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[comp.publish.cdrom] CD-Recordable FAQ, Part 2/4

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Subject: [3] How Do I...
(1998/04/06)

This is general information about recommended ways to do specific tasks.


Subject: [3-1] How do I copy a CD-ROM?
(2002/12/02)

Just about every piece of CD recording software comes with a CD copier.
In some cases it's a stand-alone extra, in some it's integrated with
other features, and in a few cases the software does nothing else.

Most disc copying software will allow you to make a CD image on a hard
drive that can then be written to multiple CDs.  A few will allow you
to record the same image to multiple CD recorders simultaneously (see
section (3-17)).

It's important to remember that, when copying directly from one CD to
another, the source MUST be faster than the target, and must be
error-free.  If the source pauses or spins down to read a marginal area of
the disc, the target may outrun the source, and the CD-R will only be
useful as a frisbee.  Most programs have a "test write" feature that put
the CD-R device into a mode where it goes through all the motions but
doesn't actually write anything; it's a good idea to do this right before
copying something for the first time.

If you're wondering about copying Mac CD-ROMs on a PC or vice-versa, see
section (3-50).

Some suggestions for software good at copying a variety of discs:

  CloneCD (6-1-49)
    Very good at copying difficult (esp. copy-protected) discs.
  CDRWIN (6-1-7)
    Good at copying discs, also very nice for fancy audio CDs.
  Disc Juggler (6-1-27)
    Can copy to more than one device at a time.
  CDRDAO (6-1-47)
    Runs under a wide variety of operating systems.

For copying simple audio CDs and un-protected CD-ROMs, standard
applications like Nero or Toast will work just fine.

See section (2-4) for more information about copy protection, section
(3-51) for the details on "RAW" reads, and (3-4) for some notes on game
console discs.


Subject: [3-1-1] Why can't I just do a block copy like a floppy?
(1998/04/06)

CDs don't have circular tracks.  They're laid out on a spiral, with
multiple sessions composed of multiple tracks composed of sectors, and the
data in the sectors is interleaved and spread over a large area.  The
sector format is standard, but there's more than one standard.

 "The nice thing about standards is that you have so many to choose from."
 -- Andrew S. Tanenbaum, _Computer Networks_, 2nd ed, p.254

The ability to read certain portions of a CD depends on the CD firmware.
Some CD players aren't capable of understanding multi-session discs or of
reading audio tracks as digital data.  Jitter, described in section (2-15),
is also a problem for most drives.


Subject: [3-2] How do I extract tracks from ("rip") or copy an audio CD?
(2002/12/09)

Start with the CD-DA FAQ [once at http://www.tardis.ed.ac.uk/~psyche/cdda/,
currently missing?]  Take a look at http://come.to/cdspeed to see if your
CD-ROM drive is up to the task.  EAC, from http://www.exactaudiocopy.de/,
is often recommended for extracting ("ripping") audio tracks.

To copy from CD to CD, the source drive needs to support digital audio
extraction, which is rare among older drives but universal in current
models.  Ideally, the copy program will use disc-at-once recording to
produce a duplicate that mimics the original as closely as possible.
As with copying CD-ROMs, you must be able to read data off of the source
drive faster than your recorder is writing.  If you can only extract audio
at 1x, you're not going to be able to do a CD-to-CD copy reliably.

If you're just interested in extracting digital audio, you don't even need
a CD-R unit, just a CD-ROM drive that supports Digital Audio Extraction
(DAE) and some software.  The CD-DA sites noted at the top of this section
list drives that support DAE, have software to evaluate your existing
drive, and have links to several different DAE applications.

Different drives can extract digital audio at different speeds.  For
example, the Plextor 6Plex can extract audio at 6x, while the NEC 6Xi can
only extract at 1x.  Most recent drives extract at well over 20x, which
is about the limit for an IDE drive that doesn't support DMA.

