Calculate Audio file duration
getID3 can be used to calculate the size of the file.

$fileinfo = getID3_analyze(drupal_realpath($name2));
$playtime_sec = round($fileinfo['playtime_seconds'] / 60);

//Generate playtime in minutes (for display only), @type String
$playtime_mins = $fileinfo['playtime_string'];


use the following modules to integrate with views.
https://www.drupal.org/project/computed_field
https://www.drupal.org/project/getid3