ID3 Functions
Table of Contents
- id3_get_frame_long_name — Get the long name of an ID3v2 frame
- id3_get_frame_short_name — Get the short name of an ID3v2 frame
- id3_get_genre_id — Get the id for a genre
- id3_get_genre_list — Get all possible genre values
- id3_get_genre_name — Get the name for a genre id
- id3_get_tag — Get all information stored in an ID3 tag
- id3_get_version — Get version of an ID3 tag
- id3_remove_tag — Remove an existing ID3 tag
- id3_set_tag — Update information stored in an ID3 tag
Коментарии
There are several highly developed id3 reader classes written in php that include id3v2 support, and support for other file formats (not just mpeg & id3). I recommend http://getid3.sourceforge.net/ as well as the id3 reader class integrated in the Zina is not Andromeda project (http://pancake.org/zina.html)Windows XP users may be having trouble with routines provided here and may (as above) only have access to "read" classes. The following very simplified "write" can be used for replacing Windows Media Player file tags, and with care and adjustments, can be used more generally.
<?php
define(_Title,"TIT2");
define(_Artist,"TPE1");
define(_Group,"TPE2");
define(_Album,"TALB");
define(_Genre,"TCON");
define(_TrackNo,"TRCK");
define(_Year,"TYER");
$frames = array(_Album=>"The Ultimate Experience",
_TrackNo=>"1",
_Title=>"All along the watchtower",
_Artist=>"Jimi Hendrix",
_Group=>"",
_Year=>"19xx",
_Genre=>"Rock");
#..........................................
# WRITE ID3 TAGS (Write MP3 [v1, v2]
#..........................................
function writeTags($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($str,30,chr(0)),0,30);
}
# This is a simple example for an mp3 in current folder
writeTags("01-Cognac Blues.mp3");
?>
The setHexTagLen can be figured out from the calcDecTagLen but here's some sample code.
<?php
function setHexTagLen($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;
}
?>