Some CD-ROM and CD-R drives have trouble extracting digital audio at high
speed, so if you're getting lots of clicks and pops when extracting you
should try doing it at a slower speed.  You may also run into trouble if
you try to extract faster than your hard drive can write.  One user found
that he was able to eliminate clicks and pops by defragmenting his hard
drive.  Another found that the Win95 "vcache" fix (section (4-1-2)) solved
his problems.

It should be pointed out that, while digitally extracted audio is an exact
copy of the data on the CD, it's an exact copy as your CD player perceives
it.  Different drives or different runs with the same drive can extract
slightly different data from the same disc.  The differences are usually
inaudible, however.  Some newer drives will report the number of
uncorrectable errors encountered, so you can get a sense for how accurate
the extraction really is.

The quality of the audio on the duplicate CD-R, given a high-quality
extraction, depends mostly on how well your CD player gets along with the
brand of media you're using.  See the next section for some comments about
avoiding clicks and pops.

Some older drives have trouble starting at the exact start of audio tracks.
The extraction starts a few blocks forward of where it should, and ends a
few blocks later, so the track may not sound quite right and the extraction
program will report errors at the end of the last track.  See section (4-19).

The Lite-On LTN483S 48x CD-ROM drive has a fairly unique bit of brain
damage: it doesn't extract the last two seconds of a track correctly.
This is only apparent on audio CDs with a "cold stop", where the music
plays right up to the very end of the track.  If the track has two seconds
of silence at the end, there are no apparent problems.  Apparently
there is a firmware fix for this (the PD03 update), available from
http://support.euro.dell.com/de/de/filelib/download/index.asp?fileid=R20664
or http://support.dell.com/us/en/filelib/download/index.asp?fileid=R20664.

One minor note: the data on audio CDs is stored in "Motorola" big-endian
format, with the high byte of each 16-bit word first.  AIFF files also use
this format, but WAV files use "Intel" little-endian format.  Make sure
your software deals with the endian-flipping correctly.  Byte-swapped CD
audio sounds like "static".


Subject: [3-2-1] How do I remove the voice from a CD track, leaving just music?
(2003/11/29)

A common reason for wanting to do this is to have a disc that can be sung
along with, either for personal practice or for karaoke.  There isn't a
perfect method for doing this, but it's possible to get close with some CDs.

Music is generally recorded in independent tracks and then mixed into a
balanced whole.  The recording studio can create masters with or without
the vocals, which is where a "clean" karaoke source comes from.  The music
is usually recorded in stereo, and the vocals in mono (the singer has one
microphone).  The mixed result has slightly different signals on the left
and right channels for the music, but the same signal on both channels
for the vocals.  By removing all signal components that are equal on the
left and right channels, the vocals can be removed with relatively little
distortion of the music.  This is called "center channel elimination".

This doesn't always work out in practice.  If the track in question doesn't
keep the vocals "centered", all bets are off.  Many musicians apply effects
to the vocals to achieve a certain effect -- often, to make it sound like
they can sing better than they actually can.  These effects aren't usually
"centered", so part of the voice remains.

Center channel elimination can be done with a good sound editor, such as
Cool Edit 2000 or GoldWave.  The procedure to follow with Cool Edit is:

 - Extract the CD track into a WAV file.
 - Load the WAV file into Cool Edit.
 - Create a new window with no WAV file in it (File->New...).  Set the
   settings at 44.1KHz 16-bit *mono*.
 - Switch back to the original WAV file (with the "Window" menu).
 - Select the entire left channel in the original WAV file.  If you move
   the mouse to the top of the WAV display area, the mouse cursor gets a
   little 'L' next to it.  Pick a spot near the middle of the screen,
   left click, and drag all the way to the left edge.  Then move the cursor 
   back to the middle, right click, and drag all the way to the right edge.
   You should now have the entire left channel selected.
 - Select "copy".  Switch to the new WAV file, and select "paste".  Switch
   back to the original.
 - Move the mouse cursor near the bottom of the WAV graphic until the mouse
   pointer gets an 'R' next to it, and select the entire right channel the
   way you did the left.
 - Select "copy".  Switch to the new WAV file.  From the Edit menu, select
   "Mix paste...".
 - Select "Overlap (Mix)", volume of 100, and check the "Invert" checkbox.
   Click "OK".

