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Section 3 of 6 - Prev - Next
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Visit http://www.digitalexperience.com/cards.html for a feature comparison
of many different models.
An inexpensive S/PDIF card available from Computer Geeks
(http://www.compgeeks.com/) was evaluated by some newsgroup readers in
mid-1998. Apparently there were some problems with the physical dimensions
of the card (too wide for some PC slots), the documentation is poor, and
the voltage level for both input and output was TTL instead of standard
S/PDIF. You're probably better off with one of the established brands
unless you're sure about what you need.
You should record from the DAT onto your hard drive, and then record the CD
from there. If you try to record directly from DAT you'll likely end up
with a lot of wasted CD-Rs due to buffer underruns or minor mistakes. You
should use Disc-At-Once recording for best results.
One issue you need to be aware of is that some older DAT recorders can
only record at 48KHz, while CDs are recorded at 44.1KHz. If this is the
case with your equipment, you will have to do a sample rate conversion.
The DSP on cards like the ZA2 will do this for you, or you can use an
audio editing program like GoldWave or Sound Forge.
There *are* CD-R drives that have analog inputs, and can record directly
from audio sources. See section (5-12).
If you use a DAT and haven't been to the DAT-heads home page, you should
definitely check out http://www.atd.ucar.edu/rdp/dat-heads/.
If you want to manipulate audio DATs directly from your computer,
you need a DDS drive with special firmware. The SCSI DDS drives
that are typically sold for backups don't have the firmware required
to handle DAT tapes. Most SGI workstations can do this, and Mac
users should check out http://www.demon.co.uk/gallery/StudioDAT.html
[link dead?]. If you have an Archive Python DDS drive, check out
http://www4.informatik.uni-erlangen.de/~eckert/. Reputable Systems
(http://www.reputable.com/) sells DDS-2 drives with SGI firmware,
Archive/Conner/Seagate model CTD-8000HS.
Some other drives can be supported with appropriate firmware updates. See
http://www.trygve.com/playaudiodat.html.
An interesting combination of technologies is the DAT-Link, formerly
available from http://www.tc.com/. It connects to the digital connectors
on the DAT machine (or MD, DCC, or CD player) and the SCSI interface on
a computer. The device can be controlled from other computers on a network.
If you're interested in mastering production audio CDs, you should take
a look at http://www.sadie.com/.
Subject: [3-14] How do I put audio and data on the same CD?
(2001/01/10)
There are two ways to do this. The first is to put the data on track 1 of
the CD, and audio on the next several tracks (discs created this way are
referred to as "mixed-mode" CDs). The CD-ROM drive will automatically look
at track 1 and ignore all other tracks, so you'll be able to get at the
data and -- depending on the operating system -- will be able to play the
audio tracks. Remember that all of the tracks, both audio and data, need
to be recorded in a single session. See section (3-2).
The down side of this is that audio CD players may attempt to play track 1,
which can be obnoxious or downright harmful to audio equipment. Most
modern CD players are smart enough to ignore data tracks, so this won't
usually be a problem.
The other approach is to create a multisession disc with the audio tracks
in the first session and the data track in the second. This is how CD
Extra (the format formerly known as CD Plus) works. Audio CD players only
look at the first session, and CD-ROM drives are (supposed to) start with
the last session, so it all works out. Sony Music has some pages at
http://www.cdextra.com/.
(NOTE: it appears that in some situations a Macintosh will not handle
multi-session audio/data CD-R discs correctly. For example, a G3 with a
DVD-ROM drive running Mac OS 8.6 works fine, but a G4 or iMac running Mac OS
9 will reject the disc as unreadable. The same system will handle pressed
discs correctly -- only CD-Rs fail. The reason for this is uncertain,
but it may be possible to work around it by disabling the system's audio
CD extension when you want to read the data portion.)
A common question is how to write the audio in the first session without
gaps between tracks, because you can't use disc-at-once recording.
(If you did use DAO recording, the disc would be closed, and you wouldn't
be able to write the data track). With the right hardware and software,
you can do "session-at-once" recording to write the audio without gaps.
For example, if you're recording with Nero and SAO-capable hardware,
you just select disc-at-once mode but don't select "finalize CD".
