Linux MP3 CD Burning mini-HOWTO

Greg Wierzchowski

greg@draxen.org

2001-05-29
Revision History                                                             
Revision 2.0            2002-04-26             Revised by: GW                
Divided into two sections: existing material to section "audio", new section 
"data" on data CDs. Misc. additions.                                         
Revision 1.5            2001-11-19             Revised by: GW                
Fixed omission in Disc-At-Once burning section.                              
Revision 1.4            2001-11-17             Revised by: GW                
Added Disc-At-Once burning section.                                          
Revision 1.3            2001-09-02             Revised by: GW                
Added another example of decoding MP3 files with lame.                       
Revision 1.2            2001-07-12             Revised by: GW                
Minor layout changes; Added Translations subsection into Credits.            
Revision 1.1            2001-06-12             Revised by: GW                
Minor cleanup; Regexp fix for MP3 to WAV name conversion example.            
Revision 1.0            2001-05-29             Revised by: GW                
Initial Release.                                                             


A complete recipe for creating audio and data CDs from MP3 files.

-----------------------------------------------------------------------------
Table of Contents
1. Introduction
    1.1. Copyright and License
   
   
2. Audio CDs
    2.1. Preparing the Tracks
    2.2. Burning Your CD
    2.3. Burning a DAO CD
    2.4. Software
   
   
3. Data CDs
4. Credits
    4.1. Translations
    4.2. Other Credits
   
   

1. Introduction

This mini-HOWTO was created because of my experience with burning music CDs
and lack of some specific information about sound normalization on the
Internet. I usually burn music CDs as a mix - different songs from different
sources.Very often volume level between songs varies greatly. This is the
first obstacle. Second, many of the files on the Internet are not
CD-compatible (16 bit, stereo, 44.1 kHz) and have to be converted. There are
many programs to burn music CDs from MP3 files, and many of them do the
conversion transparently. But I haven't seen a single tool that also
normalizes the volume, so that's why I worked out my own CD-burning recipe.

This HOWTO is just about one thing - putting MP3 music on a CD, so that you
can listen to it. For in-depth information about MP3 files, please look at 
The Linux MP3 HOWTO by Phil Kerr, located at [http://www.tldp.org/HOWTO/
MP3-HOWTO.html] http://www.tldp.org/HOWTO/MP3-HOWTO.html. For information
about CD creation in general as well as CD burners, refer to CD-Writing-HOWTO
by Winfried Trümper, available at [http://www.tldp.org/HOWTO/
CD-Writing-HOWTO.html] http://www.tldp.org/HOWTO/CD-Writing-HOWTO.html. 

I'm assuming you wish to burn a CD with the collection of songs you obtained
from different sources, all varying quality, but you want to get the
best-sounding CD possible. This mini-HOWTO outlines the steps that may help
you.
-----------------------------------------------------------------------------

1.1. Copyright and License

This document is copyright 2001 by Greg Wierzchowski and is released under
the terms of the GNU Free Documentation License, which is hereby incorporated
by reference. Send feedback to greg.wierzchowski@usa.net.
-----------------------------------------------------------------------------

2. Audio CDs

2.1. Preparing the Tracks

Note Note                                                                    
     All commands assume bash shell                                          

 1. Collect all MP3 files in one directory.
   
 2. If your MP3 files came from DOS/Windows, they may have uppercase
    extensions. You can convert whole names to lowercase or just extensions.
    For everything lowercase do:
         for i in *.[Mm][Pp]3; do mv "$i" `echo $i | tr '[A-Z]' '[a-z]'`; done 
   
    to convert just extensions:
         for i in *.MP3; do mv "$i" "`basename "$i" .MP3`.mp3"; done 
                                                                     
   
 3. If any filenames contain spaces, first convert them to underscores:
         for i in *.mp3; do mv "$i" `echo $i | tr ' ' '_'`; done     
   
 4. Convert them to WAV with the command:
         for i in *.mp3; do mpg123 -w `basename $i .mp3`.wav $i; done 
   
    When decoding 22khz MP3 files the output of mpg123 may be distorted. To
    fix this, use:
         for i in *.mp3; do mpg123 --rate 44100 --stereo --buffer 3072 --resync -w `basename $i .mp3`.wav $i; done 
                                                                                                                   
   
    Mpg123 should be present in any Linux distribution, but if you don't have
    it, get it at [http://www.mpg123.de/] http://www.mpg123.de/.
   
