|This is a video codec. The name to use at the command line is h264.|
H.264, or Advanced Video Coding (AVC) is a video codec described by MPEG-4 Part 10. It is able to be used in a wide spectrum of applications scenarios ranging from real time streaming use in video conferencing systems to file storage.
For a technical description read http://www.dspr.com/www/technology/csvt_overview.pdf