GoldWave now includes a "Reduce Vocals" feature.  Simply extract the CD
track into a WAV file and select it from the Effects menu.

The result is a single track with the center channel removed.  Hit the
"play" button and see what it sounds like.

The converse operation -- extracting the vocals and deleting the music --
is not currently possible.  (If you express the situation mathematically,
the problem is one of three variables in two equations.  The software
needs a new feature that subtracts tracks and retains the other part.)


Subject: [3-2-2] How do I encode a CD track to MP3?
(2003/08/11)

Extract the audio from the CD, then encode it into an MP3 at a quality level
you like.  Some programs combine the "rip" and "encode" into one easy step.

Higher quality settings result in larger MP3 files.  Most people can't
tell the difference between an MP3 at 160Kbps and the original.

Some tutorial sites:
 - http://www.chrismyden.com/DAE/
 - http://www.cdpage.com/Compact_Disc_Consulting/Tutorial/mp3.html
 - http://www.mp3-faq.org/
 - http://help.mp3.com/help/article/wav_to_mp3.html

Some software sites (mostly for Windows):
 - Apple iTunes, http://www.apple.com/
 - MusicMatch Jukebox, http://www.musicmatch.com/
 - Xing AudioCatalyst, http://www.xingtech.com/
 - Real Jukebox, http://www.real.com/jukebox/
 - LAME, http://lame.sourceforge.net/
 - BladeEnc, http://bladeenc.mp3.no/

There are others.  The quality of the result depends greatly on the quality
of the encoder.  There is no "best" encoder, but the Fraunhofer codec
and the LAME and Blade encoders usually do well.  ("Codec" is short for
"encoder/decoder".)

If your MP3s have a static sound in them, you might be getting a bad "rip".
The all-in-one rip+encode programs don't always do a great job extracting
audio from the CD.  You may want to "rip" the audio manually with EAC
(6-2-12) and then encode the WAV files.  (Recent versions of EAC can
extract to MP3 if you have a codec installed.)


Subject: [3-3] How do I get rid of hisses and clicks on audio CDs?
(2002/02/25)

If you're interested in removing noise from audio captured from an analog
source, such as a record player or analog cassette tape, skip to section
(3-12-3).  This section is about unexpected noise in audio from digital
sources, such as tracks extracted from a CD.  (Start with section (3-2)
if you are new to "ripping" or copying audio tracks.)

The single most important rule of noise removal is to figure out where the
noise came from.  Play the .WAV files off of your hard drive (if you're
doing direct CD-to-CD copies, extract a track and listen to it).  If you
hear noise in the .WAV on your hard drive, the digital audio extraction
isn't working very well.  You either need to extract more slowly, extract
from a different device, find a program that works better, or maybe just
clean the dust and grime off the source CD.  For more information, including
a URL for recommended software and the CD-DA FAQ, see section (3-2).

Always start by inspecting the CD.  If you borrowed it from a library,
don't expect it to be in pristine condition.  With enough abuse, even CDs
will sound bad, and audio *extraction* is more susceptible to such errors
than audio *playback*.  (This is what makes copy-protected CDs possible;
see section (2-4-2).)

If the problem sounds like repeated or skipped samples, rather than clicks
or hissing, the problem is probably jitter during extraction.  See section
(2-15) for an overview, and then give EAC a try (section (6-2-12)).

A nifty trick for comparing two .WAV files is to use the "Mix Paste"
feature of an audio editor like Cool Edit.  Extract a track twice, then
use Mix Paste to copy an inverted version of one file on top of the other.
The two sound files will cancel each other out wherever they are identical,
and have little spikes where they are different.  This can be useful
for seeing if the problems are only on one channel or are happening at
regular intervals.  You need to make sure though that both files start at
the same place though.  If your CD-ROM drive doesn't always extract from
the start of the block, you will need to adjust the files so they line up.

Useful things to do with this include comparing two extractions from the
same drive, extractions from different drives, or extractions from the CD-R
you just wrote to the original .WAV file you used to write it.