What happens when you try to play one of these as audio in your CD-ROM
drive? As with most things multisession, it depends on your drive. (The
player that comes with Plextor CD-ROM drives does the right thing. If
you're using a different drive, you're on your own.)
There's actually a third way to do this that involves putting the data
track into the extended pregap of the first audio track. Instead of the
audio starting at minute:second:block 00:02:00, the data starts there, and
the audio is written after. The pregap is adjusted accordingly. This
method never gained popularity because some drives started playing at
00:02:00 regardless. There doesn't seem to be a way to do this on CD-R.
Some CDs perversely put audio in the pregap. You can play it by starting
to play track 1, then holding the "reverse" button until it seeks all
the way to the start of the disc. Some older digital audio extraction
programs would just ignore the "hidden" audio, but most newer ones will
extract the entire track.
For example, _Factory Showroom_ by "They Might Be Giants" looks like this:
TRACK 01 AUDIO
INDEX 00 00:00:00
INDEX 01 01:01:00
TRACK 02 AUDIO
INDEX 00 04:52:10
INDEX 01 04:52:10
TRACK 03 AUDIO
[...]
Index 01 on track 01 is usually 00:02:00. Holding down the reverse button
backs the time up to -1:03. This disc actually causes one of my Windows
machines (Win98SE with a Plextor 12/20 CD-ROM) to read the disc incessantly,
making it impossible to play the disc or extract audio tracks.
See section (3-36) for more information on "hiding" audio tracks.
Subject: [3-15] How do I make a bootable CD-ROM?
(2001/09/10)
On a Mac, this is reasonably straightforward. A CD can be bootable if it
has a bootable system folder on it. Tell the recording software that you
want to make the CD bootable; this usually involves clicking in a checkbox
before burning the first session. Then, copy a bootable system folder onto
the disc. An easy way to create an appropriate system folder is to launch
the system installer, tell it you want to do a "Custom" install, choose the
"Universal System" option, and then install it onto the CD source volume.
One caveat: any control panels or extensions that want to write to their
preferences files will fail. You may need to write from a system folder
that has been booted at least once.
Detailed instructions for creating a bootable CD with Toast can be found at
http://www.roxio.com/en/support/toast/toastbootable.html.
Holding down the 'c' key while booting will cause the Mac to boot from an
internal CD-ROM drive. Alternatively, the "Startup Disk" control panel
will allow you to select a CD-ROM.
The rest of the section applies only to PCs, which are more challenging.
The BIOS or SCSI card on most newer machines support booting from CD-ROM,
but on many older machines it's just not possible. Phoenix (the BIOS
developer) and IBM have created the El Torito standard for doing this sort
of thing. When the machine boots, if the BIOS recognizes a bootable image
on the CD-ROM, it maps that image onto the A: floppy drive. (Depending on
implementation, A: will move to B: and B: will go away.) From that point
onward, it's just like booting a floppy.
Not surprisingly, the way you create a bootable CD-ROM is to take an image
of a bootable floppy disk and write it in a specific way onto the CD.
Many of the current CD writing programs, including Easy CD Creator and
CDRWIN, will do the hard work for you.
A very nice page with lots of technical and how-to information:
http://www.nu2.nu/bootcd/
You can find El Torito specifications and a "how to" guide at:
http://www.phoenix.com/products/specs.html
http://www.phoenix.com/products/wp.html
If you like to do things the hard way, step-by-step procedures with
varying levels of detail can be found here:
http://www.cdpage.com/Compact_Disc_Variations/bootablecdarticle.htm
http://www.ozemail.com/~rossstew/drs/bootcd.html
http://goldentimes.net/bootcd01.htm
http://www.fadden.com/doc/bootcd.txt
You can learn how to make bootable Win95b/Win98 CD-ROMs here:
http://www.heise.de/ct/Service/English.htm/99/11/206/
When booting the PC, you may need to change the boot order in the BIOS from
the typical "A, C" to "A, SCSI, C", and configure the SCSI interface to
attempt to boot from CD. On some adapters, the boot-up SCSI bus scan may
take an extra second or two while the interface tries to determine if a
bootable CD-ROM is present.