    NOTE I noticed that with some MP3 files mpg123 output was distorted. At
    first I thought that MP3's were bad, but then I checked with another
    player and they sounded OK. So I searched for another MP3 player that
    could write WAV files to disk, and found this one: MAD mp3 decoder at
    [http://www.mars.org/home/rob/proj/mpeg/] http://www.mars.org/home/rob/
    proj/mpeg/. With madplayer, the command line is:
         for i in *.mp3; do madplay -o `basename $i .mp3`.wav $i; done 
   
    There is yet another way to do the conversion. Some MP3 files apparently
    give both mpg123 and madplay trouble with decoding. The lame encoder,
    which has a decoding mode, seems to handle difficult cases very well (
    lame can be found at [http://www.mp3dev.org/mp3/] http://www.mp3dev.org/
    mp3/) :
         for i in *.mp3; do lame --decode $i `basename $i .mp3`.wav; done 
                                                                          
   
    NOTE: The `basename $i .mp3`.wav command replaces MP3 extensions with
    WAV. There are 101 ways to do that, here's the alternative: `echo "$1" |
    sed 's/\.mp3$/.wav/'`
   
 5. Run "file *.wav" and check the output for any files different from 16
    bit, stereo 44100 Hz.
   
 6. If there are files with different characteristics, convert them to the
    above specs. For example, to convert file track01.wav to obtain sample
    rate 44.1 kHz, you could use:
         sox track01.wav -r 44100 track01-new.wav resample           
                                                                     
   
    or, if the above introduces static when converting mono files:
         sox track01.wav -r 44100 -c 2 track01-new.wav               
                                                                     
   
    Sox is so popular, that it's probably installed by default with any Linux
    distribution, and can be obtained from [http://www.spies.com/Sox/] http:/
    /www.spies.com/Sox/. However, the command-line options are somewhat
    cryptic for the casual user (me). Look at [http://www.spies.com/Sox/
    sox.tips.html] http://www.spies.com/Sox/sox.tips.html for some tips on
    usage.
   
 7. Normalize your WAV files, to avoid drastic differences in volume levels.
    I use a program by Chris Vaill (<cvaill@cs.columbia.edu>), called 
    normalize - it can be obtained from [http://www.cs.columbia.edu/~cvaill/
    normalize/] http://www.cs.columbia.edu/~cvaill/normalize/
   
    I use the following syntax (-m is for mix mode, where all files should be
    as loud as possible):
         normalize -m *.wav                                          
   

-----------------------------------------------------------------------------
2.2. Burning Your CD

There are many programs to create CDs from WAV files. I use cdrecord for
command-line burning and XCDROAST for gui. For cdrecord, you have to know
what SCSI device your CD-writer is. If you're using ATAPI writer, use SCSI
emulation (kernel module ide-scsi). Let's assume, that your ATAPI cdwriter is
on the second IDE bus as a master. Thus, it will have /dev/hdc device file.
To instruct the kernel that you want to treat it as a SCSI device, add the
following line to /etc/lilo.conf:
     append=" hdc=ide-scsi"                                                  

Also, if your kernel doesn't automatically load ide-scsi module, add insmod
ide-scsi into your rc.local (or equivalent) file. Once you have our CD-writer
recognized as a SCSI device, run cdrecord --scanbus to find out what's the
"dev" parameter to cdrecord. On my system, the output looks like the
following:
     scsibus1:                                                               
     1,0,0 100) 'IOMEGA ' 'ZIP 250 ' '51.G' Removable Disk                   
     1,1,0 101) 'HP ' 'CD-Writer+ 7100 ' '3.01' Removable CD-ROM             

So, the cdrecord command line will contain dev=1,1,0 to specify the device.
Here is the complete command on my system:
     cdrecord dev=1,1,0 -eject speed=2 -pad -audio *.wav                     

Note NOTE                                                                    
     The -pad argument is neccessary, because all audio tracks on the CD must
     be adjusted for the proper data length, which is not always the case    
     with mp3 files.                                                         
-----------------------------------------------------------------------------

2.3. Burning a DAO CD

DAO, Disc-At-Once, is as of now the only method for burning a CD without a
2-second pause between the tracks. It's useful for burning party mixes. The
program for burning CDs in DAO mode is cdrdao, available from SourceForge,
[http://sourceforge.net/projects/cdrdao/] http://sourceforge.net/projects/
cdrdao/.