If you just want to see if the files are the same, use the DOS File Compare
command, with the "binary" switch set: FC /B FILE1.WAV FILE2.WAV.

Some CD-ROM drives may put a click a few seconds into the first track being
extracted.  This appears to be related to the drive spinning up.  Try
starting the extraction, cancelling, and then immediately restarting.

It is possible, though still somewhat unlikely, that you are trying to
extract from a copy-protected CD.  Section (2-4-2) discusses this in
some detail.

The rest of this section only applies if the extracted audio sounds fine on
disk, but has problems when played back from the CD-R.


If you're using track-at-once recording, you may get a short click or
silent "hiccup" at the start of each track.  Hiccups are unavoidable, but
you should be able to get rid of the click by using different software.

If you're using disc-at-once recording, and are still getting a short click
at the *start* of every track, then your recording software is probably
writing the sound file with the headers still on it.  You should either
use a smarter program, or remove the header manually (see the URL for
"StripWav", below).

If you are getting clicks in the middle of a track, they are either being
added when pulling the data off the disc or when writing it.  If the .WAV
(AIFF on the Mac) file plays without clicks, then your CD recorder may be
failing somehow during the write process.  Some people who got "static"
in audio recorded on an HP 4020i found that reducing the DMA transfer
rate to 2MB/sec helped.

One user was told by Yamaha tech support that crackling (similar to a dirty
vinyl LP) was a symptom of laser misalignment.  If you've been writing audio
CDs for quite a while, but lately you've been getting "crackly" results from
tried-and-true media, this might be the culprit.  Since it requires returning
the unit for repair, you should exhaust all other possibilities first.
(Side note: it's not clear how a laser gets "misaligned".  They have to
adjust themselves constantly to stay in the spiral groove.  It might be
due to poor focus, but that should be causing all kinds of problems.)

If you are getting clicks at the end of a track, it's possible that the
software used to create the .WAV file put some information at the very end,
which is legal but not handled correctly by some CD-R software.  See
section (3-12-3) for tips on using Cool Edit to remove the data.  If you are
finding that tracks extracted from CDs don't have clicks but tracks that
you have recorded or edited do, chances are the data size isn't a multiple
of 2352 bytes, and the last block is being filled with junk.  This is
common on live recordings or when large tracks are cut into smaller ones.
Jeff Arnold's DAO will fill out the last block with zeros (digital silence)
if there is space left over, but most of the other programs will write
garbage that is audible as a short (less than 1/75th second) click.  The
fix is to split the track on 2352-byte block boundaries.

A program called "StripWav" will remove .WAV headers and footers that
may be interfering with some applications.  The program is available from
http://www.lightlink.com/tjweber/.


If you must use track-at-once, make sure you're writing it all in one
session.  PC-based CD players may be able to see tracks in later sessions,
but the CD player in your stereo system almost certainly can't.

A distantly related problem can arise if you use "shuffle play" to play
random tracks from a CD-R.  If the audio of track N begins immediately,
some CD players will slide from the end of track N-1 into the start of
track N, playing a short burst of track N before seeking elsewhere.  This
can be avoided by putting a gap at the start of such tracks (e.g. with
"INDEX 01 xx:yy:zz" in a DAO cue sheet).


Subject: [3-4] How do I copy game console discs (e.g. Playstation, Dreamcast)
(2002/05/10)

For PCs, CloneCD (6-1-49) or CDRWIN (6-1-7) should work as well as anything.
For Macs, Astarte's CD-Copy (6-2-8) used to be recommended but may no
longer be available.

Note that the software does NOT defeat the copy protection.  I'm told
that the "copy protection" on Playstation discs is in fact a region code
-- America, Europe, Japan -- encoded near the start of the disc.  The "MOD
chip", a device attached to the Playstation that defeats one aspect of the
copy protection, emulates the country code reading process.  It sends all
three region codes back, enabling the game console to play original discs
from other regions as well as copied discs.  Some people say the code is
written in a block with damaged ECC, some say it's in the barcode on the
hub, others have insisted that it's in the ATIP region of the lead-in.
Whatever the case, it doesn't get copied by a CD recorder, and claims of
hacked recorder firmware that can create MOD-chip-free duplicates are false.

