Xtheater is a media playing tool for Unix. It has a flexible plugin architecture to allow for different UI and playback plugins. It has a plugin for a GTK UI, an smpeg-based plugin for playing mpg and mp3 files, and an AVI plugin for AVI and ASF files. It features seek, fullscreen, doublesize, GL rendering, and more.
The MPEG4IP package provides a set of tools to encode, stream, and playback audio and video. It uses the MPEG-4 standards for audio and video, and the IETF standards for streaming. The included player can either playback from local MP4 file or stream from a remote server via RTP/RTSP.