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starting to crack down on illegal trading of software and digital video.
See http://www.usdoj.gov/opa/pr/2001/December/01_crm_643.htm for a press
release on a December 11 2001 crackdown.
Subject: [3-40] Should I erase or format a disc? How?
(2001/03/18)
First and foremost: you do not need to format a disc unless you're using a
packet writing program like DirectCD. If you're running a program to create
a CD, chances are good that you don't need to format it. If you're using
"drive letter access", i.e. treating the CD-R or CD-RW like a big floppy
disk, then you do need to format it.
Simple rule of thumb: don't format it. Most software that needs a formatted
disc will format it for you as needed.
Formatting and erasing are different things. Formatting prepares a disc
for recording. On a CD-R it writes a few basic things, on CD-RW it may
write to most of the disc. The fixed-packet formatting that DirectCD does
for CD-RW discs takes about 50 minutes on a 2x-speed rewritable drive.
Erasing, which can only be done to CD-RW media, restores the disc to a
pristine state. If you want to erase a disc, use the software that came
with your CD-ReWritable drive. Somewhere in the army of applications and
mountain of menus is the command you're looking for.
The difference between "erase" and "quick erase" is that the former erases
the entire disc, while the latter just stomps on the Table of Contents
(TOC). It's like erasing the directory off of a floppy disk. The file
data is still there, but since there's nothing pointing to it, the disc
appears empty. (Some people have asked if it's possible to recover data
from a quick-erased disc. Acodisc can do this; see section (4-35).)
The difference between "format" and "fast format" (such as is offered on
the HP8100/Sony CRX100) is of a different nature. Both format the entire
disc, and both operate at the same speed, but the "fast" format allows you
to use the drive before formatting has completed. After a few minutes, you
are allowed to access the drive while the formatting process continues in
the background.
Incidentally, most conventional (pre-mastering) software will refuse to record
on a disc that has been formatted for packet writing. In some cases the
error message may be a confusing remark that insists the disc isn't writable.
Subject: [3-41] How do I equalize the volume for tracks from different sources?
(2003/08/01)
A common problem when creating an audio CD compiled from many different
sources is that the sound is at different volume levels. This can be
slight or, after you've cranked up the volume to hear the first track, very
much the opposite of slight.
There are actually two issues that determine how loud the music sounds.
The first is the signal amplitude. Put simply, if you open a WAV file,
this is how close to maximum the squiggly line gets. You can adjust the WAV
file so that the highest amplitude is at maximum with the "normalize peak"
function of a sound editor. Some programs, such as Roxio's Spin Doctor,
may even do this for you automatically.
The second major issue is the dynamic range compression. This differs
from data rate compression in that it doesn't make the WAV file smaller.
Instead, it can make the quiet parts louder and the loud parts quieter.
A CD-DA has a dynamic range of about 96dB. If a symphony is recorded with
a range of more than 110dB, it has to be compressed to fit on a CD-DA.
In practice, you don't want whispers to be inaudible and shouts to be
deafening, so the audio is often squeezed into an even narrower range.
Radio stations often compress their broadcasts "up" so that music can be
heard more clearly by listeners in cars or work environments.
(According to Ken Pohlmann's _Principles of Digital Audio_, 4th edition,
page 35, ideal 16-bit quantization of a sinusoidal waveform is 6.02n+1.76
decibels, or 98.08dB. Using "dithering" techniques, it's possible to
extend the effective resolution well beyond this, because of the way
the ear perceives sound. There is an *excellent* introductory article
at http://www.digido.com/ditheressay.html. Compression is more often
employed on pop music recordings, where louder is better, than something
like classical music, where accurate reproduction is desirable.)
To make a CD that sounds like it has equal volume across all tracks, you
need to have the average sound level uniform across all tracks and have the
peak volume be about the same on all tracks. One program that does
essentially this is Audiograbber v1.40 and later, available as shareware
from http://www.audiograbber.com-us.net/. (As of v1.41, you went into
"Normalize Settings" and hit the "Advanced" button.) The tool is a little
clumsy for serious audio mastering, but should do fine for preparing a
"mix" CD that you'll be listening to in your car.