Instructions for copying discs and vendors who sell MOD chips can be found
by searching the net.  If you don't have a PC, or if your drive doesn't
support disc-at-once recording, you will need to look for disc copying
instructions on the net.

Sega Dreamcast discs use a proprietary format, called GD-ROM, which can
hold 1GB of data.  This makes it impossible to make an exact copy, though
it is possible in many cases to copy "enough" stuff to make them work.
Persistent rumors claiming that CeQuadrat's PacketCD can copy the discs
are false.  GD-R (Gigabyte Disc Recordable) media has two regions, a
"single-density" area near the hub and a "high-density" area farther out.
A visual inspection of GD-R media suggests that the single-density area
starts at about 22mm from the disc's center (same as a CD-R) and goes
to 29mm.  From 29mm to 31mm is a "no-mans" land that isn't recordable,
and the high-density area goes from 31mm to 58mm.  An image of one is
available on http://www.fadden.com/cdrpics/.

Incidentally, posting requests or advertisements for pirated software on
one of the non-warez Usenet groups is generally regarded as a mark of
extreme stupidity.  Whatever your opinion of software piracy, it is against
the law in much of the world.


Subject: [3-5] How do I get long filenames onto a disc?
(2002/05/19)

There are several different ways, most of which only work with some
operating systems.  The next few sections discuss the various methods.
See http://www.roxio.com/en/support/cdr/filesystems.html for a compatibility
chart.

It's important to remember that the most common CD filesystem (ISO-9660
Level 1) only supports eight-character filenames with a three-character
extension.  Longer filenames are added either as an extension to ISO-9660
(Joliet, Rock Ridge) or a replacement (UDF, HFS).  These are discussed
in the sections below.

Getting mixed-case filenames onto a disc is a similar problem.  Burning an
ISO-9660 disc with lower-case filenames isn't recommended, because some
systems aren't able to access the files even though they appear in
directory listings.

"mkhybrid" and recent versions of "mkisofs" (1.12b1 or later), described in
sections (6-1-32) and (6-1-10), respectively, are able to create CDs that
have both Joliet and Rock Ridge extensions.  "mkhybrid" can create discs
with Joliet, Rock Ridge, and Mac HFS on the same disc, sharing the same
file data.


Subject: [3-5-1] ISO-9660
(2000/05/12)

Level 1 ISO-9660 defines names to be the familiar 8+3 convention that
MS-DOS users have suffered through for many years: eight characters for the
name, a period ("full stop" for those of you in the U.K.), followed by
three characters for the file type, all in upper case.  The only allowed
characters are A-Z, 0-9, '.', and '_'.  There's also a file version number,
separated from the name by a semicolon, but it's usually ignored.

Files must occupy a contiguous range of sectors.  This allows a file to be
specified with a start block and a count.  (Most disk-based filesystems
require index blocks that list all the blocks used by a file.)  The maximum
directory depth is 8.

Level 2 ISO-9660 allows far more flexibility in filenames, but isn't usable
on some systems, notably MS-DOS.

Level 3 ISO-9660 allows non-contiguous files, useful if the file was
written in multiple packets with packet-writing software.  Also unavailable
under MS-DOS.  For the Mac, you can add support by installing Joliet
Volume Access (http://www.tempel.org/joliet/).

Some of the CD creation programs will let you select how closely you want
the CD to conform to the ISO-9660 standard.  For example, Easy-CD Pro 95
can restrict filenames to be ISO-9660 compliant, or allow the full set
of valid MS-DOS filenames.  (Most systems can handle MS-DOS filenames.)

Incidentally, the ISO-9660 spec requires that all files be displayed in
alphabetical order, with directories first, no matter how they are recorded
on the CD-ROM.  You can't arrange files on the disc, because the ISO-9660
reader (e.g. MSCDEX) sorts them before displaying them.


