Contents

  1. Introduction
  2. What is a CD burner?
  3. Buying a CD Burner
  4. Setting up your CD burner
  5. Creating a data CD
  6. Creating a music CD
  7. Using a GUI
  8. Advanced topics
  9. Warnings
  10. Summary of command lines
  11. References

Introduction

If you want to burn CDs under Linux, then read the CD-Writing HOWTO. If you still have questions, then move on to the CD recordable FAQ, a comprehensive list of common questions. I shall refer to these as the "HOWTO" and the "FAQ" respectively. This document is meant to be a summary of some of the information in the HOWTO and FAQ, a quick reference so that you don't have to go to the full document all the time, and some notes on other useful hints and tips. A lot of this information I have simply copied straight from the relevant HOWTOs.

What is a CD burner?

CD Writers

CD-Writers have a more powerful laser than normal CD readers. This laser is capable of burning pits inside special CD-Recordables (CD-R discs). CD Writers can read data and audio discs just like a regular CD ROM drive.

CD Re-Writers (CD-RW)

A CD Re-Writer is essentially a CD Writer with a more powerful laser. They can record CD-Rs exactly as a CD Writer and they can also handle CD-RW discs. CD-RW discs are different to CD-Rs. Instead of burning pits in the disc, the laser causes a phase change in the CD medium. The change may be reversed to erase the data. However most CD-RW discs are only able to be read on another CD Re-Writer because they need a more powerful laser to read them.

SCSI vs IDE/ATAPI

Roughly speaking SCSI and IDE are the two main ways for your external devices (hard disc, CD-ROM etc.) to talk to your motherboard. SCSI is typically faster and easier to use, while IDE/ATAPI is cheaper. All CD burners run from SCSI commands, so when you install the CD writer you must either have a SCSI one, or install the ATAPI-SCSI emulation driver. For more information there are some notes included with the cdrecord documentation.

Buying a CD Burner

Internal vs External

An external drive is potentially better because you have the option of moving it between machines, but unless you know lots of people with SCSI cards, or have a parallel port burner, then this isn't much of an advantage. It used to be better to get an external drive because of the heat, but the technology has improved to the point where that isn't necessary.

SCSI vs IDE vs parallel vs USB

USB CD-writers are currently not supported at all. Apart from that you can safely assume that most newer IDE/ATAPI- and SCSI-writers work under Linux. It is possible to connect drives via the parallel port, but I know nothing about it. Read http://www.torque.net/parport/parscsi.html to learn more about this option.

Which is better? SCSI is probably easier to set-up, used to be less prone to buffer underruns and produced higher quality audio discs (IDE has improved). It also gives you the option of doing a direct disc-to-disc copy. However it is more expensive.

What speed?

As fast as you can afford. A driver rated at "1x" will write the disc at the normal speed; i.e. it will take 74 minutes to write a full disc. One rated at "2x" will take half that time and so on. Waiting over an hour only to find you have burned a coaster is quite off-putting. Fifteen minutes (at 4x), on the other hand, is bearable.

Which writer?

The FAQ has a very good list of CD-Writers and their merits, including a summary of the "best" drives. You must make sure you get a supported drive - see the HOWTO for a summary or go here for a complete list.

Setting up your CD burner

For a full description see the HOWTO.

SCSI

If your system isn't SCSI, then you need a SCSI card as well. I have a TEKRAM D-390-UW which is not too expensive (i.e. a third the price of the equivalent Adaptec) and performs well. The basic steps are:
  1. Plug in the hardware (make sure your cable is terminated).
  2. Set up the kernel module for your card. There used to be a list of which driver corresponded to each card, but I can't find it. I have a line in /etc/conf.modules that reads alias scsi_hostadapter ncr53c8xx which tells the kernal to load the ncr53c8xx driver for my card.
  3. Find out where on your SCSI bus your drive is. You can run, for example, 
    cdrecord -scanbus
    and I get lines like: 
     0,1,0     1) 'TEAC    ' 'CD-R55S         ' '1.0L' Removable CD-ROM
    This says my drive is on bus 0, with SCSI id 1 and Logical Unit Number (LUN) 0. You need this information for later.