Another tool is "WAV file leveller", at http://home.plompy.co.uk/.
Some programs approximate compression by letting you normalize against
average RMS power. In this case, you are using a value that more closely
matches the apparent loudness of the recording.
If you aren't dissuaded yet, http://www.digido.com/compression.html has
an excellent article on compression, intended primarily for the budding
recording artist but a good general reference nonetheless.
http://www.prorec.com/prorec/articles.nsf/files/8A133F52D0FD71AB86256C2E005DAF1C
has an excellent article entitled "Over the Limit" about the Louder is
Better phenomenon in professional recording. The author examines the
progress of the trend by analyzing clipping and power levels in five
different Rush CDs recorded from 1984 to 2002.
Sidebar: "dB" is the abbreviation for "decibel", a signal strength ratio
measured on a logarithmic scale. In a WAV editor like Cool Edit, which
can show the sound level in dB, the signal level doubles every time you
add 6dB, and the "loudness" doubles every 10dB. This is different from
signal power levels, which double every 3dB (what you see in a WAV editor
is analogous to voltage, not power). Detailed information is available
from the Acoustics FAQ at http://www.campanellaacoustics.com/faq.htm.
See also http://www.ews64.com/mcdecibels.html and
http://www.modrec.com/about/excerpt.php. There is a comparison table at
http://www.gcaudio.com/Archives/volatgeloudness.htm that breaks things
down nicely.
Subject: [3-42] How do I make a bit-for-bit copy of a disc?
(2002/12/09)
A commonly posed question from the newsgroups: "what software can do
bit-for-bit copies?" The expectation is software that can make an exact
copy of the original.
There isn't any. If it helps to have a (convenient albeit somewhat
inaccurate) mental image, picture a long string of bits arranged in a
spiral. There are bits at the start of the spiral that you can't copy (the
lead-in area), there are bits outside the spiral that you can usually copy
if you request them ("raw" MODE-1 CD-ROM ECC and sector goop), and there
are bits *under* the spiral that are blurry and hard to see (the subcode
data).
What's more, there are copy protection features, such as *physically* damaged
blocks, that a recorder isn't generally capable of writing. Other tricks,
such as out-of-specification track lengths, can't be duplicated by most
CD recorders because the firmware refuses to write them.
In no event can you guarantee an exact duplicate of the level 1 ECC (CIRC)
encoding. In practice this doesn't matter, since no CD-ROM drive provides
an interface for reading it directly.
Making a "bit-for-bit" copy of a disc would require reading the data at the
lowest possible level, something that no production CD-ROM drive is capable
of doing. Even if it were possible, there aren't any CD recorders that can
write that sort of data.
Because of these limitations, you have to read a sector of data as a sector
of data, not as a collection of frames scattered over half the circumference
of the disc. The best you can do currently is "raw DAO-96" (section (3-51)),
which reads the subcode data along with the the sector data.
Bear in mind that CD-ROM drives and CD recorders were designed for people
who want to read and write data, not decipher arcane standards documents
and perform their own error correction. Creating exact one-off copies was
not a major consideration of the original design.
In general, however, you don't *need* a "bit-perfect" duplicate of the
original. If what you're copying is a simple MODE-1 CD-ROM, you can make
an "identical" copy by reading the sectors off the original and writing
them to a duplicate. For most situations this is good enough: you have
copied the bits that matter.
On the other hand, if it's a copy-protected CD-ROM with index markers in
strange places, you have to use software and hardware that can see the
"blurry bits" reliably and copy them.
See also sections (2-43), (3-1-1), (3-18), (3-39), and (6-1-49).
Subject: [3-43] How do I put punctuation or lower case in CD-ROM volume labels?
(1999/06/05)
The name of a CD-ROM is determined by the CD-ROM volume label. This
determines how the disc shows up on the Mac or Windows.
The ISO-9660 standard limits the characters in the volume name to the same
set of characters allowed in a filename, namely A-Z, 0-9, '.', and '_'.