Some programs insist that bootable CD-ROMs be written in plain ISO-9660
format, not Joliet. One way around this is to write the bootable portion
in the first session, and then write the rest of the data in a second
session. However, not all PCs will boot a multisession disc. A better
approach is to use a program like mkisofs (6-1-10) to create the image.
The El Torito standard allows CD-ROMs to have more than one bootable
image, but few applications support creating such images. You can use
mkisofs with the "-eltorito-alt-boot" option to do this.
If you're having trouble finding drivers for your CD-ROM drive, try the
Win98 boot disk, or http://www.drivershq.com/.
Subject: [3-16] How do I convert home movies into video on CD?
(2002/11/22)
This topic is largely outside the scope of this FAQ, so I'm not going to go
into much depth. The Usenet newsgroup news:rec.desktop.video is more
applicable. I'm not aware of an FAQ for that group, but the links found at
http://www.videoguys.com/jump.htm will get you started.
You need a capture device to transfer the video to your hard drive.
Capturing high-quality video can eat up 2MB or more per *second* of video
at full resolution (640x480x24 at 60 fields per second for NTSC) with a
reasonable degree of compression, so this isn't something to be undertaken
lightly. The lower your quality requirements, the lower the bandwidth
requirements. On a fast machine, you can even get away with just a TV
tuner card, using the software from http://www.winvcr.com/.
If MPEG is your only interest, you might be better off with an MPEG-only
card rather than a hobbyist video capture board. http://www.b-way.com/
and http://www.darvision.com/ are good places to look. The Broadway
card has been given high marks for quality.
Once you've captured the video, you'll probably want to edit it, at least
to clip out unwanted portions or add titles. Packages for doing this,
like Adobe Premiere and Ulead MediaStudio, are usually included with the
capture card. These will also let you adjust the resolution, color depth,
and compression quality to output the video so that it's suitable for
playback on double- or quad-speed CD-ROM drives.
You can convert AVI files to MPEG and vice-versa with a program from Ulead
(see http://www.ulead.com/), Xing Technologies, or several other vendors.
You should be able to create QuickTime or AVI movies using the compression
codec of your choice from the video editing software. A good choice is
TMPGEncoder, from http://www.tmpgenc.com/e_main.html.
Once created, you can write the AVI, MPEG, or MOV (QuickTime) file to a
CD-ROM like you would anything else. If you'd like to view the disc in a
DVD player or other VideoCD playback device, read the next section. Note
that not all DVD players are capable of reading CD-R media, so if VideoCD
on CD-R playback is important to you, check the DVD player feature set
before you buy.
Converting directly to DVD format is pretty reasonable now, with relatively
inexpensive DVD-R recorders and authoring software. Some Macintoshes ship
with iMovie/iDVD and a DVD recorder built in.
The MPV (MultiPhoto/Video) specification was announced in November 2002.
It's purpose is to define a standard way of storing pictures, videos,
and audio on digital media. This could eventually be the preferred way
to store movies on a disc. See http://www.osta.org/mpv/.
Subject: [3-16-1] How do I create a VideoCD from AVI or MPEG files?
(2001/07/23)
This section assumes you already have the video captured on the hard drive of
your computer. If you don't know how to do that, read the previous section.
The goal is to create a White Book VideoCD, which can be viewed on any
VideoCD-compatible playback device. Most PCs and Macs have some amount
of support, as do many DVD players, so even if you can't find a dedicated
VideoCD player or CD-i box you should be able to find a way to watch them.
VideoCDs can only be read by CD-ROM drives capable of reading CD-ROM/XA
discs. If your drive doesn't claim to support PhotoCD, you're probably
out of luck, but this is rare. Microsoft's ActiveMovie (now Windows Media
Architecture) and Apple's Video Player can play movies off of a VideoCD.
Depending on the software you have installed, you may get a nice player,
or you may need to examine the disc manually and open the ".dat" files in
the "mpegav" directory.
If you were hoping to play your VideoCD on a DVD player, you should read
about VideoCD and CD-R/CD-RW compatibility with DVD players first. See
http://www.dvddemystified.com/dvdfaq.html#2.4.5 and section (2-13).
