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

Section 4 of 6 - Prev - Next
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Taking it line by line, this says:
 - The default AutoRun command will be "setup /i"
 - The icon for the CD will be icon #1 embedded in setup.exe

 - Four commands will be added to the right-click pop-up menu:
 'Configure...',
   which will run "setup /c"
 'Install...',
   which will run "setup /i" (same as auto-run in this case)
 'Read Me',
   which launches notepad.exe to display "help\readme.txt"
 'Help',
   which displays the file "help\helpfile.hlp" with the Win95 help facility

You can test the autorun features of a disc without recording one.  If you
SUBST a folder onto a drive letter, the autorun feature will scan the new
drive.  For example, from a DOS prompt, enter "SUBST J: \goodies\NewCD".
This technique is also useful for testing out a CD-ROM you're preparing.

If you'd rather not have to deal with all this, try one of the applications
listed in section (3-21-3).


Subject: [3-21-2] How do I launch a document (like a web page)?
(2002/10/15)

In the past it was recommended to use the "start" command, e.g. "open=start
index.htm".  However, "start.exe" doesn't exist in the Windows NT family
(NT4, 2000, XP).

You can launch documents with Windows Explorer on any version of Windows,
like this:

  [autorun]
  open=explorer.exe index.htm

However, it appears to ignore your browser settings.  So, even if you've
chosen to make Netscape or Opera your web browser, it will still open the
HTML file with Internet Explorer.

An alternative to "start", called "shellout", is available from the "files"
section on http://www.mrichter.com/.  This is a trivial launcher that
you copy onto a disc and use like this:

  [autorun]
  open=shellout index.htm

It appears to avoid the above problems, is only 20K, and is free.

For more information on autorun:

  http://www.microsoft.com/msj/defaulttop.asp?page=/msj/0499/win32/win320499top.htm

Instructions for making a VideoCD autoplay under Windows can be found at
http://navasgrp.home.att.net/tech/autoplay_vcd.htm.


Subject: [3-21-3] What autorun software is available?
(2002/10/15)

Some simple, configurable autorun applications (launchers and menus) are
available, most as shareware:

  http://cloanto.com/menubox/
  http://www.indigorose.com/
  http://www.pollensoftware.com/autorun/
  http://www.phdcc.com/shellrun/
  http://www.mediachance.com/
  http://www.pgd.dk/
  http://hyper-publish.com/
  http://www.trah.co.uk/starterfile/
  http://www.startertool.com/
  http://go.to/traction/
  http://www.timeless.co.zw/software.cfm


Subject: [3-22] How can I be sure the data was written correctly?
(2002/12/10)

The easiest way is to compare the original with the copy.  Some programs,
such as recent versions of Nero, will automatically compare the disc
contents with the original files.  You can also use something like CD-R
Verifier from http://www.cdrom-prod.com/cd-r_verifier.html or CDCchedk
from http://Fusion.zejn.si/ to check the contents of an entire CD-ROM easily.

Another way is to do a recursive file-by-file comparison.  Programs that
compute CRCs on files and then compare them (often used for virus-checking)
will work.

One way to do this is with use the UNIX "diff" utility, which is
available for Windows (along with many other similar utilities) from
http://www.reedkotler.com/.  If you had copied the contents of C:\MyData
onto a CD-R at E:\, you would use:

    diff -q -r C:\MyData E:

The "-q" flag tells it to report if the files differ, but not show what
the differences are, and the "-r" flag says to descend into directories
recursively.

There are many other options.  A utility called "treediff", available
from the Simtel archives (http://www.simtel.com/), may be helpful.
http://www.funduc.com/directory_toolkit.htm has a shareware program with
some relevant features.  http://www.araxis.com/ has an evaluation copy
of PMdiff, available for Windows and native OS/2.  You can get "FileSync"
from http://www.fileware.co.uk/.

You can also use Microsoft's WinDiff, which -- unlike some of the
programs mentioned earlier -- understands long filenames.  It can be
found on Microsoft's recent operating system discs, e.g. on Win98 it
lives in \tools\reskit\file\windiff.exe.  It used to be available for
download from ftp.microsoft.com, but they rearrange that site frequently,
so there's not much point in including a URL.