Some programs enforce strict adherence to the standard, while others are
more relaxed.
For example, if you wanted to create a disc with Nero that had a hyphen in
the volume name, you would go into the "file options" and change the
Character Set to "ASCII". Nero will then allow a broader range of
characters. Other programs may or may not have similar features.
Remember that standards are guidelines, not laws enforced by threat of
punishment. You are welcome to create discs that deviate from the standard
in any way you choose. The only price you will pay is that, if you stray
too far from the standard, your disc may not be readable by everyone. For
the specific case of a volume label, deviations are pretty harmless.
Subject: [3-44] How do I extract audio tracks from an "enhanced" CD on the Mac?
(2001/10/02)
Applications like "Toast" insist on showing the data track only. You can
play the audio tracks, but you can't seem to extract them.
SoundJam MP from http://www.soundjam.com/ is reported to do the trick.
The CD-ROM toolkit from FWB (http://www.fwb.com/) might also be of use.
Subject: [3-45] How do I disable DirectCD for Windows?
(2001/01/06)
There are two basic approaches: (1) run the uninstall program, or (2) make
changes to several entries in the Windows registry.
You CANNOT disable it by killing a task.
You CANNOT disable it by un-checking it in msconfig.
You CANNOT disable it by removing it from the system StartUp list.
All these really do is stop the DirectCD control interface from running.
The icon is gone from the system tray, but DirectCD itself is still active,
which you can verify by inserting an unfinalized packet-written disc. If
DirectCD were actually disabled, the disc would be unreadable.
Writing data to such a disc without the user interface component active
can lead to data corruption, because some of the safeguards are no longer
in place. It's like you've taken the steering wheel off the car while
it's still rolling.
If you do choose to use one of the "easy" methods, you will probably be okay
so long as you don't try to write to a disc with packet writing.
DirectCD puts some drivers in C:\Windows\System\Iosubsys\. The set appears
to be CDUDFRW.VXD, CDUDF.VXD, CDRPWD.VXD, and CDR4VSD.VXD. If you are
having trouble un-installing DirectCD, check for the presence of these
files, and rename the extension to ".VX_" if found.
NOTE: the DirectCD icon in the system tray is different from and independent
of the "Create CD" icon that Easy CD Creator 4 adds to the system tray. You
can get rid of that by right-clicking on it and telling it not to load.
Subject: [3-46] How do I specify the order of files (e.g. sorting) on ISO-9660?
(2004/02/16)
Generally speaking, you don't. The ISO-9660 specification requires that the
files appear in sorted order. Modern operating systems will sort the files
for you anyway, so changing the file order won't usually do much for you.
Packet-written (UDF) discs behave differently.
One situation where sorting does matter is when creating an "MP3 CD", i.e.
a CD-ROM filled with MP3 files that will be played by a CD or DVD player.
Getting the songs in the order you want is usually accomplished by
prepending digits to the front of the name, e.g. "001" for the first song,
"002" for the next, and so on.
It is possible, if you don't mind creating discs that violate the standard,
to specify a sorting order without modifying the file name. MP3BR Imager,
from http://www.mp3br.com/, can do this for you. Just make sure you test the
discs for compatibility with your equipment before you get too carried away.
Subject: [3-47] How do I put a password on a CD-ROM?
(2000/03/14)
Encrypt the data on it. See section (3-19) for options.
Subject: [3-48] Can I record an audio CD a few tracks at a time?
(2000/04/11)
That depends on what you're trying to accomplish. There are two issues
that complicate matters:
(1) Most audio CD players only play tracks from the first session on
the disc. (Most CD-ROM drives will play all sessions.)
(2) Most audio CD players only play tracks from a closed session.
(In general, only a CD recorder can play from an open session.)
Suppose you record three tracks onto an audio CD, using track-at-once
recording. If you don't close the session, you can add more tracks, but
you can't play the disc. If you close the session, you can play the disc,
but you can't add more tracks.
