The process can be a bit more involved than that, and requires software that usually comes bundled with the drive. On a CD-R you can only write to each part of the disc once, so deleting files doesn't free up any space. There are other limitations as well.
With more traditional software -- necessary if you want broad compatibility -- you usually end up writing everything to the disc all at once. When you're doing the writing you can't interrupt the drive, and you can't reclaim the space you've used.
If you want to write your files in smaller bunches, you lose a fair bit of space every time you stop and start again. For DVD recorders, check out the Usenet newsgroup alt. You may be able to convert the contents into a lower-quality format though. Be wary of scams. See section Subject: [] What's the cheapest recorder and best place to buy media? I don't track prices. There are web sites dedicated to finding the lowest prices, and you can do a little research with a web browser, starting perhaps with the vendors listed in section Subject: [] Can I get step-by-step installation and use instructions?
There's no information of this type in the FAQ because there are far too many permutations of hardware and software, and the instructions would have to be updated with every new release of the software. In fact, many of the popular CD recording programs will decode the MP3s for you.
Section has more details. Subject: [] What does this term mean? Here are a few. Adaptec hosted by osta. If you have a recorder attached to your computer or a "professional" deck then the "music" blanks will work no better or worse than "data" blanks. See section for details. Subject: [] How do I learn more? If you're new to CD recording and are feeling a little lost, you may want to buy a book on the subject. Has a section on hardware installation. Subject: [] Why is this FAQ so far out of date?
Some sites like to make a copy of the FAQ with the version, date, and contact information stripped off the top in violation of section , which makes it hard to tell when it was last updated. If you are reading the current version, either the section hasn't been updated in a while check the date in the section , or something has slipped past me.
If you want news articles updated daily, try the sites in section Subject: [] How is the information physically stored? As with regular CDs, they employ a polycarbonate substrate, a reflective layer, and a protective top layer. Sandwiched between the substrate and reflective layer, however, is a recording layer composed of an organic dye.
Unlike regular CDs, a pre-grooved spiral track is used to guide the recording laser along the spiral track; this greatly simplifies recorder hardware design and ensures disc compatibility. Something to bear in mind is that the data is closest to the label side of the CD, not the clear plastic side that the data is read from.
A pressed CD has raised and lowered areas, referred to as "lands" and "pits", respectively. A laser in the CD recorder creates marks in the disc's dye layer that have the same reflective properties. The pattern of pits and lands on the disc encodes the information and allows it to be retrieved on an audio or computer CD player. See section for specifics. Discs are written from the inside of the disc outward.
On a CD-R you can verify this by looking at the disc after you've written to it. The spiral track on a minute disc makes 22, revolutions around the CD, with roughly track revolutions per millimeter as you move outward from the lead-in 23mm from the center to the outer edge at 58mm. If you "unwound" the spiral, it would be about meters 3. Subject: [] What is XA? They're not cheap! The discs are in Red Book format, but the low bit of the audio has additional information encoded in it.
It can have a Red Book compliant layer that is read by standard CD players, but to get the high-fidelity benefits you need a special player. Subject: [] How do I know what format a disc is in? CD-i discs will have a "Compact Disc Interactive" logo. The discs appear to use the standard Red Book format.
The discs can have two layers, one of which is in Red Book audio format, the other in a DVD-like format offering higher fidelity. See Subject: [] How does copy protection work? The goal is not to make it impossible to copy -- generally speaking, that can't be done -- but rather to discourage "casual copying" of software and music.
A separate but related issue is "counterfeit protection", where the publisher wants to make it easy to detect mass-produced duplicates. There are full CD pressing plants dedicated to creating counterfeit software the worst offender being mainland China , so this is a serious concern for the larger software houses.
A large percentage of games released in the past few years have been protected. A more recent innovation is copy protection for audio CDs, inspired by the rise of MP3 trading over the Internet.
This is more difficult to do, because the protection must allow correct behavior on a CD player but altered playback when being read by a CD-ROM drive.
