MPlayer

MPlayer is a powerful command-line media player.

Please note MPlayer is no longer maintained and its fork MPV supports all mplayer functionality and more.

Emerge
Install :

GUI tools
There are a number of different GUI's for MPlayer with different levels of functionality. Some notable ones include:



Streaming videos from websites
MPlayer has the ability to stream videos from websites. As a prerequisite, must have the   and   USE flags enabled. To do this, simply enter the command:

Where url is the URL of the video.

Disable screensaver while playing a video
Using qdbus (Qt/KDE):

For systems using xscreensaver alone:

See this FAQ entry for more informations.

My video won't play!
MPlayer uses USE flags to enable and disable support for various codecs. If a particular type of file will not play in MPlayer, first check which USE flags MPlayer was emerged with. Update the USE flags to support for the format you are trying to play and recompile.