Subject: [3-5-2] Rock Ridge
(1998/04/06)

The Rock Ridge extensions to ISO-9660 define a way for UNIX-isms like long
mixed-case filenames and symbolic links to be supported.

Because it's still an ISO-9660 filesystem, the files can still be read by
machines that don't support Rock Ridge; they just won't see the long forms
of the names.

Rock Ridge is supported by UNIX systems.  DOS, Windows, and the Mac
don't currently support it.

Copies of the Rock Ridge standard and System Use Sharing Protocol (SUSP)
can be found at ftp://ftp.ymi.com/pub/rockridge/.  Pay a visit to
http://makecd.core.de/Rock_Ridge_Amiga_Specific for a description of
Amiga-specific extensions.


Subject: [3-5-3] HFS
(2002/02/25)

HFS is the Hierarchical File System, used by the Macintosh.  This is often
used instead of the ISO-9660 filesystem on Mac CD-ROMs, making the disc
unusable on systems that don't support HFS.

At present, the systems that can natively read HFS CD-ROMS are Macs, Amigas
(with AmiCDROM, available from ftp://ftp.cdrom.com/pub/aminet/disk/cdrom/),
PCs running Linux or OS/2 (with appropriate patches), the Apple IIgs,
and SGI machines running Irix (they appear as AppleDouble format).

Windows machines can read HFS disks with the appropriate
software.  One example is "Conversions Plus" from Data Viz,
http://www.dataviz.com/products/conversionsplus/.  Another is MacDisk,
from http://www.macdisk.com/prospen.php3.

Some authoring packages for the Mac and Windows allow the creation of
"hybrid" CDs that have both an ISO-9660 filesystem and an HFS filesystem.
Such discs can be used on non-Mac systems, but still have all the file
attributes (creator type, resource fork) that Mac OS likes.

Apple has defined some ISO-9660 extensions that allow Macintosh files to
exist with file and creator types on ISO-9660 CD-ROMs.  A description of
the extensions is available as tech note FL 36 from:
http://developer.apple.com/technotes/fl/fl_36.html


Subject: [3-5-4] Joliet
(2002/06/24)

Microsoft, being Microsoft, created their own standard called "Joliet".
This is currently supported by Win95 and WinNT.  It's useful when doing
backups from Win95 onto a CD-R, because the disc is still readable as
ISO-9660 but shows the long filenames under Win95.  The limit on Joliet
filenames is 64 characters.  (Some software reportedly allows up to 110.)

The spec can be found at
http://bmrc.berkeley.edu/people/chaffee/jolspec.html.

Recent versions of Linux (kernel >= 2.0.34 and 2.1.60) have Joliet
support.  Older versions can be patched; for details, see
http://www-plateau.cs.berkeley.edu/people/chaffee/joliet.html.

To patch Joliet support into OS/2, visit:
http://service.software.ibm.com/os2ddpak/html/miscellb/os_2warp/updatedc/index.htm

For the Macintosh, use Joliet Volume Access (http://www.tempel.org/joliet/).

Some old Creative CD-ROM drivers have trouble with CD-ROMs that have Joliet
filenames.  You may need an updated copy of sbided95.exe.  It used to be
available from http://www.ctlsg.creaf.com/, but that site no longer exists.


Subject: [3-5-5] Romeo
(2001/11/05)

Adaptec's Easy-CD Pro software allowed creation of discs in "Romeo" format.
Filenames may be up to 128 characters long, which is very useful for certain
types of files.  Sadly, this format never really caught on.  NTI's CD-Maker
software (section (6-1-12)) supports Romeo.

One person reported having trouble reading Romeo-format discs in Win2K,
others have had no problems.


Subject: [3-5-6] ISO/IEC 13346 and ISO/IEC 13490
(2003/10/14)

These standards were developed to replace ISO-9660.  They evolved into
what is now known as the UDF filesystem format (see section (6-3-1)).

Some older information is at http://www.standards.com/index.html#Standards.


