Supprimer automatiquement un caractere PHP

Bonjour,
lorsque je lis un tag d'une musique, avec un script PHP, il y a des losanges noir avec un point d'interrogation blanc dedans derrière le titre et le nom de l'album ...

Comment puis faire pour les retirer car ensuite, j'effectue un enregistrement MySQL pour un moteur de recherche, et s'il y a ces caractères ... dans les mots clés, ça ne va pas le faire ...

Merci de votre aide ;)

Voila la script pour ceux qui en ont besoin ... :

     <?
     function ReadTag($path)
     {
    
     $genre_array = array("Blues","Classic Rock","Country","Dance","Disco","Funk","Grunge",
     "Hip-Hop","Jazz","Metal","New Age","Oldies","Other","Pop","R&B",
     "Rap","Reggae","Rock","Techno","Industrial","Alternative","Ska",
     "Death Metal","Pranks","Soundtrack","Euro-Techno","Ambient",
     "Trip-Hop","Vocal","Jazz+Funk","Fusion","Trance","Classical",
     "Instrumental","Acid","House","Game","Sound Clip","Gospel",
     "Noise","AlternRock","Bass","Soul","Punk","Space","Meditative",
     "Instrumental Pop","Instrumental Rock","Ethnic","Gothic",
     "Darkwave","Techno-Industrial","Electronic","Pop-Folk",
     "Eurodance","Dream","Southern Rock","Comedy","Cult","Gangsta",
     "Top 40","Christian Rap","Pop/Funk","Jungle","Native American",
     "Cabaret","New Wave","Psychadelic","Rave","Showtunes","Trailer",
     "Lo-Fi","Tribal","Acid Punk","Acid Jazz","Polka","Retro",
     "Musical","Rock & Roll","Hard Rock","Folk","Folk-Rock",
     "National Folk","Swing","Fast Fusion","Bebob","Latin","Revival",
     "Celtic","Bluegrass","Avantgarde","Gothic Rock","Progressive Rock",
     "Psychedelic Rock","Symphonic Rock","Slow Rock","Big Band",
     "Chorus","Easy Listening","Acoustic","Humour","Speech","Chanson",
     "Opera","Chamber Music","Sonata","Symphony","Booty Bass","Primus",
     "Porn Groove","Satire","Slow Jam","Club","Tango","Samba",
     "Folklore","Ballad","Power Ballad","Rhythmic Soul","Freestyle",
     "Duet","Punk Rock","Drum Solo","Acapella","Euro-House","Dance Hall");
    
     $file=fopen($path, "rb");
    
     if($file)
     {
     fseek($file, 0, SEEK_END);
     fseek($file, -128, SEEK_CUR);
    
     $tag=fread($file, 128);
    
     fclose($file);
     }
     else
     {
     return 0;
     }
    
     if ($tag[0]=='T' && $tag[1]=='A' && $tag[2]=='G')
     {
     $title=substr($tag,3,30);
     $artist=substr($tag,33,30);
     $album=substr($tag,63,30);
     $year=substr($tag,93,4);
     $comment=substr($tag,97,30);
     $type=ord(substr($tag,127,1));
    
     if($type >= 0 && $type <= 125)
     $genre = $genre_array[$type];
     else
     $genre = "none";
    
     if (ord($comment[28]) == 0 && ord($comment[29]) != 0)
     {
     $track = ord($comment[29]);
     $comment[29] = "\0";
     }
     else
     {
     $track = 0;
     }
    
    
     return sprintf("%s-%s-%s-%s-%s-%s-%s",$title, $artist, $album, $year, $comment, $genre, $track);
     }
     else
     {
     return 0;
     }
     }
    
     //Exemple d'utilisation/
    
     $path = "1.mp3";
     $tag = ReadTag($path);
    
     if($path == 0)
     print("Lecture du tag impossible");
     else
     {
    
     list($title, $artist, $album, $year, $comment, $genre, $track) = explode ("-", $tag);
    
     print($title);
     print("<br>");
     print($artist);
     print("<br>");
     print($album);
     print("<br>");
     print($year);
     print("<br>");
     print($comment);
     print("<br>");
     print($genre);
     print("<br>");
     print($track);
     print("<br>");