An alternative to windiff is xdiff, from http://www.wookie.demon.co.uk/xdiff/.

Rocksoft Pty has a product called Veracity (http://www.veracity.com/) that
can check the integrity of a directory tree.

Visit http://www.fuw.edu.pl/~jt/cdvfy/ for some shell scripts that will
compute MD5 checksums on a tree.  Under Windows, try Advanced CheckSum
Verifier from http://www.irnis.net/ for MD5 and CRC32, or md5summer
from http://www.md5summer.org/.

If you *really* want to verify your discs, try http://www.audiodev.com/.


Subject: [3-23] How do I create, copy, or play Audio Karaoke/CD+G discs?
(2003/10/14)

For playing Karaoke and CD+G:

 - Various - http://www.karaoke.com/downcdg.html
 - WinCDG - http://windowstracker.com/

For creating them:

 - PowerKaraoke - http://www.powerkaraoke.com/
 - CD+G Creator - section (6-1-52)
 - DART Karaoke Studio - http://www.dartpro.com/products/DARTKarStudioCDGV1.asp
 - Karaoke Builder - http://www.karaokebuilder.com/
 - Some fancy stuff - http://www.mtu.com/

For copying them (some software can do individual tracks):

 - CDRWIN - section (6-1-7)
 - CloneCD - section (6-1-49)

To copy a disc, your reader and writer should ideally support "RAW DAO-96"
mode.  The CD+G data is stored in the R-W subcode channels (section (2-6)),
which not all drives are able to read and/or write.

See http://magicland.com/karaoke/drives.htm for a list of CD-ROM drives
compatible with Karaoke CDs, and check the CloneCD page for a list of
recorders that support "raw" reads and writes.


Subject: [3-24] How do I copy a CD-ROM with 3GB of data on it?  A huge VideoCD?
(2002/12/20)

You don't.  The CD-ROM doesn't actually have that much data on it.  Some CD
publishers use a trick where they reference the same spot on the disc several
times with overlapping files.  If you try to do a file-by-file copy from
the disc onto your hard drive, you'll end up with several copies of the
same blocks, and more data than can fit on a CD-ROM.

VideoCDs often appear to have individual files that are 700MB or more.
In this case, they really *are* that big.  They're written in a special
format (CD-ROM/XA Mode-2 Form-2) that drops error correction in favor
of more space.  This works fine for video data, but is definitely not
recommended for ordinary data.

If you want to duplicate a CD-ROM, you should use a program meant for the
purpose (CloneCD, CDRWIN, etc).  Some software is more capable of dealing
with complex CDs than others, so if you have a particular kind of CD in
mind (such as VideoCD) you should check the capabilities of the software
before making a purchase.


Subject: [3-25] How do I get my CD-R pressed into a real CD?
(2000/04/11)

There are a large number of companies that will do modest production
runs of pressed CDs, but listing them is beyond the scope of this FAQ.

Do a web search on "CD duplication" and "CD replication", or check out
http://www.cd-webstore.com/BurningIssues.html (a licensed-access web
site from the www.cd-info.com folks).

Sometimes a disc submitted for duplication will be rejected due to E32
(uncorrectable) errors.  If you have a disc rejected, make sure you are using
disc-at-once recording mode -- the gaps left between tracks by track-at-once
mode are sometimes interpreted as errors.  If the problems persist, try
changing to a different kind of media, or even a different recorder.


Subject: [3-26] How do I make a CD without that two-second gap between tracks?
(2000/03/10)

Most CD recorders are capable of doing this, given the right software.  The
key is to use disc-at-once recording instead of track-at-once.

Some programs give you a great deal of control.  Golden Hawk's CDRWIN
(6-1-7) will let you specify the gap size for each track, down to zero, and
set the location of the track and index marks.  You can put each track in a
separate file or have the entire recording in a single file.  Other
programs, like ECDC (6-1-26), are easier to use but less flexible.

You will almost certainly need to use disc-at-once recording.  Most drives
insist on inserting a two-second gap between tracks when track-at-once
recording is used, and those that don't will at best leave an instant of
silence between tracks.  You can eliminate the gaps from a TAO recording by
putting the entire CD into one track, but then you lose the ability to seek
immediately to the start of a song.

Most PC and Mac software support both TAO and DAO recording modes.  It's
prudent to check the web pages before you buy.