IDE

  1. Plugging in the hardware is straightforward; just put it in your drive cage and plug in the cable and power supply.
  2. To use an IDE writer you need the ide-scsi compatibility kernel module. You have to be careful to set this up so that it only accesses the drives you want to be accessed as SCSI drives, but it can be done. Also, please note that when you have this module running it may still be used to access your existing CD ROM drive. The difference is that you access it via the SCSI devices /dev/sg* or /dev/scd*, rather than the IDE devices /dev/hd*. For more information see cdrecord/README.ATAPI
  3. Once the ide-scsi driver is installed, proceed as for SCSI.

Getting the software

The main software components you need are
cdrecord
A command line tool for recording CDs.
cdda2wav
A command line tool for reading audio data from CDs. It is included in the cdrecord package.
mkisofs
A command line tool for creating the filesystem images needed to record data CDs. This is also included with cdrecord, and has merged with mkhybrid for making hybrid filesystems.
cdparanoia
A command line tool for copying audio data from audio CDs. This will perform "paranoid" copying - which includes scratch repair, so-called jitter correction and more.
mpg123
If you want to record mpegs to CD this utility will convert mp3 files to the correct format (as well as play them...).
sox
A command line utility to convert between various audio formats.
play
A frontend for sox that lets you play any of the formats that sox understands - usually included with sox.
These are the basic command line utilities that you need. Most of the GUIs use one or more of these to provide their functionality. You can do most of what you need with these tools, but for trickier features you either have to understand what you are doing very well, or use one of the GUIs. More about them later.

Creating a data CD

Creating the filesystem image

You could write your file system directly to the CD and make a perfectly good disc. However you would only be able to read it under Linux, and more than likely your CD-ROM is not expecting to read an ext2fs filesystem on a CD. Instead you use a tool such as mkisofs. This will take a snapshot of a given directory tree and create a binary image that corresponds to an iso9660 or HFS filesystem.

mkisofs has a very long list of complicated options and I always use xcdroast to create my disc images. However if you want to include all files from a single directory, /home for example, then you can simply type: 

mkisofs -r -o cd_image.raw /home
and this will generate the file cd_image.raw containing your data. The maximum size a data image can be is about 650Mb. The -r option enables the Rock Ridge extensions to iso9660 for long filenames and also sets all files to be readable so that anyone can read the disc. If you want Rock Ridge without anonymity, then use -R - however if you try to read the CD generated on another Linux system with different user id numbers, then you will only be able to read it as root.

Testing the image

If you have loopback device support (on by default in most distributions), then you can test your image by mounting it. To mount the file you have just created on /mnt/tmp run 
mount -t iso9660 -o ro,loop=/dev/loop0 cd_image.raw /mnt/tmp
You may then change to the directory /mnt/tmp and you should see a copy of your /home directory sitting there. When you are finished move out of the directory and type umount /mnt/tmp to unmount it.

Burning your first CD

If you haven't already tried, it's a good time for the command 
cdrecord -scanbus
(see above). This will tell you where on your SCSI bus the burner is. I get: 
 0,1,0     1) 'TEAC    ' 'CD-R55S         ' '1.0L' Removable CD-ROM
and so I use the 0,1,0 for the dev argument to cdrecord.

If you have never burnt a CD before or if your system is loaded, then you should always do a test run by calling cdrecord in "dummy" mode. In this mode cdrecord runs exactly as normal, except that it doesn't turn on the laser. That way you can check to see if you are likely to suffer from buffer underrun, i.e. your computer cannot get the data to the burner fast enough. Test cdrecord in dummy mode with: 

cdrecord  -v  -dummy  speed=4  dev=0,1,0  -data  cd_image.raw
Record the image with: 
cdrecord  -v  speed=4  dev=0,1,0  -data  cd_image.raw
Replace the speed=4 argument with the speed of your burner.

Testing the CD

The quickest way to test the CD is to mount it and look at what's there. If your CD writer is /dev/scd0, then you can mount it at /mnt/cdrom with 
mount -t iso9660 /dev/scd0 /mnt/cdrom
Now, ls /mnt/cdrom should give you a listing of your files.