CD-R software packages like Easy CD Creator, Nero, and GEAR can write
MPEG-1 movies onto a CD in the necessary format. You have to be careful
when creating the MPEGs, because if the encoding parameters (frame rate,
number of pixels, etc) don't match the VideoCD parameters you may have
trouble getting the CD writing software to accept the movie.
You can include still frames from JPEG images as well. Most VideoCD
creation software provides a way to organize "assets"
John Schlichther's "avi2vcd" combines standard tools into an easy-to-use
program for Win95 and NT. You can use it to convert an AVI file into a
VideoCD-compatible stream. http://home.cogeco.ca/~avi2vcd/
Another choice is TMPGEncoder, from http://www.tmpgenc.com/e_main.html.
If you're running Linux you should take a look at Bernhard Schwall's
"avi2yuv" program. It converts M-JPEG movies created with popular video
capture boards into a format accepted by the Berkeley MPEG-1 and MPEG-2
encoders (ftp://bmrc.berkeley.edu/pub/mpeg/). The README for avi2yuv lists
the additional software packages (all of which are free and run under
Linux) needed for creating MPEG movies complete with sound. Most (all?) of
the utilities can also be built to run under DOS.
http://sunsite.unc.edu/pub/Linux/apps/graphics/convert/.
"iFilmEdit", from http://www.cinax.com/Products/ifilmedit.html, will
convert MPEG to VideoCD, and can reportedly convert a VideoCD .DAT file
back into a plain MPEG file.
"VCDGear", from http://www.vcdgear.com/, converts between .dat and .mpg.
http://www.vcdhelp.com/ has software and information.
The "VideoCD Cook Book" at http://www.flexion.org/video/VideoCD/0.html
is worth a look.
Easy CD Creator, as of v3.x, requires that an MPEG MCI driver be installed in
the system (unlike CD Creator, it doesn't come with Xing's MPEG software).
The popular VMPEG 1.7 doesn't quite work: ECDC can't see the audio, and
you're not allowed to select the frame to view when shuffling streams
around. If you have VMPEG installed as the MCI driver -- select "About
ECDC" from the Help menu to check -- you need to *remove* VMPEG and then
install ActiveMovie. (I removed under Win95 it by going into the Advanced
section of the Multimedia control panel, expanding "Media Control Devices",
selecting vmpegdll, and clicking on "Remove", but you may be able to use
Add/Remove Programs instead.) ECDC v3.x was very picky about the video
streams; v4.02 is much better.
Finally, you should be aware that MPEG playback is rather CPU intensive, and
it's possible to create movies that don't play very well on slower machines
(90MHz Pentium, 68K Macs) without hardware support. Machines built in 1997
or later shouldn't have trouble.
Subject: [3-16-2] How do I create an SVCD?
(2000/11/13)
First, read about creating a VCD in section (3-16-1).
Next, read http://www.uwasa.fi/~f76998/video/svcd/overview/.
The links near the end of the document point to some pages with SVCD
authoring instructions. Programs such as Nero Burning ROM (6-1-28) and
Enreach I-Author (6-1-61) are able to create such discs.
Subject: [3-16-3] How do I create an AVCD?
(2002/07/29)
Some discs have been produced that call themselves "AVCD", as in
audio-video CD. For example, Kylie Minogue's "Fever" CD was released
as a two-disc set in Asia. Disc one was the "Fever" audio CD, disc
two had four VideoCD video tracks and five bonus audio tracks.
If you put disc two into a CD player, you would hear nothing for track 1
(which holds the VideoCD filesystem) or tracks 2 through 5 (the video
data). If you fast-forwarded to track 6, you would hear music.
If you put disc two into a VideoCD player or compatible DVD player,
you would be treated to the first video track. By skipping forward
you could get to the later video tracks and eventually play the audio
tracks.
This makes perfect sense until you try to figure out how the same audio
track is being played on a CD player and on a VideoCD player. If you
try to create a VideoCD with extra audio tracks, the VideoCD player
will not find them.
The trick used by the AVCD publishers is to encode the audio tracks twice.