If you want to break up a long recording into several WAV files (one per
track), it's important to split tracks on precise 2352-byte boundaries.
If you don't, you'll get tiny periods of silence or noise, lasting less
than 1/75th of a second, that may be clearly audible depending on the
context.  A handy Windows utility called "CD Wave" (section (6-2-16))
is good at splitting large WAV files into smaller ones, and can do so on
block boundaries.

If you want to mix WAV tracks together, take a look at Multiquence,
http://www.goldwave.com/multiquence/index.html.  A simpler merge utility
is "wavmerge", from http://www.mrichter.com/cdr/files/files.htm.


Subject: [3-27] How can I record RealAudio (.ra), MIDI, WMA, and MP3 on a CD?
(2001/01/22)

Most CD players can only handle uncompressed audio in "Red Book" format.
Some newer player, such as the AIWA CDC-MP3 and Philips Expanium, can play
MP3 files from a CD-ROM.  Such discs should be written in ISO-9660 with
8+3 filenames, and ought to use 128Kbps and "plain" stereo for broadest
compatibility.  The documentation for the I-Jam (http://www.ijamworld.com/)
recommends putting no more than 50 MP3 files in a directory.

If you don't have such a player, though, you need to write a standard
"Red Book" audio CD.  The first step is to convert from whatever format
the sound is in to WAV or AIFF.  In some cases (e.g. MP3), many of the
popular CD recording programs will do the conversion for you.  If not, you
will need to convert it to 44.1KHz 16-bit stereo PCM format.  Once it's
in WAV or (on the Mac) AIFF format, you can record it as you would audio
taken from other CDs.  Be sure to play it back once after you convert it
to make sure that it came out okay.

For a tutorial on converting CD-DA to MP3 and vice-versa, see
http://www.cdpage.com/Compact_Disc_Consulting/Tutorial/mp3.html.  The
"getting started" guide at http://help.mp3.com/help/ is worth reading, and
the newsgroup FAQ for alt.binaries.sounds.mp3.* at http://www.mp3-faq.org/
is also useful.  Making MP3s from CDs is discussed on
http://mmsound.about.com/compute/mmsound/library/weekly/aa032700a.htm.

WMA is Windows Media Audio, part of Microsoft's attempt to create an
architecture for "Digital Rights Management" protected media.  A WMA
player isn't supposed to let you hear any music you don't have the right
to play.  If you want to record it to CD, and the player won't let you
do the conversion to WAV, you can still use a general-purpose sound
recorder like Total Recorder to do the job.

There may or may not be a converter for the format you're interested in.
Here are some links to try:

MIDI
 - http://www.advicom.net/~diac/mr-home.html  (MIDI Renderer)
 - http://www.polyhedric.com/software/  (MIDInight Express)
 - http://home.att.net/~audiocompositor/  (Audio Compositor)
 - http://www.dartpro.com/  (DART CD-Recorder)

MPEG audio (a/k/a MP2 and MP3)
 - http://www.mpeg.org/~tristan/MPEG/mp3.html  (various)
 - http://www.winamp.com/  (Winamp)
 - http://www.mp3.com/  (various)
 - (Feurio, WinOnCD, Nero, and perhaps others will record from MP3 on the fly)

RealAudio
 - http://www.realaudio.com/  (Real Jukebox Plus)

General (sound driver that writes to disk -- works for anything you can play)
 - http://www.HighCriteria.com/  (Total Recorder)

You can't write MPEG, AC3, or other compressed audio formats to a CD-DA
disc and expect to play it back in your car stereo.  CD players only
understand uncompressed PCM audio.

See http://www.howstuffworks.com/mp3.htm for an intro to MP3 technology.
The site at http://privatewww.essex.ac.uk/~djmrob/mp3decoders/ has
comparisons of various MP3 players.

http://www.sonicspot.com/multimediaconverters.html has a collection of
converters for different formats.

If you *really* want to be able to play MP3-compressed songs while driving
down the freeway, check out http://utter.chaos.org.uk/~altman/mp3mobile/
(or the commercial counterpart at http://www.empeg.com/).


