KPEdit
KPEdit - A 2D skeletal animation editor.
KPEdit is a skeletal animation editor for game developers and animators. It may be a free alternative to the motion capture systems. The application provides functionality that allows the user to create realistic video-based animations. Prerecorded videos can be used as a reference in order to construct skeleton movement sequences. Other features such as interpolation, transformations and video rendering are also available as built-in functions as well as external modules.