Subject: [3-6] How do I use a CD-i disc on a PC?
(2000/10/24)

Short answer: you don't, unless you have a CD-i add-on board.  Even if you
have a CD reader compatible with the CD-i (Green Book) standard, there are
still a number of obstacles in your way.  The filesystem used isn't
ISO-9660, and CD-i players are based around a 680x0 CPU and have special
hardware for video and audio.

Longer answer: it depends on what kind of disc it is, and what you mean
by "use".

PhotoCD and VideoCD discs are CD-ROM/XA "Bridge Format" discs that play on
CD-i players as well as dedicated players and computers.  These use the
ISO-9660 file system, and can be read with commonly available PhotoCD
software and MPEG-1 players.

DigitalVideo discs from Philips manufactured before June, 1994 are in CD-i
format, not VideoCD format.  If your CD-ROM drive supports raw 2352-byte
sector reads, it's possible to pull tracks off of a Green Book format disc,
and extract audio or MPEG video data.  You can get a CD-i filesystem
for Windows from http://www.icdia.org/articles/filesystem.html.

VCD PowerPlayer from CyberLink (http://www.cyberlink.com.tw/) can play
CD-i movies directly off of a Green Book disc.

In-depth information is available from http://www.icdia.org/.


Subject: [3-7] How can I extract disc and track titles from an audio CD?
(1998/09/01)

Typical Red Book audio CDs don't have this information.  Software audio CD
players like those provided by Adaptec or Microsoft require you to type in
the information, which is then stored in a database on your hard drive.
The discs are identified by computing a signature based on track offsets
and other fields.  http://www.cddb.com/ acts as an Internet database of
CD info.

Some newer formats, like CD Extra, allow or even require such information
to be included on the CD.  See Sony's pages at http://www.cdextra.com/.

Some recent CD players are advertised as "CD-Text Ready".  These use the
CD-Text data embedded in the P-W subcode channels to display disc and track
title data.  See section (3-28) for more about CD-Text.


Subject: [3-8] How do I write more than 80 minutes of audio or 700MB of data?
(2004/03/04)

CD-R's have a pre-formed spiral track, and the sector addresses are
hard-coded into CD-R media, so there's no flexibility.  Every disc holds a
predetermined amount of data.

Most discs rated at 74 or 80 minutes hold slightly more than that.
How much more depends on the brand of media, batch of media, and perhaps
even on the recorder used (see section (7-6) for more details on how much
a CD-R can hold).  In some situations you can exceed the stated capacity
of the disc; see section (3-8-3) below.

Since CDs are written in a spiral, the amount of data you can get on
a disc is affected by how tightly spaced the "groove" is.  A standard
Red Book audio CD or Yellow Book CD-ROM is designed to allow at most 74
minutes of data.  By using a tighter track pitch on the spiral "groove"
on the glass master, manufacturers can get more data onto the disc.
In theory this could make it harder for some CD readers to use the discs.
See section (3-8-1) for notes on 80-minute discs, and (3-8-2) for 90-
and 99-minute blanks.

The easiest way to get more data onto a disc is not to try.  For audio CDs,
you can leave off one or two tracks that you're not overly fond of.  For
data CDs you may be able to drop some images or sample data.  The most
common problem people encounter with data CDs is trying to copy them as a
collection of files rather than doing a bulk copy of the entire disc.  See
also section (3-24).

One user suggested using the "speed up" function of Sound Forge or Cool
Edit to increase the speed of extracted WAV files by 3%.  This supposedly
gives better results than resampling, and allows writing 77 minutes of
audio onto a 74-minute disc.

If you have a mono recording, you could double the length of a CD by
recording half the sound on the left track and half on the right.  The
sound would be recorded as two monaural files, and then merged into a
single stereo file with a sound editor like Cool Edit.  (With Cool Edit
96: load first mono file.  Use "Convert Sample Type" to convert to
Stereo.  Select the right track, and Delete Selection.  Use Mix Paste to
load the right track from the second file, or just fire up a second copy of
Cool Edit with the other track, and use Copy and Paste commands.)  The
person playing the CD back will need to use a "balance" knob to select the

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