Get video duration without ffmpeg function

If we need to get video duration in php if server not support ffmepg function than use following code to get duration.

    ob_start();

    passthru("ffmpeg -i ".$videoName." 2>&1");
    $duration = ob_get_contents();
   ob_end_clean();

    $search='/Duration: (.*?)[.]/';
    $duration=preg_match($search, $duration, $matches, PREG_OFFSET_CAPTURE);
    $duration = $matches[1][0];

    list($hours, $mins, $secs) = split('[:]', $duration);

    echo "Hours: ".$hours." Minutes: ".$mins." Seconds: ".$secs;
    $duration=$mins.':'.$secs;