writeTags(\'song_files.mp3\');

                        
define(_Title,"TIT2"); 

define(_Artist,"TPE1"); 

define(_Group,"TPE2"); 

define(_Album,"TALB"); 

define(_Genre,"TCON"); 

define(_TrackNo,"TRCK"); 

define(_Year,"TYER"); 

$frames = array(_Album=>"Album 2", 

_TrackNo=>"1", 

_Title=>"Name Song", 

_Artist=>"Name Artist", 

_Group=>"Name Group", 

_Year=>"2010", 

_Genre=>"Other"); 



#.......................................... 

# WRITE ID3 TAGS (Write MP3 [v1, v2] 

#.......................................... 

function writeTags($mp3) { 

$fl = file_get_contents($mp3); 

$Header = substr($fl,0,10); 

$tagLen = calcDecTagLen(substr($Header,6,4),$tagLen); 

$music = substr($fl,$tagLen+10,-128); 

# Can use input Header for output but you may 

# wish to change the output filename for testing 

$tagLen = 1024; # or whatever you like >your actual 

$Header = substr($Header,0,6).setHexTagLen($tagLen); 

file_put_contents($mp3,mkV2Tag($Header,$tagLen).$music.mkV1Tag()); 

} 

# Create the V2 tag 

function mkV2Tag($Hdr,$tagLen) { 

Global $frames; 

$null = chr(0); 

$nl3 = $null.$null.$null; # 0 bytes for flags and encoding 

$out = ""; 

foreach($frames as $ky=>$val) { 

$n=strlen($val)+1; 

$out.= $ky.mkFrmLen($n).$nl3.$val; 

} 

return $Hdr.str_pad($out,$tagLen,$null); 

} 

# Calculate Tag Length from bytes 6-10 of existing header 

function calcDecTagLen($word) { 

$m = 1; 

$int = 0; 

for ($i=strlen($word)-1;$i>-1;$i--) { 

$int +=$m*ord($word[$i]); 

$m=$m*128; 

} 

return $int; 

} 

# Make the 4 byte frame length value for the V2tag 

function mkFrmLen($int) { 

$hx = ""; 

while ($int>0) { 

$n = $int % 256; 

$hx = chr($n).$hx; 

$int=floor($int/256); 

} 

return str_pad($hx,4,chr(0),STR_PAD_LEFT); 

} 

# Create the 128 byte V1 tag 

function mkV1Tag() { 

Global $frames; 

$tagOut = "TAG". 

adj($frames[_Title]). 

adj($frames[_Artist]). 

adj($frames[_Album]). 

str_pad($frames[_Year],4). 

str_pad(" ",29," "). 

chr($frames[_TrackNo]). 

chr($n); 

return $tagOut; 

} 

# Pad the header to 30 characters 

function adj($str) { 

return substr(str_pad($str,30,chr(0)),0,30); 

} 

function setHexTagLen($int) { 

$n = pow(128,3); 

$intVar = $int; 

$m = ""; 

for ($i=0;$i<4;$i++) { 

$m .= chr(floor($intVar/$n)); 

$intVar = $intVar % $n; 

$n=$n/128; 

} 

return $m; 

} 

////// EXAMPLE 

writeTags('song_files.mp3');