Subject: [3-28] How do I add CD-Text information?
(2002/10/15)

CD-Text is a standard that allows disc and track information to be embedded
on an audio CD.  The data can be read by some CD players, providing a way
to have disc information available without having to enter it manually or
look it up in a database.

Adding CD-Text to the discs you record requires a compatible recorder and
capable software.  Support was scarce in mid-1999, but is more common now.

The currently available software supports writing of album title, artist
names, and track titles, and can copy discs with CD-Text data already on
them.  Storing lyrics within the tracks is possible but not widely
supported.

Not all CD players and CD-ROM drives can read CD-Text.  If this feature is
important to you, check the specifications before you buy.  Some programs,
notably Windows Media Player, claim to read CD-Text but will actually use
an Internet database instead.

Some MD recorders have a feature that lets you copy the CD-Text info
from audio CDs (e.g. "Joint Text"), but it appears that some CDs prohibit
the copying.  The result is the message "Text Protected".

The site http://www.ncf.carleton.ca/~aa571/cdtext.htm has some additional
details.


Subject: [3-29] Can I distribute a web site on a CD-ROM?
(2003/07/08)

You need to include the content and a browser on the CD.  Some products that
might be helpful are:

  PHD Computer Consultants - Dynamic CD (run dynamic ASP sites from CD):
    http://www.dynamic-cd.com/

  Softword Technology - Browse and View:
    http://www.pc-shareware.com/browser.htm

  Faico - NavRoad
    http://www.offlinebrowser.com/ or http://www.faico.com/

  Verity - Publisher
    http://www.verity.com/

See http://www.phdcc.com/helpindex/cdroms.html for some suggestions on
putting web pages on CD-ROM.  See http://www.spy-cd.com/ for a Java-based
CD search engine.

See http://www.microsoftfrontpage.com/content/ARTICLES/fp_to_cdrom.html
for an article about creating HTML CDs using FrontPage 2002.

If it doesn't need to be in HTML format, the full Adobe Acrobat writer
can reportedly convert an entire web site into a PDF document.

Incidentally, if you burn the disc with plain ISO-9660, you don't have
to worry about the upper-case filenames conflicting with lower-case names
in URLs.  The filesystem code on Windows, Mac, and UNIX converts the names
to upper case before comparing them.  This may not hold for other formats,
e.g. Rock Ridge.


Subject: [3-30] How do I clean my CD recorder?
(2003/06/04)

In general, you shouldn't.  Generally speaking, the only reason you'd need
to clean a recorder or (for that matter) a CD-ROM drive is if you went and
stuck your finger on the lens.  Cleaning kits and well-intentioned Q-tips
are unnecessary and potentially dangerous.  If you push too hard on the
lens while cleaning and damage the mounting, it will no longer matter how
clean it is.

Some people report drives coming back to life after a careful cleaning,
so there may be some value in doing so.  If your drive has become
increasingly flaky over time, cleaning it may help.

[ Personal note: I've never had to clean a lens in *any* CD player,
including a flip-up top-loading boom box that I've had since mid-1990.
I can *see* the dust inside, and I can see the lens, but it has no problem
playing discs.  I can't imagine how a recorder that's only a year or two
old is going to collect enough dust to fail, unless you play a lot of
really crusty discs. ]

If you have an overwhelming desire to clear loose dust out of your recorder,
and can't or don't want to send it to a service center, use gentle(!)
bursts of compressed air (like that used to clean camera lenses).  The idea
is to knock any dust loose without knocking the lens free of its mounting.
A more vigorous approach is to use a Q-tip and 99% isopropyl alcohol
(a/k/a isopropanol or IPA), but this should only be used if the previous
approach fails.  If you can only find 70% "rubbing alcohol", try to find
99% methyl alcohol (a/k/a methyl-hydrate or methanol), which is widely
recommended for cleaning magnetic tape heads.  It can usually be found in
paint or automotive stores as shellac thinner or windshield antifreeze.

