Drone Fireworks!

Drone fireworks - still a work in progress, but this is me flying a drone in the dark. I'd seen some of the professional outdoor drone displays using GPS swarms and wanted to try something more low tech for Guy Fawkes night. The theory was good, the only thing I didn't account for was not being able to see the drone in the dark. This makes flying it really hard. And, yes, I left one of the many crashes in the edit for you to watch.

Filmed with a RunCam 2 camera, using a 100mm custom drone.

This is what I was trying to achieve:

Using StarStax image stacking software for astronomy

I did some experimentation using image additive blending using Image Magick, but it ends up saturating the background to blue. Then I tried some software that's designed for combining astronomy images, which handles the dark background and bright foreground much better. The picture above was made using StarStax with their "lighten" filter. Although, I'm not 100% sure how this filter+composite operation works, I now want to write my own software and have a play around with my own image filters.

Just to finish off, here's my first attempt using ImageMagick:

Image Magick "Composite -compose Plus" filter

I really only put this in because of the weird face that appears on the bottom left track. It was enough to make me wonder whether it's a reflection of my face on a reflective surface in the dark, but I think it's just where the drone crashed out of shot at the end. Spooky, though?

With both methods, I converted the 48s movie to a sequence of approximately 2200 jpeg frames using the following command in ffmpeg:

ffmpeg -i 20181104_203958.mov img%04d.jpg

This gives me a set of jpeg images in a directory called, "img0001.jpg", "img0002.jpg" etc.

Then the script to do the conversion with ImageMagick is as follows:

magick convert -size 1920x1080 canvas:black temp.png
for /r %%i in (img????.jpg) do magick composite temp.png "%%i" -compose Plus temp.png

This gave the the blue image, above.

As I say, this is still a work in progress.