- var_dump: documentation ( source)
- sscanf: documentation ( source)
<?php
$time = '00:02:14.31';
sscanf($time, '%d:%d:%d.%d', $hours, $minutes, $seconds, $centiseconds);
$total = $centiseconds
+ $seconds * 100
+ $minutes * 60 * 100
+ $hours * 60 * 60 * 100;
var_dump($total);