The best that can be accomplished is to force the user to play the music in an analog format and then re-digitize it, resulting in an imperfect reproduction. Some people have questioned whether copy protection is legal.
In some countries it may not be. In the USA, the law allows "fair use" of copyrighted material, but does not require that the content provider make it easy for you to do so.
So while making a copy of a song for your own private use may be legal, there is nothing in the law that requires the publisher to make the material available in an unprotected format.
Copy protection has been around for many years -- some of the schemes employed on the Apple II were remarkably elaborate -- and has never been challenged on legal principle. The article also has some interesting quotes from the courts regarding the DMCA and DeCSS, notably this one: "We know of no authority for the proposition that fair use, as protected by the Copyright Act, much less the Constitution, guarantees copying by the optimum method or in the identical format of the original.
The next sections discuss data and audio individually. Subject: [] For anyone interested in protecting their own discs: don't bother. Copy protection, on the whole, does not work. If you have a major application, such as a game or CAD package, you may want to consider one of the commercially licensed schemes listed later, or heaven forbid the use of a dongle.
In general, though, if the disc can be read, then the contents can be copied. If you don't want somebody to make a copy of your stuff, then you'd better encrypt it A simple and commonly seen technique is to increase the length of several files on the CD so that they appear to be hundreds of megabytes long.
This is accomplished by setting the file length in the disc image to be much larger than it really is. The file actually overlaps with many other files. So long as the application knows the true file length, the software will work fine. If the user tries to copy the files onto their hard drive, or do a file-by-file disc copy, the attempt will fail because the CD will appear to hold a few GB of data.
In practice this doesn't foil pirates, because they always do image copies. And, no, none of the standard software provides a way to create such discs. One possible implementation, given sufficient control over the reader and mastering software, is to write faulty data into the ECC portion of a data sector. Standard CD-ROM hardware will automatically correct the "errors", writing a different set of data onto the target disc. The reader then loads the entire sector as raw data, without doing error correction.
If it can't find the original uncorrected data, it knows that it's reading a "corrected" duplicate. This is really only viable on systems like game consoles, where the drive mechanism and firmware are well defined. This can be defeated by doing "raw" reads. A more sophisticated approach is to write special patterns of data to the disc.
The stream of data that results, after EFM encoding, is difficult for some recorders to reproduce successfully, apparently because they don't choose correct values for the merging bits. This is often referred to on web sites as "writing regular EFM patterns" or "weak sectors". See section for details on EFM. A less sophisticated -- and no longer effective -- method is to press a silver CD with data out beyond where a minute CD can write.
Copying the disc used to require hard-to-find CD-R blanks, but now it's easy to use an overburned minute disc sections and The approach some PC software houses have taken is to use nonstandard gaps between audio tracks and leave index marks in unexpected places. These discs are uncopyable by most software, and it may be impossible to duplicate them on drives that don't support disc-at-once recording see section With the right reader and software, though, this isn't much of a problem either.
A method that enjoyed some popularity was non-standard discs with a track shorter than 4 seconds. Most recording software, and in fact some recorders, will either refuse to copy a disc with such a track, or will attempt to do so and fail. A protected application would check for the presence and size of the track in question. Some recorders may succeed, however, so this isn't foolproof. In one case, a recorder could write tracks that were slightly over three seconds, but refused to write tracks that were only one second.
There may be a limit below which no recorder will write. In such cases, the pirates need to remove the explicit check from the software itself. Putting multiple data tracks interleaved with audio tracks on a CD will confuse some disc copiers. However, it's difficult to actually use the data on those additional tracks. Sometimes the copy of a disc will have a different volume label. This usually only happens with file-by-file copies, not disc image copies, so checking the disc name is marginally useful but not very effective.
Modifying the TOC so that the disc appears to be larger than it really is will convince some copy programs that the source disc is too large. Some of the fancier technologies use non-standard pit geometry that cause players to read the data differently on consecutive attempts.
Sometimes the player sees a "1", sometimes a "0". If, when reading the track, the CD-ROM drive sees different data each time, the software knows that the disc is an original.