The Repair FAQ at http://www.repairfaq.org/ has a section about CD-ROM
drives that seems relevant.  Find the "Compact Disc Players and CDROM Drives"
section, and skip down to part 4.  One relevant quote, from section 4.3,
regarding "cleaning discs":

  "I generally don't consider CD lens cleaning discs to be of much value
  for preventive maintenance since they may just move the crud around.
  However, for pure non-greasy dust (no tobacco smoke and no cooking
  grease), they probably do not hurt and may do a good enough job to put
  off a proper cleaning for a while longer.  However, since there are
  absolutely no sorts of standards for these things, it is possible for a
  really poorly designed cleaning disc to damage the lens.  In addition,
  if it doesn't look like a CD to the optical pickup or disc-in sensor,
  the lens cleaning disc may not even spin.  So, the drawer closes, the
  drawer opens, and NOTHING has been accomplished!"


Subject: [3-31] Is it better to record at slower speeds?
(2003/01/13)

It depends on your recorder, media, and who you talk to.  For example,
some informal testing with the venerable Yamaha CDR-100 determined
that it worked best at 4x speed with media certified for 4x writes.
1x worked almost as well, but 2x would occasionally produce discs with
unrecoverable errors.

With audio CDs, the results are more subjective.  Some people have asserted
that you should always write at 1x, others have stated that 2x may actually
be better.  It depends on the recorder, media, player, and your ears.  Try
it both ways and listen.  See section (4-18) for some notes on how you can
write the same set of bits to two CDs and still have audible differences.

CD-R media is written by heating up tiny sections of the disc.  When the
disc spins faster, the laser has less time to shine on a particular spot,
so the laser has to be controlled differently.  Different formulations of
media may require a different "write strategy" at certain speeds, and each
recorder may adjust its write strategy differently to accommodate those
speeds.  This can potentially result in combinations of recorder and media
that work perfectly at one speed but fail miserably at another.

Put simply, there's more to writing at high speed than just spinning faster.
It's entirely possible that writing slowly to "high-speed" media will
produce significantly worse results than writing to it quickly.

There is no One True Answer to this question.  Do what works best for
what you have.  Some experimentation may be required.

See "The Speed of Sound: How Safe is High-Speed CD-Audio Recording?" at
http://www.emedialive.com/EM2000/starrett5.html, for a very thorough
analysis of audio disc quality at several different speeds.  With some
recorders and some media, it's actually better to write faster -- but in
none of the tests performed did the error rate get anywhere near danger
levels, regardless of speed.

See the graphs in the article "Glenn Meadows' CDR Tests" at
http://www.digido.com/ for an examination of BLER (BLock Error Rate) with
different recorders, different media, and different recording speeds.
A few of the graphs show the same recorder and same media at different
speeds, and in some cases the BLER increased at higher speeds, while in
others it decreased.

There is some cause to believe that recording at higher speeds can result
in increasing "jitter".  This doesn't cause any difference in BLER or in
the extracted audio, but is audible during playback.  See section (2-41).

See http://www.cd-info.com/CDIC/History/Commentary/Parker/stcroix.html for
commentary about "write strategy" selection and different media types.


Subject: [3-32] Where do I get drivers for my CD recorder?
(1998/04/06)

In general, you don't need them.  Software that burns CD-Rs has the
necessary drivers built in.

If you want to use certain older recorders as CD-ROM drives, you may need
drivers for them.  See section (5-8).


Subject: [3-33] Can I copy discs without breaking the law?
(2001/01/06)

This varies significantly from country to country.  Information for USA
and Canada follows.  Most nations have some form of copyright protection
that restricts duplication.


Subject: [3-33-1] ...in the United States of America?
(2001/01/06)

You are allowed to make an archival backup of software, but the same
doesn't necessarily hold true for music.  The Home Rights Recording Act
will allow you to duplicate music under certain circumstances.

A discussion of the topic, including details on past and pending
legislation, can be found on the Home Recording Rights Coalition web site
at http://www.hrrc.org/.  The text of the Home Rights Recording Act can
also be found here.

The Recording Industry Association of America, which represents the music
industry, has a web site at http://www.riaa.com/.

An article entitled, "Copying Music to CD: The Right, the Wrong, and the
Law" is at http://www.emediapro.com/EM1998/starrett2.html.

http://www.brouhaha.com/~eric/bad_laws/dat_tax.html has some relevant
information and pointers.

http://www.bmi.com/ and http://www.ascap.com/ have yet more perspectives
on legislation.


Subject: [3-33-2] ...in Canada?
(2003/09/16)

Rules for copying software resemble those in the USA.