If you want a more detailed check, then get star by the author of cdrecord. This is "s-tar" for "SCSI Tape Archiver", a version of tar written specifically for SCSI devices. It has a long list of features for verification and is quicker and easier than using diff -r. If you used mkisofs with -r, then you can check the filesystem with 

(cd /home; star -cPM .)|(cd /mnt/cdrom; star -diff -v \ 
         diffopts=\!times,\!perm,\!uid,\!gid,\!uname,\!gname)
otherwise you can just use 
(cd /home; star -cPM .)|(cd /mnt/cdrom; star -diff -v diffopts=\!times)
For more information see cdrecord/README.verify.

Creating a music CD

Getting the audio data from a disc

The encoding for audio discs is completely different to that for data discs. The two main programs for getting audio data from a CD onto your hard disc in a useable form are cdda2wav written by the author of cdrecord, and cdparanoia. The first is much faster and produces .wav files which cdrecord understands, while the second can produce much higher quality copies either as raw data (which cdrecord understands) or as .wav files. I always use cdparanoia. Some sample command lines follow.

Get cdparanoia to read the disk in /dev/scd1 and list its table of contents:

cdparanoia -d /dev/scd1 -Qv

Read the whole of track n and write the data to the file track_n.cdr:
cdparanoia -d /dev/scd1 n track_n.cdr

Read the whole disk a track at a time, putting each track into a separate file track#.cdr:
cdparanoia -v -d /dev/scd1 -B 1- cdr
Warning: CD readers, like computers, are inconsistent in the way they return the data, big or little endian. Read the documentation for full details, but here is a quick test. Read a track from your CD using cdparanoia and then try to play it with play track01.cdr. If all you hear is hissing, then the data is coming out in the wrong byte order. To force cdparanoia to return big endian data use the -R flag, and to force little endian use the -r flag. One of these should produce a track that play will play. If you burn the disc and all you hear is hissing, then this failed and you still have the wrong byte order. Try it again using the -swab flag with cdrecord. I need to force big endian with my setup, so my commands look like:
cdparanoia -v -d /dev/scd0 -R -B 1- cdr
and then I don't need to use the -swab flag with cdrecord.

Using mp3s for your audio data

MP3 files are just another way of encoding audio data. They can be converted to a form suitable for recording with mpg123, which is also an mp3 player. If you have the mp3 files you want to convert in the current directory, then this will do the trick: 
for file in *.mp3
do
	mpg123 --cdr - $file > $file.cdr
done
This will convert files like my_music.mp3 and produce my_music.mp3.cdr. I'm sure you can come up with something more sophisticated, but this shows how to use mpg123.

Other audio formats

If you have audio files in different formats, then you can use sox to convert them to .wav or .cdr files. sox understands a large variety of audio formats; see the documentation for a full list. If you are interested in the format of various audio files, then you will be interested in the Audio File Format FAQ which is maintained by the current maintainer of sox.

Recording an audio CD

To record audio files track01.cdr track02.cdr ... in that order you can use:
 cdrecord -v speed=4 dev=0,1,0 -audio track*.cdr

Note that this relies on the alpha-numeric ordering of the shell's wildcard expansion of "track*.cdr". It doesn't hurt to do /bin/ls track*.cdr first to check that the files come out in the correct order.

Using a GUI

The two graphical interfaces I have experience with are X-CD-Roast and gcdmaster. Some tasks, particularly creating data images with mkisofs, are sufficiently complicated that a GUI is very useful.

X-CD-Roast

This is written in tcl/tk and provides functionality for creating data and audio disc images, and for recording and verifying the images. It is an independent frontend for cdrecord and friends. The strong point of X-CD-Roast for me is that it makes creating data images very simple. The only fault for me is that it is very slow. It is currently coming to the end of a complete re-write using the gtk libs. This makes it a lot faster and easier to use. It also will have much more functionality - in particular it will make mixed mode CDs, multisession CDs and so on. I would still recommend the current version (xcdroast-0.96ex2-4), at least to start with, because there is little or no documentation on how to use the newest alpha version (xcdroast-0.98alpha6).

Gcdmaster

Gcdmaster is also written with the gtk libraries. It is a frontend for cdrdao and is intended primarily for creating audio CDs. It uses the cdparanoia libraries for saving data from a CD, and cdrdao for recording the data onto the CD. My main use for this is to record an audio CD in "Disc At Once" made.