The songs are present both as Red Book CD audio tracks and as VideoCD
compressed audio. A directory called "CDDA" holds files with names like
"AUDIO06.DAT" that contain compressed audio. Unlike the video tracks,
these don't actually correspond to tracks on the disc.
To create such a disc, you would need VideoCD authoring software capable
of incorporating audio tracks. You could then record the VideoCD while
leaving the session open, and append the audio tracks using track-at-once
recording. Better results would be obtained by writing the video and audio
tracks with disc-at-once recording, but that might require a greater level
of VideoCD support than most recording applications currently provide.
See section (3-16-1) for more tips on VideoCD.
Subject: [3-17] How can I burn several copies of the same disc simultaneously?
(2003/07/08)
You can if you have several CD-R drives and the right software. Two
examples are CD Rep from Prassi Software (section (6-1-21)) and DiscJuggler
from Padus (section (6-1-27)). [The Prassi product appears to have been
discontinued.]
Both products are SCSI multiplexors. You use your existing CD writing
application (such as Easy-CD Pro 95) like you normally would, and the
program sends the same commands to each of the CD-R drives. There are a
number of limitations, notably that all devices must use the same command
set and may need to have the same firmware revision. There may also be
limits on the number of drives you can have attached at once.
DiscJuggler bills itself as "the professional CD Duplicator", CD Rep as
"the ultimate professional recording solution". If you're interested in
either of these, you should read the web pages for both, and compare the
features available.
There are several hardware-based solutions to this, including CD-R units
that support daisy-chaining, and control units that vary from the simple (a
handful of units wired together) to the complex (robotic arms to move discs
around). Most cost more than a Hyundai.
See http://www.cd-info.com/CDIC/Technology/CD-R/duplication.html for an
overview of several different hardware solutions, or visit a vendor web
page like http://www.princetondiskette.com/.
Subject: [3-18] Can I make copies of copies?
(2002/12/09)
The following was part of an e-mail message from Jeff Arnold back in
mid-1997:
"I do not recommend making "copies of copies" with SNAPSHOT. The reason
this does not always work is because many CDROM readers do not perform
error correction of the data when doing raw sectors reads. As a result,
you end up with errors on the copy that may or may not be correctable.
When you make a second-generation copy of the same disc, you will make a
disc that has all of the errors of the first copy, plus all of the new
errors from the second reading of the disc. The cumulative errors from
multiple copies will result in a disc that is no longer readable."
This initially generated some confusion, so further explanation is needed.
The heart of the problem is the way that that the data is read from
the source device. When a program does "raw" sector reads, it gets the
entire 2352-byte block, which includes the CD-ROM error correction data
(ECC) for the sector. Instead of applying the ECC to the sector data,
many drives just hand back the entire block, including any errors that
couldn't be corrected by the first C1/C2 layer of error correction (see
section (2-17)). When the block is written to the CD-R, the uncorrected
errors are written along with it.
The problem can be avoided completely by using "cooked" reads and writes.
Rather than create an exact duplicate of the 2352-byte source sector, cooked
reads pull off the error-corrected 2048-byte sector. The CD recorder
regenerates the appropriate error correction when the data is written.
Some drives and some software will error-correct the 2048 bytes of CD-ROM
data read in "raw" mode. This limits the risk of generation loss to errors
introduced in the ECC bytes. If the software also regenerates the ECC,
it is effectively emulating "cooked" reads and writes in "raw" mode.
This begs the question, why not just use cooked writes all the time?
First of all, some older recorders (e.g. Philips CDD2000 and HP4020i)
didn't support cooked writes. (Some others will do cooked but can't do
raw, e.g. the Pinnacle RCD-5040.) Second, not all discs use 2048-byte
MODE-1 sectors. There is no true "cooked" mode for MODE-2 data tracks;
even a block length of 2336 is considered raw, so using cooked reads won't
prevent generation loss.
It is important to emphasize that the error correction included in the data
sector is a *second* layer of protection. A clean original disc may well
have no uncorrectable errors, and will yield an exact duplicate even when
copying in "raw" mode. After a few generations, though, the duplicates are
likely to suffer some generation loss.
