Gstreamer and compatibility
A great strength of Pitivi lies in the fact that it uses the GStreamer multimedia framework. GStreamer is used by dozens of multimedia applications across desktop environments, operating systems and architectures.
For Pitivi users, this essentially means two things:
You can, in theory, import pretty much any media file supported by GStreamer (see the sections below for more details).
You can render your projects using any supported container and codec combination from GStreamer.
To maximize Pitivi's capabilities and reduce the possibilities of bugs, a very recent version of GStreamer is recommended. This is because Pitivi developers work hard on fixing problems directly in GStreamer instead of putting temporary workarounds inside Pitivi.
A word about editing-friendly codecs
Some formats, like MPEG, are oriented towards playback only, and do not compress each frame independently. While it is the goal of Pitivi to support working with these files, certain operations (like rapid seeking) will not perform as well as they would with frame-independent compressed video (such as MJPEG or DV).
The Good, the Bad and the Ugly
GStreamer plugins come into three categories: good, bad and ugly. You may need to install plugins from any category to ensure compatibility with your media files. Whether or not you install them is up to you, and may depend on your country's jurisdiction regarding software patents. An overview of gstreamer plugins and their classification into categories can be found on the Gstreamer website.
The "Good" plugins are high quality plugins under the LGPL license. These plugins are considered safe and recommended at any time. To install them, search for packages containing gstreamer plugins good in your distribution's repositories.
The "Bad" plugins are plugins whose code quality is not good enough, or are not considered tested well enough. The licensing may or may not be LGPL. To install them, search for packages containing gstreamer plugins bad in your distribution's repositories.
The "Ugly" plugins are good quality plugins whose license is not LGPL or with licensing issues. To install them, search for packages containing containing gstreamer plugins ugly in your distribution's repositories.
In addition to the Good, Bad and Ugly plugins, you may want to install the gstreamer-ffmpeg package to have access to ffmpeg's set of codecs.
Image file formats
While it is not feasible to list every possible combination of supported video or audio formats, it is however possible to list the static image formats that can be imported: JPEG, PNG, JPEG 2000, PNM and SVG.