ID3
Using the ID3 extension you might be interested in some more functionality for working with MP3-files that is missing in the PHP C-modules.
Such as extracting for instance the first 10 seconds of a song, merging MP3 files, calculating the exact length of the MP3 file.
The following class in pure PHP is available for that:
http://www.sourcerally.net/Scripts/20-PHP-MP3-Class
ID3 関数
目次
- id3_get_frame_long_name — ID3v2 フレームの長い名前を取得する
- id3_get_frame_short_name — ID3v2 フレームの短い名前を取得する
- id3_get_genre_id — ジャンルの ID を取得する
- id3_get_genre_list — 使用可能なジャンルの一覧を取得する
- id3_get_genre_name — ジャンル ID に対応する名前を取得する
- id3_get_tag — ID3 タグに含まれるすべての情報を取得する
- id3_get_version — ID3 タグのバージョンを取得する
- id3_remove_tag — 既存の ID3 タグを削除する
- id3_set_tag — ID3 タグに格納されている情報を更新する
add a note
User Contributed NotesID3 関数
regindk at gmail dot com
29-Dec-2006 11:54
29-Dec-2006 11:54
jbwalker at telus dot net
19-Nov-2006 08:37
19-Nov-2006 08:37
Oops! The code below was inelegant to begin with and stripped down further to limit space taken up here, contains one serious bug: the assumption that the input tag header (first 10 bytes) will do for output. This likely works fine if your own finely tuned tags take up less real estate than MS's bloated headers but not if you read mp3s from a product that sets a tag length less than the length of your own header! A simple fix for this is to insert the code:
$tagLen = 1024; # or whatever you like >your actual
$Header = substr($Header,0,6).setHexTagLen($tagLen);
after the line '$music = etc.
The setHexTagLen can be figured out from the calcDecTagLen but here's some sample code.
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;
}
jbwalker at telus dot net
16-Nov-2006 04:58
16-Nov-2006 04:58
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.
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,$tagLen+10,-128);
# Can use input Header for output but you may
# wish to change the output filename for testing
file_put_contents($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");
wmd at wazee dot org
11-Jul-2004 06:31
11-Jul-2004 06:31
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)