The original version of this quote went on to comment that Plextor and Sony
CD-ROM drives were not recommended for making copies of copies. The reason
they were singled out is because they are the only drives that explicitly
warned about this problem in their programming manuals. It is possible
that *all* CD-ROM drives behave the same way. (In fact, it is arguably the
correct behavior... you want raw data, you get raw data.)
The final answer to this question is, you can safely make copies of copies,
so long as the disc is a MODE-1 CD-ROM and you're using "cooked" writes.
Copies made with "raw" writes may suffer generation loss because of
uncorrected errors.
Audio tracks don't have the second layer of ECC, and will be susceptible to
the same generation loss as data discs duplicated in "raw" mode. Some
drives may turn off some error-correcting features, such as dropped-sample
interpolation, during digital audio extraction, or may only use them when
extracting at 1x. If you want to find out what your drive is capable of,
try extracting the same track from a CD several times at different speeds,
then do a binary comparison on the results. PC owners can use the DOS "FC"
command to do this, as described in section (3-3).
It's worth noting that the C1/C2 error correction present on all types
of CDs is pretty good, so it is entirely possible to make multi-generation
copies with no errors whatsoever. The "cooked" approach for CD-ROMs just
happens to be safer.
Subject: [3-19] How can I compress or encrypt data on a CD-ROM?
(2003/01/13)
The easiest way is to use your favorite compression or encryption utility
and process the files before putting them on the CD. However, this isn't
transparent to the end user.
CRI-X3 enables programs like DoubleSpace to work on a CD. It's intended
for a publisher or for significant internal use, and the licensing is priced
accordingly. See http://www.cdrominc.com/. (Side note: the company filed
patent infringement suits against Traxdata and CeQuadrat in Sep 1998 for
distributing CD compression software. This might account for the dearth
of similar applications.)
A straightforward solution is to write all of the files onto the disc
as .ZIP files, and then use ZipMagic (formerly ZipFolders) to view the
contents. It can be found at http://www.ontrack.com/zipmagic/.
PGP at http://www.nai.com/ (was http://www.pgp.com) has some good
encryption software, but none of it seems directly applicable to software
distribution. PGPdisk, available for the Mac, might be useful but it isn't
clear whether it can be used to distribute CD-ROMs.
ScramDisk, from http://www.scramdisk.clara.net/, writes files into
encrypted "containers" on disk. It can be used with CD-ROMs, runs under
Win95 and Win98, is free, and even includes source code.
http://www.c-dilla.com/ had information on CD-Secure 2, which allowed
publishers to distribute network-licensed or "pay for the parts you
need" products, and CD-Compress 2, which provides a way to compress data
transparently on production CDs. The company is now part of Macrovision.
EnCrypt-CD encrypts the blocks as they are written to CD. It's a shareware
product, available from http://www.shareit.com/programs/102046.htm.
Encrypted Magic Folders from http://www.pc-magic.com/ claims to
transparently encrypt data as it's being used. Whether it would work from
a CD-ROM isn't stated.
http://cd-lock.com/ offers Blowfish encryption and scrambled filenames.
End users don't need to install software to decrypt the disks if they're
running Win2K or WinXP. (Appears to be related to pc-magic.com, above.)
You can install a cryptographic filesystem (called "CFS") under Linux; see
http://www.linuxdoc.org/HOWTO/Security-HOWTO-6.html#ss6.10. Create a
crypto-fs, copy your data onto it, then use mkisofs with Rock Ridge
extensions enabled to create an ISO-9660 disc image of the encrypted data.
Burn the image to CD-ROM.
You may be able to use E4M, from http://www.e4m.net.
BestCrypt, from http://www.jetico.com/, lets you create encrypted virtual
volumes in a file that can be stored on CD-R media.
You can get PC Guardian's CD-ROM encryption from http://www.pcguardian.com/.
WinDefender, available from http://www.RTSecurity.com/products/windefender,
provides transparent CD-ROM encryption from Windows.
Dynamic-CD can encrypt and password-protect CD-ROMs. See
http://www.dynamic-cd.com/.
Subject: [3-20] Can I do backups onto CD-R?
