an internal 2.4 GHz radio. The group mentions wireless functionality as a possibility feature in the future, which would make for a completely untethered, battery free camera.

Automated Weatherproof Timelapse System With DSLR And Raspberry Pi

[madis] has been working on time lapse rigs for a while now, and has gotten to the point where he has very specific requirements to fill that can’t be done with just any hardware. Recently, he was asked to take time lapse footage of a construction site and, due to the specifics of this project, used a Raspberry Pi and a DSLR camera to take high quality time lapse photography of a construction site during very specific times.

One of his earlier rigs involved using a GoPro, but he found that while the weatherproofing built into the camera was nice, the picture quality wasn’t very good and the GoPro had a wide-angle lens that wouldn’t suit him for this project. Luckily he had a DSLR sitting around, so he was able to wire it up to a Raspberry Pi and put it all into a weatherproof case.

thumbOnce the Pi was outfitted with a 3G modem, [madis] can log in and change the camera settings from anywhere. It’s normally set up to take a picture once every fifteen minutes, but ONLY during working hours. Presumably this saves a bunch of video editing later whereas a normal timelapse camera would require cutting out a bunch of nights and weekends.

The project is very well constructed as well, and [madis] goes into great detail on his project site about how he was able to build everything and configure the software, and even goes as far as to linking to the sites that helped him figure out how to do everything. If you’ve ever wanted to build a time lapse rig, this is probably the guide to follow. It might even be a good start for building a year-long time lapse video. If you want to take it a step further and add motion to it, check out this time lapse motion rig too!

Camera Slider

Camera Slider Utilizes Skateboard Trucks

[Peter] wanted a camera slider and found some inspiration on the good ole ‘net. He then gathered some parts and came up with his own design. We’ve seen camera sliders made from roller blade wheels before but never one that uses skateboard trucks as the carriage! On each truck axle are 2 bearings spaced apart without the skate wheels. Each pair of bearings rides on one of two 48 inch long closet rods supported between two push-up stands. The top portion from an old camera tripod makes a handy mount that allows adjustment of the camera’s aim.

Some camera sliders are manual operated. This one, however, is lead screw driven with a goal of keeping the camera moving at a constant rate. A disassembled hand drill provides the motor, gearbox and speed control necessary to turn the lead screw. Although it works well at slow speeds, [Peter] admits that it becomes less usable as the speed increases. This is mainly due to the 5/16 inch threaded rod lead screw oscillating and whipping around after reaching a certain RPM. If you stick with a straight run, a belt-driven system might make those faster movements more smoothly.

Magic Lantern Brings Linux To Canon EOS Cameras

On April 1st the Magic Lantern team announced a proof of concept that lets you run Linux on a Canon EOS camera. Because of the date of the post we’ve poured over this one and are confident it’s no joke. The development has huge potential.

The hack was facilitated by a recent discovery that the LCD screen on the camera can be accessed from the bootloader. In case you don’t recognize the name, Magic Lantern is an Open Source project that adds features to these high-end cameras by utilizing the bootloader with binary files on the SD card. It’s long been a way of hacking more features in but has always been complicated by the fact that you must figure out how to play nicely with the existing firmware. Commanding the LCD was the last part of the hardware that had previously not been driven directly from Magic Lantern.

Now that the Linux kernel is in the picture, ground-up features can be built without dealing with the stock firmware in any way (and without overwriting it). We’re excited to see where this one goes. Currently it’s just a proof that you can boot Linux, it’s not actually functional yet. Here’s your chance to polish those kernel porting skills you’ve been holding in reserve.