Decoding Chinese metadata in mp3 files

pe...@for-wild.org

unread,

Jun 19, 2008, 1:42:50 PM6/19/08

to

Can someone help me decode Chinese metadata in mp3 files?
Here are a couple of mp3 files, one with Chinese and one Ebglish
metadata:
http://www.biophile.org/songs/Chinese/Chinese3/Ye%20Lai%20Xiang.mp3
http://www.biophile.org/songs/17%20The%20Lilac%20and%20the%20Apple.mp3

My script is here, and also pasted below:
http://www.biophile.org/songs/Chinese/playit.cgi
===
#!/usr/bin/perl
print "Content-type: text/html\n\n"; use MP3::Tag;

&get_mp3_tag("Chinese3/Ye Lai Xiang.mp3");
&get_mp3_tag("../17 The Lilac and the Apple.mp3");

sub get_mp3_tag { my($file)=@_;
$mp3 = MP3::Tag->new($file); $mp3->get_tags();

if (exists $mp3->{ID3v1}) {
$title=$mp3->{ID3v1}->title;
$artist=$mp3->{ID3v1}->artist;
$mp3->close();
} else {
$title=$sfil; $artist="unknown";
}

print <<"EOP";

file:$file 
title:$title 
artist:$artist
EOP

}
===

Thanks for any help!

Ben Bullock

unread,

Jun 20, 2008, 9:19:43 AM6/20/08

to

On Thu, 19 Jun 2008 10:42:50 -0700, peter wrote:

> Can someone help me decode Chinese metadata in mp3 files?

If you want to decode Chinese characters into Perl's native format, you
need to

use Encode 'decode';

> Here are a couple of mp3 files, one with Chinese and one Ebglish
> metadata:
> http://www.biophile.org/songs/Chinese/Chinese3/Ye%20Lai%20Xiang.mp3

I got a response

404 Not Found
The requested URL does not exist.

It seems you need an "mp3" in the address:

http://www.biophile.org/songs/Chinese/Chinese3/mp3/

It's a nice song, although I don't understand a word of it.

> http://www.biophile.org/songs/17%20The%20Lilac%20and%20the%20Apple.mp3

This one downloaded OK.

> My script is here, and also pasted below:
> http://www.biophile.org/songs/Chinese/playit.cgi

I don't see any output.

> ===
> #!/usr/bin/perl

It's better to have

use warnings;
use strict;

at the top of your script.

> print "Content-type: text/html\n\n"; use MP3::Tag;

You may also find

use CGI;

useful.

> &get_mp3_tag("Chinese3/Ye Lai Xiang.mp3");
> &get_mp3_tag("../17 The Lilac and the Apple.mp3");
>
> sub get_mp3_tag { my($file)=@_;
> $mp3 = MP3::Tag->new($file); $mp3->get_tags();
>
> if (exists $mp3->{ID3v1}) {
> $title=$mp3->{ID3v1}->title;
> $artist=$mp3->{ID3v1}->artist;

On the "Totem Movie Player" on Linux the metadata displayed correctly but
I have no idea what encoding they use.

Assuming these are encoded somehow, you would do something like

$artist = decode ('utf8', $artist);

where you need to replace the string 'utf8' with the name of the encoding
which they're in. Is that what you want to do? The problem then is that
you need to print these out.

> $mp3->close();
> } else {
> $title=$sfil; $artist="unknown";
> }
>
> print <<"EOP";
> 
> file:$file 
> title:$title 
> artist:$artist
> EOP
>
> }
> ===

You probably should also print out some html tags somewhere like

CGI.pm can do all this for you, so I recommend investigating that.

pe...@for-wild.org

unread,

Jun 20, 2008, 12:36:27 PM6/20/08

to

Sorry, I moved the mp3 file temporarily, causing the scrirpt to abort.
Yes the metadata do show up correctly on Linux, and also on Mac and
Windows,
so those operating systems know how to decode the metadata.
I did play with some decoding schemes, including 'gb2312-raw',
but this gives me just one Chinese character, not three,
and an incorrect one. The updated script is:
===
#!/usr/bin/perl
print "Content-type: text/html\n\n"; use MP3::Tag; use Encode;

&get_mp3_tag("Chinese3/Ye Lai Xiang.mp3");
&get_mp3_tag("../17 The Lilac and the Apple.mp3");

sub get_mp3_tag { my($file)=@_;
$mp3 = MP3::Tag->new($file); $mp3->get_tags();

if (exists $mp3->{ID3v1}) {
$title=$mp3->{ID3v1}->title;
$artist=$mp3->{ID3v1}->artist;

$mp3->close();
} else {
$title=$sfil; $artist="unknown";
}

$dtit=decode('gb2312-raw',$title);

print <<"EOP";

file:$file

title:$title($dtit) 
artist:$artist
EOP

}
===

Perhaps it's just a matter of findng out what the proper decoding is?
BTW, even if you don't understand what she is singing, at least you
should be able to hum along with the "Ye Lai Xiang" refrain.

Peter

Ilya Zakharevich

unread,

Jun 20, 2008, 5:17:22 PM6/20/08

to

[A complimentary Cc of this posting was sent to

<pe...@for-wild.org>], who wrote in article <ed407ec1-08c4-461b...@j33g2000pri.googlegroups.com>:

> sub get_mp3_tag { my($file)=@_;
> $mp3 = MP3::Tag->new($file); $mp3->get_tags();
>
> if (exists $mp3->{ID3v1}) {
> $title=$mp3->{ID3v1}->title;
> $artist=$mp3->{ID3v1}->artist;
> $mp3->close();
> } else {
> $title=$sfil; $artist="unknown";
> }

Why not use the documented
$title=$mp3->title;
$artist=$mp3->artist;
and
$title = $sfil unless defined $title and length $title;
etc;

then play with MP3TAG_DEFAULT_V1_DECODE etc (if you know the stuff
comes from v1)...

Ilya

pe...@for-wild.org

unread,

Jun 25, 2008, 2:48:40 PM6/25/08

to

On Jun 20, 4:17 pm, Ilya Zakharevich <nospam-ab...@ilyaz.org> wrote:
> [A complimentary Cc of this posting was sent to
>

> <pe...@for-wild.org>], who wrote in article <ed407ec1-08c4-461b-9510-e25e0baf8...@j33g2000pri.googlegroups.com>:
>
> > sub get_mp3_tag { my($file)=@_;
> > $mp3 = MP3::Tag->new($file); $mp3->get_tags();
>
> > if (exists $mp3->{ID3v1}) {
> > $title=$mp3->{ID3v1}->title;
> > $artist=$mp3->{ID3v1}->artist;
> > $mp3->close();
> > } else {
> > $title=$sfil; $artist="unknown";
> > }
>
> Why not use the documented
> $title=$mp3->title;
> $artist=$mp3->artist;
> and
> $title = $sfil unless defined $title and length $title;
> etc;
>
> then play with MP3TAG_DEFAULT_V1_DECODE etc (if you know the stuff
> comes from v1)...
>
> Ilya

Yes, the $title=$mp3->title; worked.
The other thing I need to tweek was the charset to have the output
show properly on the web,
I wound up using "Content-type: text/html; charset=utf-8\n\n"

The script is now at:
http://www.biophile.org/songs/Chinese/playme.cgi

Thanks for yout help!

Peter