(2001/09/26)
Yes. See section (6-7) for software.
Of course, it's not really necessary to use special software if you're just
backing up your data files. Most CD creation programs will allow you to
copy arbitrary files onto CD-ROM, and by using the Joliet standard or the
UDF filesystem you can preserve long filenames. Unfortunately, if you're
not using packet writing, the individual files may show up as read-only
under DOS and Windows, so write permission must be re-enabled by hand when
the files are restored. With packet writing applications like DirectCD
or PacketCD, the correct file permissions are maintained.
(See section (3-57) for instructions on clearing the read-only flag.)
One thing to be careful of on Windows-based PCs: most programs that put
files on CD don't preserve the *short* file names that are automatically
generated for files with long file names. This presents a problem because
the short form is often stored in the Registry and INI files instead of the
long form (try searching your Registry for "~1"). When your system is
restored, it may not be able to find the files anymore.
A way to work around this is to use a backup program that understands only
the short filenames, and save the long ones with LFNBK. A program called
DOSLFNBK at http://www8.pair.com/dmurdoch/programs/doslfnbk.htm may be more
convenient than LFNBK.
Is CD-R better than, say, DDS-3 tapes? Maybe. Tape formats like DDS and DLT
hold considerably more than a CD-R, but because the drives are streaming
rather than random access, recovery of a specific file can be slower.
For backing up a large system or network, tapes are more convenient.
For making backups of a small system, especially one where access to older
versions of files is frequently desired, CD-R is the better choice.
Some people prefer CD-RW. For daily incrementals, CD-RW makes sense. For
weekly or monthly full backups, you probably want to retain the discs in
case file corruption or deletion goes unnoticed for some time.
The longevity of magnetic tape is well understood (around 15 years for
most formats). The longevity of CD-R is a little harder to quantify.
See section (7-5) for details.
Subject: [3-21] How do I automatically launch something? Change the CD icon?
(2002/10/15)
This can get surprisingly involved on a PC. The next few sub-sections
go into detail. For a Mac, the answers are pretty simple:
You can use the Macintosh equivalent of Autorun (QuickTime 2.0 Autostart)
to automatically launch an application or document on the Mac. The
"-auto" flag of mkhybrid (6-1-32) lets you specify this.
Changing the icon on the Mac can be done by using Toast to record a disc
image (record by "Volume" instead of "Files and Folders"). Change the icon
on the disc image file from the Command-I window in the Finder, then record
it.
Subject: [3-21-1] How does Windows "autorun" work?
(2002/10/15)
The "autorun" feature of Windows 95 and later allows a program to be executed
right after a CD-ROM is inserted. For this to work, the system must have
autorun enabled, and Auto Insert Notification ("AIN") must be turned on
for the CD-ROM drive. See section (4-1-1) for more information on AIN and
the use of "TweakUI" to modify settings. It may also be necessary, in some
configurations, to close the last session on the disc, or AIN will not work.
When preparing a CD-ROM for Windows, put a text file called "autorun.inf"
in the root directory that contains something like this:
[autorun]
open=filename.exe
icon=someicon.ico
When inserted, the CD-ROM will be shown in the "My Computer" window with
the specified icon. If the disc is inserted on a system with AIN and
autorun enabled, the program named on the "open" line will be launched.
Icons must be in Windows icon or bitmap format. You can't use a GIF
or JPEG. Make it square, 32x32 pixels. If you're going to be doing
a lot of these, you may want to try Axialis "IconWorkshop", from
http://www.axialis.com/axicons/.
There doesn't appear to be a way to specify custom icons for individual
folders.
Incidentally, the "root" directory is the top level of the disc, e.g. "D:\".
(If you viewed a directory hierarchy as a tree growing upward, the topmost
directory would be at the root of the tree.)
Here's a more complicated example:
[autorun]
open = setup.exe /i
icon = setup.exe, 1
shell\configure = &Configure...
shell\configure\command = setup.exe /c
shell\install = &Install...
shell\install\command = setup.exe /i
shell\readme = &Read Me
shell\readme\command = notepad help\readme.txt
shell\help = &Help
shell\help\command = winhlp32 help\helpfile.hlp
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