The rules for music are more lenient.  Because of the media tax imposed
by the Canadian government (see section (7-13)), you are allowed to copy
any music for your own personal use.  This means that you can go over to
a friend's house and copy any number of discs you like, so long as they
are for your own use.  You are not allowed to make copies of music and
then give them to others.

See http://www.cb-cda.gc.ca/decisions/copying%2De.html, notably "Tariff
of levies to be collected by CPCC in 1999 and 2000 for the sale of blank
audio recording media in Canada" (PDF in both English and French).

http://techcentralstation.com/081803C.html points out that downloading MP3
files from P2P networks (e.g. the original Napster) is legal in Canada.
(The article actually claims that sharing is entirely legal, but by the
terms of the law downloading is legal and uploading is not.)


Subject: [3-34] Can CD-Rs recorded at 2x be read faster than 2x?
(1999/09/22)

Of course.

The only possible basis in fact for the, "if it was recorded at 2x, you
can't read it faster than 2x" rumors is that some drives have trouble
reading CD-R media.  Discs that are hard to read when spinning at 12x may
become easier to read when spinning at 4x.  It has also been noted that
some recorders will write more legible discs at certain speeds (e.g. the
Yamaha CDR-100, which works better at 1x or 4x than it does at 2x).  None
of this should lead anyone to conclude, however, that the write speed and
read speed are tied directly together.  The reader, writer, and media all
have a role in determining how quickly a CD-R can spin and be readable.

It's also the case that discs written at high speed (say 8x) can be read by
drives *slower* than 8x.  So if you're distributing discs to people with
old 4x CD-ROM drives, you don't have to worry about them not being able to
read at 8x.  Of course, if the CD-ROM is poorly constructed, or the writer
is producing marginal discs at high speeds, you might see evidence to the
contrary, but there is no technical barrier to reading discs recorded at
8x or 12x on a slower drive.


Subject: [3-35] How do I make my CD-ROM work on the Mac, WinNT, and UNIX?
(2002/08/01)

This is a tricky one because of issues with long filenames and file
attributes.  Mac CD-ROMs are typically burned with an HFS filesystem, not
ISO-9660, and WinNT uses a different scheme for long filenames (Joliet)
than UNIX does (Rock Ridge).  Some variants of UNIX will recognize the
Joliet names, but neither Windows nor the Mac understands Rock Ridge.  You
might be able to use an HFS CD-ROM on a platform other than the Mac, but if
you're distributing software, it's not wise to assume that your customers
will be able to do the same.

The easiest way to create a disc that will work on all platforms is to use
plain level 1 ISO-9660, with 8+3 filenames and no special file attributes.
If you need to include Mac applications as well as data -- or pretty much
anything with a resource fork -- this simple approach won't work.  Also,
some older versions of Mac OS and HP/UX might not work as expected unless
you record the disk without the usually-invisible version number (";1").

There is an Apple-defined extension to ISO-9660 that allows the Mac file
and creator types to be present on an ISO-9660 filesystem.  This allows most
of the features of the Mac filesystem on an otherwise plain ISO-9660 disc.
It's not clear how many of the software products in section (6-1) take
advantage of this, but "mkhybrid" (section (6-1-32)) and MacImage (section
(6-2-10)) seem to.  Section (3-5-3) has a URL to an Apple tech note with
implementation details.

A common way to construct a disc for the Mac and PC is as a "hybrid" disc
that has both an ISO-9660 filesystem and an HFS filesystem.  To save space,
the data itself is shared by both sections of the disc.  This is possible
because the ISO-9660 directory entries use an absolute block offset on the
disc, so they can point at data residing in the HFS filesystem.

There are various applications that will do HFS/ISO-9660 hybrids.
Roxio's Toast for the Mac and "mkhybrid" for the PC are two examples.
Search for "hybrid" in the list of software in section (6-1) for more
examples.

The issue of Joliet vs. Rock Ridge can also be solved, by including both
kinds of extensions on the same disc.  The "mkhybrid" program can include
Joliet, Rock Ridge, and HFS all on the same disc.  You can even have files
appear on one kind but not the other, and rename files on the fly, allowing
you to have a "readme.txt" with different contents for Mac, UNIX, and
Windows.


