Video Light Painting - The Easy Way
One of the most repeated questions we get on our light painting tuts is: "Yes, but how about video? Can you light paint in video?"
Well, the short answer is yes you can, you would need to take roughly 24 pictures per second, drawing and re-drawing your light for every single frame. EVERY.SINGLE.FRAME. There are two great examples for that method embedded at the end of this post.
There is an easier way, though less purist made by kdenlive developer Simon Eugster. You would need some Linux skills (and I know many of you are Linux Ninjas) and the usual light painting tools of the trade. Sample and more info after the jump.
Ok, this is not SOOC (Strait Out Of Camera) purist light painting, instead it uses three pieces of software: Kdevline, Frei0r and a Light painting plugin. (actually, the Light Graffiti effect is now in the frei0r repository and will therefore be in the next release of frei0r)
Frei0r (yup, that is a zero) is cross-platform framework for video effects. Actually, if you know a bit of coding, the frei0r is actually a single H file.
Simon Eugster's Light Painting Plug In
This is where the smarts is for this specific application. Written in C++ the plugin provides some easy ways to control light painting done in videos. There is a full description of the design, motivation and code on the Kdenlive blog.
How It Works
The idea is kinda simple, the plug in takes a snapshot of the lightless background and then it follows the bright lights in the video to compute what is "light painting" and what is "ambient light". It then makes sure that the light painting stays on for the duration of the video.
The smarts lies in the ways the plugin sees the light. The longer the light hits the sensor light a certain location, the brighter this location will be.
Now, it is your turn. Follow the instructions here - you will need a Linux box and some compiling know-how. You can use the comments here to ask questions. (If you are wiling to wait a bit, the next version of kdenlive will have this built in.
Other Video Light Painting
As promised two other light painting videos done the "hard way".