FFMPEG-PHP
From HwdMediaShare Documentation
ffmpeg-php is an extension for PHP that adds an easy to use, object-oriented API for accessing and retrieving information from video and audio files. ffmpeg-php can access many of the video formats supported by ffmpeg (mov, avi, mpg, wmv...).
ffmpeg-php is a very useful tool, but not very well supported by servers. For that reason, hwdVideoShare uses ffmpeg-php as a primary method to get the length of video files however, if the ffmpeg-php extension is not available then an alternative method is used to try and find the length of the video file.