convert music video to mp3 inside directory with ffmpeg

convertor.php

<?php
	$files = scandir(__DIR__);
	foreach($files as $file){
		$name = explode(".",$file);
		unset($name[count($name)-1]);
		$name = implode("-",$name);
		$name = str_replace(" ","-",$name);
		$name = strtolower($name);
		$name = preg_replace("/[\-]{1,}/i","-",$name);
		echo "Start Convert for " . $name . "\n";
		exec("ffmpeg -i \"".$file."\" -vn -acodec libmp3lame -ac 2 -qscale:a 4 -ar 48000 ".$name.".mp3");
	}