Synfig

Synfig (a.k.a. Synfig Studio) is an open source 2D graphics and animation editor. Its native file format is .sif, which is based on XML. It also has an .sifz format (gzipped .sif), and an .sfg format (a ZIP-based package that also includes the assets used by the .sif file).

Specifications

 * Synfig Studio Documentation Wiki: Sif Format

Software

 * Synfig · Source code at GitHub
 * InkScape - Can write .sif

Sample files

 * https://github.com/synfig/synfig/tree/master/synfig-studio/images - *.sif

Links

 * Synfig
 * Synfig website
 * Synfig Studio Documentation Wiki: File Formats
 * Synfig Studio Documentation Wiki: History