Keyframe Editing
From PiTiViWiKi
Contents |
Description
A demonstration of how keyframe editing might work in PiTivi. The effect parameters are controlled via keyframes. The purpose of this demo is to work out the behavior of interpolation curve widgets in PiTiVi. I might create a number of variations over time, so that I can experiment with the interaction.
To Use
- check out the project
-
$python keyframe.py
- double-click the curve to add a new point
- click-and-drag points to move them
- double-click points to delete
Note: There is currently a bug in which the start and end control points are initially drawn in the wrong location. Click and drag them a couple of times, and the curve will redraw correctly.
Screenshots
Who doesn't like screenshots?
 Curve editor in linear mode |
 Curve editor in cubic mode |
 Curve editor showing no interpolation |
Where to Get
Git repository here:
git://github.com/emdash/keyframe-demo.git
Progress
You can now add and remove points, and choose between global interpolation modes. Still working on the gst-controller back end. One issue is that the goocanvas Path element uses cubic bezier curves, which require two control points to draw, while the gst-controller back end uses a "natural cubic spline", which interpolates through the given points. Because of this, I don't think the curve is quite accurately drawn, but I need to speak to a math person in order to understand what to do differently.