Some people have CD players that will play songs from every session. If
you do, and compatibility with other players isn't important, you can
write each group of tracks into its own session. The down side of this
approach is that there is an appreciable amount of overhead when opening
a new session (23MB for the first and 14MB for each additional one).
If your hard drive has enough space, you can just keep the WAV files on
the drive, and burn the disc all at once. If it doesn't, you can write the
tracks to a CD-R or CD-RW disc as WAV files on CD-ROM, and record from there.
Write a new CD-R or CD-RW every time you get more tracks. (The advantage
to using CD-ROM is that additional error correction is used.)
Subject: [3-49] How do I copy DVDs onto CD-R?
(2002/11/15)
It isn't possible to take the contents of a DVD-Video or DVD-ROM and
record the whole thing onto a CD-R, unless the DVD is nearly empty.
The capacity of DVD discs is considerably greater. Generally speaking,
you can't play DVD content from a CD-R disc anyway, because the DVD drive
needs to read encryption keys from outside the filesystem area.
You could, of course, capture the video from a DVD-Video disc with a video
capture board, re-encode it with MPEG-1, and write that as a VideoCD.
The quality would be VHS-grade though. (You can get better results
with MP3 audio and MPEG-4 video, but the process is a little convoluted.
See http://www.digital-digest.com/dvd/support/dvd2mpeg4.html.) The
next section talks about some ads you might have seen for products that
do this.
You may have heard of DivX (sometimes "DivX ;-)"). Originally the name
for a limited-playback DVD system, it now usually refers to MPEG-4 encoding
of DVD video. See http://www.divx-digest.com/help.html for more details.
If you're only interested in the audio portion of a DVD-Video, you can
extract the AC3 audio directly from the .VOB file, using some freely
available utilities (notably "ac3dec" and the elusive "DeCSS"). You will
need to convert the audio from 48KHz to 44.1KHz. You can also capture
it under Windows with Total Recorder (6-2-19).
The story is the same with DVD-ROM: you can probably copy it to a CD-R if
it will fit. If the contents only took up about 650MB, though, it probably
wouldn't have been shipped on a DVD-ROM.
Subject: [3-49-1] I heard about software that copies DVDs with a CD recorder!
(2002/12/21)
I'm guessing you've also heard of ways to get rich by sending money
to other people, legal ways to get your bad credit history erased, and
drug-free side-effect-free low-cost super cures made from all natural
ingredients on distant tropical islands.
They're all nonsense. I can't help you if you believe in the above, but I
can speak to copying DVDs with a CD recorder. Here's a piece from a message
that was spammed at me (spelling and grammar errors left uncorrected):
COPY ANY DVD MOVIE
With our revolutionary software you can copy virtually any DVD Movie
using your existing equiptment! Conventional DVD copying
equiptment can cost thousands of $$$
Our revolutionary software cost less than the price of 2 DVD Movies!
If you go to the web site, it goes on to say:
Learn How To Burn DVD's onto Regular CD-R Discs and watch your new
movies on Any DVD Player, not just the computer DVD.
[...]
No DVD Drive Required!!!
Another, possibly unrelated, site says:
With detailed, easy to follow, step-by-step instructions, you can
BURN your own DVD Video using nothing more than our software and
your CD-R.
[...]
o No DVD Burner Required
o Superior Reproduction Quality
It has a link for their "frequently asked questions" document, but you have
to give them your e-mail address to get it. Any company that refuses to
give you information until you submit to their spam list is best avoided.
Let's start with the facts:
(1) You can't read a DVD in a CD-ROM drive. DVD requires a laser at
a different wavelength; the disc has a different physical format;
the disc has a different logical format. A firmware update is
not going to make this work, so don't expect that installing new
software is going to help.
(2) You can't put a full DVD on a CD-R disc. DVD movies are typically
around 8GB, which is roughly 11x as much as you can put on a CD-R.
(3) Many DVD players can't read CD-R discs. This is because of the
different laser wavelength. DVD player manufacturers have found
several ways around this, but many players just can't handle CD-R.
