[Cin] Cinellera360: the ultimate free VR editor

[Stefan de Konink]

You got my clickbait? I got your attention.

Nothing on the internet mentions that Cinelerra is capable of editing 360 
video's, but it certainly is: with the help of ffmpeg's F_v360 plugin. 
Either creating the 360 content, or extracting it in a regular video.

So as you all already expected from my I was doing stuff with Cinelerra-gg 
that likely nobody did before and noticed some particularities that I 
really did not understand. My steps:

1. My project settings remain 1920x1080.

2. Just grab any equirectangular video bigger than your project size. The 
one I got my hands on was 4096x2048.

In my project I want to use a part of this video as illustration of the 
user experience. This would mean I need to project the equirectangular 
projection into a flat projection.

3. For the plugin settings that would be input=0 and output=4.

What I noticed when I modulated the yaw was that I would never see the 
entire view, then when rotating the back of the video would 'clip' at -180 
degrees.

4. When changing the camera to Z = 0.469 (1920/4096) I was able to get a 
360 degree rotatable camera.

5. Setting up d_fov = 120, the image would be closely mimicking the 
experience.


Now what Cinelerra bring you from this point. Keyframing a property of the 
plugin, and there it becomes interesting.
Plugin keyframes seem to give the control what we are looking for here. I 
can set the yaw using "Generate keyframes while tweeking", but what I would 
be actually looking for is the same set of curves that would be available 
when changing x,y,z,opacity etc. How would I get interpolation working?

Could anyone elaborate how Cinelerra knows it can interpolate some of the 
parameters, but not others?

And personally I think what is more fundamentally lacking in Cinelerra: a 
timeline view analogue to Blender where any property can be placed in view: 
where I would suggest to normalise the min and max to sensible properties 
opposed to the current: stack everything on the track and break your 
project by an unintended mouse click.

-- 
Stefan