<?php  convertToFlv( "some-video-input.avi", "output.jpg" );    function convertToFlv( $input, $output ) {     echo "Converting $input to $output<br />";     $command = "ffmpeg -v 0 -y -i $input -vframes 1 -ss 5 -vcodec mjpeg -f rawvideo -s 286x160 -aspect 16:9 $output ";     echo "$command<br />";     shell_exec( $command );     echo "Converted<br />";  }  ?>