Advanced topics

Disc At Once (DAO) vs Track At Once (TAO)

Most, if not all, CD writers force a two second gap between each track. So if you write your audio tracks in TAO mode (this is the standard) then you have to live with this gap. It can be a real pain if you have recorded a live CD of your new band, but you want to put track marks in between the tracks so that your CD player will see them. The other problem is that this can cause clicks and pops (particularly with IDE writers) in the gap. The examples above were for TAO mode.

Not all writers support DAO mode, but if yours does then you can record the disc in one shot without the gaps. In order to put the track marks in you need to write a table of contents (TOC) that describes where these occur. You can do all this with gcdmaster (cdrecord has a flag for DAO, but no explanation how to use it or specify the TOC etc.). Suppose your live recording is in one huge file, image.bin, and you want to make the TOC. It should be a separate file, image.toc, and look something like this: 

CD_DA
 
// Track 1
TRACK AUDIO
NO COPY
NO PRE_EMPHASIS
TWO_CHANNEL_AUDIO
FILE "/images/cdr/image.bin" 0 04:12:59 
 
// Track 2
TRACK AUDIO
NO COPY
NO PRE_EMPHASIS
TWO_CHANNEL_AUDIO
FILE "/images/cdr/image.bin" 04:12:59 03:29:22
START 00:01:73
The two times after the FILE argument are the start and length of the track. The START argument after track2 (and higher) is the length of the pre-gap. You can cut this to 00:00:00 for your live CD.

Gcdmaster will also read a complete CD into one large file, and write the TOC at the same time.

Mixed Mode Cds: "CD-Plus"

Mixed mode CDs have both audio and data files on them; "CD Plus" refers to the special case where the first session is audio tracks and the second session is a data track. Many music CDs are CD plus discs. You don't notice anything special if you put it in your CD player, but if you read it on your computer, then you can also see the data track. The quick and dirty way to write these is just to specify which tracks are audio and which are data: 
 cdrecord -v speed=4 dev=0,1,0 -audio track*.cdr -data image.raw
Note that most CD players can only read audio tracks in the first session, and will see data tracks as gaps. For the "correct" way to write CD Plus discs read cdrecord/README.cdplus and for an explanation of "sessions" see the next section.

Multisession CDs

Instead of writing your CD all at once you may do it in several sessions. There are several warnings that come with this, however: For more information on creating multi-session discs see cdrecord/README.multi.

For an example, suppose you have the following directory structure in your filesystem: 

/home/     
     alice/
     fred/
     jane/
     joe/
     ...
/var/www/
     httpd/
     ...
and you want to make a disc that has directories 
alice/
fred/
httpd/
jane/
joe/
...
and for some reason you want to write the stuff in /home in one session, then the stuff in /var/www in the next session.
  1. Create the first data image: mkisofs -r -o image1.raw /home
  2. Record it: cdrecord -v speed=4 dev=0,1,0 -multi -data image1.raw Note the flag to say that this is part of a multisession recording.
  3. Create the next data image (this is the tricky part):
    1. Find where the free space on the CD-R begins with cdrecord -msinfo dev=0,1,0 The output should be two numbers separated by a comma e.g.: 0,204562
    2. Create the data image:
      mkisofs -r -o image2.raw -C 0,204562 -M /dev/scd0 /var/www
      where the argument of the -C flag is the output of the previous command, and the argument of the -M flag is a device that may be used to mount the cd writer.
  4. Record the next data image: cdrecord -v speed=4 dev=0,1,0 -multi -data image2.raw
  5. When you are finished writing images, either write the last one without the -multi flag, or finish with cdrecord -fix

Warnings

Some things to beware of when writing CDs.

Summary of command lines

mkisofs

Create a data image of the contents of /directory using Rock-Ridge extensions with anonymity 
mkisofs -r -o image.raw /directory
Create a data image of the contents of /directory using Rock-Ridge extensions, but preserving the original permissions and ownership 
mkisofs -R -o image.raw /directory
Create a second data image based on a previous one: 
mkisofs -r -o image2.raw -C 0,204562 -M /dev/scd0 /directory2

mount

Mount a data image on /mnt/tmp to test it 
mount -t iso9660 -o ro,loop=/dev/loop0 image.raw /mnt/tmp
Mount the disc in your cd reader/writer corresponding to /dev/scd0 
mount -t iso9660 /dev/scd0 /mnt/cdrom
Unmount the file/device/whatever that is mounted on /mnt/tmp 
umount /mnt/tmp

cdparanoia

Get cdparanoia to read the disk in /dev/scd1 and list its table of contents: 
cdparanoia -d /dev/scd1 -Qv
Read the whole of track n and write the data to the file track_n.cdr 
cdparanoia -d /dev/scd1 n track_n.cdr