The cdrdao program uses description files called TOC (Table Of Contents, of
course). There are two ways to create such file. First is to use a shell
script, distributed with cdrdao source (in contrib directory, called 
generate_toc.sh. It takes a list of .wav files as an argument and produces a
cd.toc file. Second way is to simply create such file yourself in a text
editor of your choice. Here is a self-explanatory example:
CD_DA                                                                        
                                                                             
TRACK AUDIO                                                                  
AUDIOFILE "mix-01.wav" 0                                                     
                                                                             
TRACK AUDIO                                                                  
AUDIOFILE "mix-02.wav" 0                                                     
                                                                             
TRACK AUDIO                                                                  
AUDIOFILE "mix-03.wav" 0                                                     
                                                                             
TRACK AUDIO                                                                  
AUDIOFILE "mix-04.wav" 0                                                     
                                                                             
TRACK AUDIO                                                                  
AUDIOFILE "mix-05.wav" 0                                                     

The 0 (zero) after the wave filename means start from the beginning of the
file. There can be a second number providing the length (time) of file to
record. The xcdroast creates similar TOC files, there are also examples in
testtocs directory of cdrdao source.

The cdrdao by default uses the device /dev/cdrecorder, which should be a link
to the cdwriter device. Assuming your cd recorder device file is /dev/scd0,
create the link (as root) as follows:
ln -s /dev/scd0 /dev/cdrecorder                                              

Then, assuming that the TOC file is named cd.toc the command to burn the cd
is simply:
cdrdao write cd.toc                                                          
-----------------------------------------------------------------------------

2.4. Software

There are some programs available, that can automate the process of creating
CDs from MP3 files. Here is arbitrarily selected list:

  * burnmp3 - Program to automate burning with DAO method. [http://
    richardsnow.bizland.com/burnmp3/] http://richardsnow.bizland.com/burnmp3
    /.
   
  * mp32dao - a script from cdrdao distribution, in the contrib directory.
    [http://cdrdao.sourceforge.net/] http://cdrdao.sourceforge.net/.
   

-----------------------------------------------------------------------------
3. Data CDs

Note Note                                                                    
     This section is a work in progress, you're looking at initial, very     
     sparse version.                                                         

With increasing popularity of CD/MP3 players burning data CDs for listening
purposes become practical. The advantage is definitely being able to squeeze
ten times more music onto one CD (a very approximate figure). As far as MP3
data CD-s, they're just a regular, standard data CD's (ISO9660) with MP3
music as regular files. All MP3-CD players I know accept CD-s with
directories in them, and I usually burn CD with Joliet extension and they
work just fine. So to burn such a CD under linux, you first need to create an
ISO image an then burn it on the CD as in the example below:
mkisofs -J -o /tmp/mymp3s.iso /home/greg/mp3s/                               
cdrecord dev=1,0,0 speed=16 /tmp/mymp3s.iso                                  

That's it!

I have yet to research ability to normalize mp3 files directly - however I
believe it always involves decompressing, normalization and then
re-compressing the file, which introduces quality loss. Stay tuned!
-----------------------------------------------------------------------------

4. Credits

Special thanks to all the people who contribute to the Linux community and
who made this HOWTO possible.
-----------------------------------------------------------------------------

4.1. Translations

  * Im Eunjea - Translated this document to Korean, URL is [http://
    kltp.kldp.org/eunjea/mp3_burning/] http://kltp.kldp.org/eunjea/
    mp3_burning/.
   
  * Mendel L Chan - Translated this document to Chinese, URL is [http://
    www.linux.org.tw/CLDP/mini/MP3-CD-Burning/] http://www.linux.org.tw/CLDP/
    mini/MP3-CD-Burning/.
   
  * Chie Nakatani - Translated this document to Japanese, URL is [http://
    www.linux.or.jp/JF/JFdocs/MP3-CD-Burning/index.html] http://
    www.linux.or.jp/JF/JFdocs/MP3-CD-Burning/index.html.
   

-----------------------------------------------------------------------------
4.2. Other Credits

  * Greg Ferguson - Initially converted this document from HTML to SGML.
   
  * Rob Russell - Corrected my name conversion example.
   
  * Terry Davis - Suggested submitting my HOWTO to linuxdoc.
   
  * Chris Vaill - Created normalize program.
   
  * Jamie Kellogg - Submitted a solution to decode with lame for troublesome
    files.
   
  * Tom Panning - Submitted a tip for the conversion of mono files with sox.
   
  * Adam Buckley - Submitted an idea about files with uppercase extension.
   
  * Ilia Lobsanov - Submitted options for mpg123 decoding 22kHz files.
   