(4) You can't easily duplicate the blocks with the security keys. They
live outside the filesystem area. The only way to get the MPEG
video off in a playable format is to create a copy with the CSS
encryption removed. This requires either stripping the encryption
with software (DeCSS) or hacking the device driver to get the video
after the hardware has decrypted it. Both methods are, as of the
end of 2002, the subject of lawsuits in the USA because of DMCA law,
which makes such things illegal to write, sell, or even use.
Products like "DVD Wizard" and "DVD-Copy 2.1" cannot possibly do all
that they claim. The best they can do is transcode the video into a
lesser format. This requires ripping the MPEG-2 video off the DVD using a
DVD-ROM drive, stripping the encryption, re-encoding the video in MPEG-1,
and writing it to CD-R as a VideoCD. You will be going from 720x480
video recorded at up to 10.08Mbits/sec down to 352x200 video recorded at
1.5Mbits/sec. Instead of Dolby 5.1 you will have low-bit-rate stereo.
On an 80 minute disc, you can store about 80 minutes of MPEG-1 video,
so nearly all movies will require two or more discs.
This software will let you create a movie that could be played back in
computers or *some* DVD players -- not all DVD players support CD-R media,
and not all will play VideoCD -- but at roughly VHS quality, and without
any of the features that make DVDs special. Most notably, you will lose
all of the menus, audio options, and special features. You will not be
burning "DVD Video", and in some parts of the world (most notably the USA)
you will be breaking the law even if the copy is for personal use.
Software that does this sort of thing can be found, for free, on various
sites on the Internet. (Because of the legal issues, it isn't always
available in one place for long.) If you really want low-quality MPEG
editions, save your money and search the web for DVD copiers or converters,
and download the software for free instead of giving money to spammers.
(The previous section has a couple of links that might be useful.)
Subject: [3-50] How do I copy Mac, UNIX, or "hybrid" CD-ROMs from Windows?
(2001/03/03)
A program that copies the entire disc as an image should work. Don't
try to copy it as a collection of files.
You can create a hybrid HFS (Mac), Rock Ridge (UNIX), and Joliet (Windows)
CD-ROM with "mkhybrid" in section (6-1-32). The output of the program is
a simple ISO-9660 image file. It stands to reason that you should be
able to copy such discs as easily as you can create them.
The same applies to copying arbitrary discs from the Mac, or any other
platform -- just copy it as a disc, and you should be fine.
If you're trying to copy a game, and it doesn't work, see (3-39).
Subject: [3-51] How do I copy something in "RAW" mode? What's DAO-96?
(2002/12/09)
A sector on an audio CD holds 2352 bytes, enough for 1/75 of a second
of stereo sound. A sector on a MODE-1 CD-ROM holds 2048 bytes of data.
The 304 "lost" bytes are used for sector addressing, synchronization,
and error correction.
If you read a MODE-1 CD-ROM sector in "cooked" mode, you get 2048 bytes
of data. When you write that to a CD-R or CD-RW, the error correction
bytes are reconstructed. If you read that sector in "raw" mode, you get all
2352 bytes of data. If you simply wrote those bytes to a CD-R, any errors
that slipped past the CIRC encoding while reading would be propagated,
and could result in generation loss (see sections (2-17) and (3-18)).
There are times when you don't *want* to have the error correction
reconstructed. For example, some games deliberately distort the error
correction bytes as a form of copy protection. See section (2-4).
The recording software has the option of error-correcting the 2048 bytes
of CD-ROM data and even regenerating the ECC data. Doing either reduces
the risk of generation loss; doing both eliminates the risk by effectively
doing a "cooked" read and write. (Apparently some drives will error-correct
CD-ROM data for you even in "raw" mode.)
To copy a disc in "raw" mode, you need the right reader, the right writer,
and the right software. Programs like CloneCD specialize in "raw" copies,
but require that the CD-ROM drive used to read discs and the recorder used
to write them support "raw" reads and writes. The web page for CloneCD
(6-1-49) is a good place to look for a list of capable hardware.
"RAW DAO-96" refers to a method for writing "raw" 2352 byte sectors with 96
bytes of associated P-W subcode channel data (section (2-6)). This is useful
for copying discs with CD+G, CD-Text, and certain forms of copy protection.