Subject: [3-36] How do I put "hidden tracks" and negative indices on audio CDs?
(2001/06/26)

With a little searching you can find an audio CD that will cause your CD
player to show a negative track time when one track finishes and the next
begins.  The negative sections are usually filled with silence, but some
rare discs will have material in them.  If you seek directly to the track,
you don't see (or hear) the negative-time section.

The trick here is also described in section (3-14).  You can specify the
start position of an audio track anywhere within the track.  The start
position is at time index 00:00 (in minutes and seconds, MM:SS), so the
music before the start point is usually displayed with negative time values.
When you seek directly to a track, the player jumps to time index 00:00, but
when you play through from a previous track you hear the entire track.

When using CDRWIN-style cue sheets, the actual start of the track is at
"index 00", and the place where the player seeks to is "index 01".  The The
distance between the indices is called the pre-gap.  The Red Book standard
requires that index 01 in track 01 be at least two seconds (150 sectors)
from the start of the CD.

You can specify additional index markers, but most CD players will simply
ignore them.  Some CD-ROM games have tried to use the index markers as a
form of copy protection, because they won't get copied automatically by
many programs.


If you want to create your own discs with "hidden tracks", you need a program
that gives you full control over where the index markers go (CDRWIN is one
such program).  Combine two (or more) tracks with an audio editor into a
single file.  Specify the file as a single track in the cue sheet, set
"index 00" to time zero, and set "index 01" to a point right after the
"hidden" song finishes.  There are other ways to approach this, but this
is probably the most straightforward.

It should be mentioned that the only truly "hidden" track is in track 1.
Most CD players will play the entire disc, from index 01 on track 1,
straight through to the end, so any tracks you try to "hide" in the
middle of the disc are simply difficult to seek to.  The only way to play
audio tucked into the pre-gap in track 1 on most players is to hold down
the rewind button.

For more information about unusual audio CDs, see "CD Oddities" at
http://www.turbine.com/wj/oddcd/.


Subject: [3-37] Do I need to worry about viruses?
(1998/09/11)

Absolutely.  Infected CD-ROMs are every bit as nasty as infected floppies,
if not worse: you can't disinfect the source media.  It is prudent to
scan your files before creating a CD-ROM for distribution, and it's not
a bad idea to scan the CD-ROM afterward (in case somebody has cleverly
infected your CD writing software).

The dangers of boot sector viruses on bootable CD-ROMs are probably low.
Because the boot sector is created directly by the recording software, and
can't be modified after it has been written, the opportunity for infection
is small.


Subject: [3-38] How do I cover up a bad audio track on a CD-R?
(1998/09/11)

You don't.  With a CD-ROM you could use multisession writes to hide
unwanted data, but you can't create multisession audio CDs.  (Well, you can
create them, but nothing outside of a CD-ROM drive will be able to play the
tracks outside the first session.)

On CD-RW media, it might be possible to overwrite an individual track.  You
would need software that supported this capability.  Erasing the disc and
starting over is probably easier.


Subject: [3-39] How do I duplicate this hard-to-copy game?
(2001/12/18)

Requests for information on how to copy recent games occasionally sprout
up on the newsgroups.  Generally the publisher has employed some form
of copy protection that prevents the disc from being duplicated easily.
If you try to play the game from the duplicate, the game will usually act
as if the CD-ROM weren't present and tell you to insert it.

Most publishers are well aware that there is no such thing as an
unbreakable copy protection scheme.  It is possible though to implement
a method effective enough to slow the tide.  If you don't believe that,
start counting posts the next time a popular game with decent protection
is released.  See section (2-4) for some technical details, and section
(3-42) for a discussion of why you can't write a general-purpose disc
copier that works for everything.

If you're looking for information, the most appropriate places to search
are "warez" newsgroups and web sites.  Searching the net for tips is a good
way to get started.  Be forewarned that any "cracks" you download may very
well also be viruses, and that if you give away or accept a copy of the
disc from someone else you are probably breaking the law.

Aiding and abeting the illegal distribution of copyrighted works is not part
of this document's charter.  There are plenty of newsgroups and web sites
devoted to the subject, so please don't waste bandwidth in "legitimate"
forums asking for cracks.  A search engine such as http://www.google.com/
will turn up many sites with such information.

Incidentally, the government of the USA and several other countries are

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