Read the whole disk a track at a time, putting each track into a separate file track#.cdr 
cdparanoia -v -d /dev/scd1 -B 1- cdr

mpg123

Convert the mp3 file boring.mp3 to a raw audio file 
mpg123 --cdr - boring.mp3 > boring.cdr

cdrecord

Test cdrecord in dummy mode 
cdrecord  -v  -dummy  speed=4  dev=0,1,0  -data  image.raw
Record the image 
cdrecord  -v  speed=4  dev=0,1,0  -data  image.raw
Record audio files track01.cdr track02.cdr ... in that order 
 cdrecord -v speed=4 dev=0,1,0 -audio track*.cdr
Create a "mixed-mode" CD 
 cdrecord -v speed=4 dev=0,1,0 -audio track*.cdr -data image.raw
Create a multi-session CD 
cdrecord -v speed=4 dev=0,1,0 -multi -data image1.raw
Finish (fixate) a CD only necessary if the last session was written with -multi 
cdrecord -fix

star

Test a disc written with Rock-Ridge extensions and anonymity whose contents came from /directory 
(cd /directory; star -cPM .)|(cd /mnt/cdrom; star -diff -v \ 
diffopts=\!times,\!perm,\!uid,\!gid,\!uname,\!gname)
Test a disc written with the original permissions and ownership 
(cd /home; star -cPM .)|(cd /mnt/cdrom; star -diff -v diffopts=\!times)

References

CD Writing HOWTO

The definitive HOWTO for CD recording. Read it locally in a single document or in parts. The newest version of the document can be found at http://www.guug.de/~winni/linux/cdr/html/. The author has other useful documents and links at http://www.guug.de/~winni/linux/.

cdrecord homepage

The main homepage for cdrecord is at http://www.fokus.gmd.de/research/cc/glone/employees/joerg.schilling/private/cdrecord.html. Cdrecord includes the programs cdda2wav, mkisofs and mkhybrid. There are many useful CD related links on this page. The documentation may be read locally.

cdparanoia

cdparanoia is a command line tool for copying audio data from audio CDs. This will perform "paranoid" copying - which includes scratch repair, so-called jitter correction and more. The homepage: http://www.xiph.org/paranoia/

CD recordable FAQ

The definitive CD FAQ. Read it locally or at its home site, http://www.fadden.com/cdrfaq/ . There is also a single page version (but it is huge).

CD-ROM HOWTO

Kernel HOWTO

sox homepage

Sox is almost the ultimate sound file format conversion utility. The homepage is at http://home.sprynet.com/~cbagwell/sox.html. The author also maintains the Audio File Format FAQ.

mpg123 homepage

mpg123 is an mp3 decoder/player - it claims to be the fastest available for unix-type systems. The homepage is at http://mpg123.org/.

xcdroast homepage

A good general purpose frontend for cdrecord, cdparanoia and mkisofs. The homepage is at http://www.fh-muenchen.de/rz/xcdroast/ and the alpha version may be found at http://www.fh-muenchen.de/home/ze/rz/services/projects/xcdroast/xcdr098/

gcdmaster homepage

Gcdmaster is a front end for cdrdao and may be used to create discs in "Disc-At-Once" mode. It also lets you edit the table of contents for a CD and has several other useful features for audio CDs. Gcdmaster can be downloaded from the cdrdao homepage at http://cdrdao.sourceforge.net/ or from rpmfind.net.

From the CD Writing HOWTO:

"If to smoke you turn I shall not cease to fiddle while you burn." (Roman emperor Nero about burning his own classic-CDs, AD64. He misunderstood it completely and burned Rome down.)

Copyright

Are you kidding? I copied most of this straight from the documents listed above. It does come with a warning, though:

The author disclaims all warranties with regard to this document, including all implied warranties of merchantability and fitness for a certain purpose; in no event shall the author be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use of this document.

Short: read and use at your own risk. No money-back guarantee.

Robert Judd, Sunday 29 October 2000.