"DAO" refers to its use in combination with disc-at-once recording.
There's also "RAW DAO-94", which is the same as DAO-96 except that the
two bytes of Q channel CRC data are always generated by the recorder, and
"RAW DAO-16", which includes only the P-Q subcode channels.
Subject: [3-52] How do I do cross-fades between audio tracks?
(2000/12/02)
A "cross-fade" is a smooth transition from one track into another. If done
properly, with compatible music, the tracks appear to blend into one another.
Some of the fancier recording applications, such as Sound Forge
(http://www.sonicfoundry.com/) and Waveburner (6-1-55), will do cross-fades.
An "Advanced CrossFading" plug-in for Winamp can do them; set the output
device to a file on disc (with a "disk writer plug-in"?), and play the
music you want to record.
It's important to use disc-at-once recording when writing the tracks to
avoid having two-second gaps inserted. See section (3-26).
Subject: [3-53] How do I create a CD with my favorite songs on it?
(2000/12/02)
If you want to create a CD that includes songs from several other CDs,
there are two basic approaches:
(1) Use a program, like Easy CD Creator Deluxe (6-1-26), that allows you
to select tracks from multiple CDs on the layout screen. The "wizard"
can walk you through the process.
(2) Extract the tracks you want to your hard drive, perhaps with a
program like Exact Audio Copy (6-2-12), and then write them all at once.
The former is a little easier, and requires less disk space. The latter
allows you to use disc-at-once recording, which prevents the recorder from
inserting a two-second gap between each track.
Subject: [3-54] How do I record directly onto CD from a microphone?
(2001/03/02)
If you have a stand-alone audio CD recorder, this should be straightforward.
Either you have a microphone input or you don't.
On a computer, you probably don't want to do this. The greatest advantage
of using a computer-attached recorder is that you can edit the result
before recording it. CD-R is write-once media, so if you make a mistake,
you can't fix it later.
If you're determined to do this, Roxio's Spin Doctor (part of Easy CD
Creator) can do what you want. Connect the microphone to the input on
the PC sound card, start up the software, and record when ready.
The situation on non-PC platforms is similar: you can do it if your
software supports it.
Subject: [3-55] Is it okay to record a CD from MP3?
(2001/04/19)
Yes, though the quality won't be as good as if you had recorded directly
from the original CD.
MP3 is a "lossy" compression format, meaning that it gets its exceptional
compression ratios by throwing some of the data away. (MP3 can get a
10:1 reduction with hardly any degradation in audible quality; "lossless"
compression is hard-pressed to do better than 2:1 on 16-bit samples.)
The clever part about MP3 is the way it figures out what parts of the
audio to throw away and what to keep, based on a model of human hearing.
Because it's a lossy format, every time you compress something you lose some
of the quality forever. The smaller you compress it, the more you lose.
The loss is more easily audible on some music than others, and if your
equipment (or your ears) aren't very good you may not notice it at all.
If you like to copy CDs by ripping them into MP3 format and then recording
them to MP3, be aware that your copies aren't quite as good as your
originals. At 160Kbps it's going to be hard to notice, but at 64Kbps it
should be easy to tell the difference between the original and the copy.
(Side note: if you want to do a double-blind test, play the original and
the duplicate in random order for somebody else, and ask them if they can
identify the original music. The test isn't to tell that the discs sound
*different*, but rather to figure out which disc sounds *better*.)
For more information about lossy and lossless audio compression, see:
- http://www.faqs.org/faqs/compression-faq/
- http://www.mpeg.org/
- http://www.mp3.com/
For some tutorials on converting between MP3 and other formats, see
section (3-27).
Subject: [3-56] How can I test a disc image before recording?
(2002/02/25)
You have a few options.
You can do a trivial check of an ISO disc image with WinImage. See
section (6-2-2).
Under Linux, you can mount it via the "loopback" filesystem, e.g.:
"mount ./cdimg.iso /mnt/test -t iso9660 -o loop".
Under DOS/Windows, you can "SUBST" a directory to make it look like a
drive, e.g. "SUBST J: \goodies\NewCD" will make the contents of
"\goodies\NewCD" appear to be mounted on the J: drive. This is a useful
way to test autorun.inf files.
A more robust approach under Windows is to use a CD emulator.
These programs usually use their own proprietary disc formats, but
some converters are available (e.g. http://www.bluebitter.de/),
and some can mount ISO images directly. Examples include
Microtest Virtual CD (http://www.virtualcd-online.com/), Paragon
CD Emulator (http://www.cdrom-emulator.com/), and Daemon Tools
(http://www.daemon-tools.com/).
Subject: [3-57] How do I clear the "read-only" flag under Windows?
(2003/03/25)
If you write files to a CD-R with conventional recording and then try
to copy them back, under Windows the files will all have their "read
only" flags set. This can be annoying for documents you want to update.
The files aren't written to the disc as "read only". There isn't any such
permission flag in the filesystem. They're simply presented that way
by Microsoft operating systems. Mac OS deals with this in a nicer way,
showing unlocked files on write-protected media, rather than the dopey
Microsoft approach of showing write-protected files on unlocked media.
You can avoid this situation entirely by using packet writing (where
you just copy files to the disc like a big floppy, e.g. with DirectCD),
which preserves the file attributes, or by using backup software, which
will restore the files to their original state. Stuffing the files into
a ZIP archive works too, but may be less convenient than other approaches.
If you've already got the read-only files, changing them back to read-write
isn't too hard. Some approaches:
If you're using Win2K or WinXP, right-click on the top-most folder(s),
and un-check the read-only box. You will be asked if you want to apply
the change to all files and folders in the folder. Say "yes".
For DOS or older versions of Windows, from a DOS prompt run "ATTRIB -R *.*
/S" on every subdirectory with read-only files in it.
If you prefer a Windows application, try "ReadOnly" from
http://www.sente.co.uk/downloads.htm. They also have a more sophisticated
application called "FlagRASH".
If you can boot into Linux, su to root, mount the volume as vfat, cd
to the directory in question, and do "find . -print | xargs chmod +w"
to enable write permission for all files in the current directory and in
all subdirectories. If you've got the GNU utilities, use "find . -print0
| xargs -0 chmod +w" instead, because it'll work correctly on files with
spaces in the names. (Of course, if you're a Linux user, you could just use
mkisofs with the appropriate options and have Rock Ridge file permissions
that match the originals, but this is a Windows question.)
Subject: [3-58] How do I share a CD recorder across a network?
(2002/12/02)
There is no general way to access a CD recorder on a remote machine.
You need to have software running on the machine with the recorder.
This might be something as simple as DirectCD, to provide a filesystem
that Windows can write files directly to, or something fancy that accepts
disc images and queues them for recording.
Ahead's NeroNET (http://www.nero.com/) provides a client/server model
for sharing CD recorders. See also CD Studio+ (section (6-1-6)).
Subject: [3-59] How do I write a large file across multiple discs?
(2003/03/05)
This is usually referred to as "spanning", and is a standard feature of
most backup software (see section (6-7)). With a little extra effort,
you can accomplish the same thing with standard software.
One approach under Windows is to create a ZIP archive with WinZip
(http://www.winzip.com/), and then use the "Split" item on the Actions
menu to break the archive into pieces small enough to fit onto CD-Rs.
The feature was originally created to split archives across multiple
floppy discs, but it works just as well with 650MB pieces.
On a UNIX system, use the "split" command, e.g. "split -b 650m myfile".
Write each file to a separate disc, and combine them later with "cat".
These commands have been a standard part of UNIX for just about forever,
so you should have no trouble finding them.
Subject: [3-60] What's the safest, most reliable way to write data to CD-R?
(2004/04/15)
The best approach is the one that leaves you with a 100% readable disc
today and a few years down the road. The key ingredients are:
Use quality media
Saving a few pennies today could result in big headaches later on.
Some of the cheap bulk brands are good-quality "unbranded" media
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