A duplicate disc will return the same data reliably. Some programs will examine the disc to try to determine if it's a CD-R. This doesn't work on all readers, and it's possible to disguise discs, so this isn't very effective. CloneCD section can copy many copy protected discs without trouble, given the right combination of reader and writer. Its main feature is "raw" reads and writes, which not all drives support.
It can be copied by CloneCD. A program could use this for copy protection by checking for the presence of the signature, and refusing to run if it's not there. Yet another variant is C-Dilla's SafeDisc. Their more recent product, SafeDisc 2, was the first to feature "weak sectors". The techniques making headlines in mid were developed by Macrovision and SunnComm More recent schemes attempt to modify the audio samples in ways that confuse CD-ROM drives into playing static.
The next few sections describe these approaches in detail. A web site at www. However, many CDs don't have the logo anywhere, so its absence doesn't prove anything.
Incidentally, if you're convinced that record companies and artists are raking in huge piles of cash from every CD they sell, you might want to take a look at an Electronic Musician article that talks about where the money comes from and where it goes. The ones that do make enough money have to pay for the rest. With figures like these, it's not surprising that the industry is taking steps to combat piracy. The basic idea is to create samples that sound like bursts of static, and scramble the ECC data around to make it look like an uncorrectable error.
There are two ways to play a CD on a computer, one analog, one digital. This may not hold true for newer Macintoshes -- it appears Mac OS 9 uses an entirely digital approach. Some recent CD player applications for the PC also do this.
The digital path requires reading the "raw" audio samples off of the disc, possibly modifying the data e. Until a few years ago, most CD-ROM drives did this very poorly, in part because the analog and digital data paths were logically distinct in the designers' minds.
See section for some additional notes. What Macrovision appears to be exploiting is the different handling of uncorrectable errors in audio samples on the digital path vs the analog path. This path deals with uncorrectable E32 errors by examining the samples that come before and after the error, and interpolating between them.
On a scratched-up CD, this means that, while you may not be hearing the exact samples that were originally recorded, you won't notice any glitches because they're smoothed over. This feature is definitely not something you'd want on a data CD-ROM -- interpolating pieces of your spreadsheet is not going to help you. In most CD-ROM drives, reading an audio sector with digital audio extraction is handled the same way that reading a data sector is: uncorrectable errors are left alone.
Instead of getting interpolated samples, you get to hear the original, scratched-up audio. This is why some CDs will play back just fine on your computer, but will come out all scratched up when you extract them with the same drive. The errors are there either way, but when using a desktop CD player the errors have been smoothed over by the logic in the analog output path.
Some drives may use interpolation during DAE at lower speeds. If so, it should be possible to "rip" a track from a copy-protected disc by reducing the extraction speed to 1x. Some people have suggested that software could be used to perform the interpolation on extracted music, stripping out the bits that the music companies added in. The trouble with this approach is that, once the data has been extracted, the CIRC encoding is no longer visible.
It may not be easy to tell where the glitches are. For example, it should be possible to create a low-level but rhythmic distortion that will be noticeable, annoying, and difficult to identify automatically. It's possible that any software specializing in defeating the copy protection would run afoul of the DMCA Digital Millenium Copyright Act , and the authors subject to fines and criminal prosecution.
Come to think of it, the preceding discussion might be illegal. How can you get a "clean" copy of a protected disc?
Some fidelity will be lost when converting from digital to analog and back again, which is what the industry is counting on. Of course, it has to be done at 1x, and the track breaks may have to be added manually, making it a potentially tedious affair. This extension to the "READ CD" command returns a set of flags indicating which bytes in an audio block were not corrected at the C2 level section An audio extraction application with access to this information could do its own interpolation across errors.
The "drive check" feature of cdspeed section reports on whether or not a drive is capable of returning "C2 pointers". The success or failure of audio CD copy protection hinges upon two factors: how effective is it at preventing "casual copying", and what sort of problems do the legitimate owners of audio CDs encounter when playing their discs?
Macrovision claims that their "golden ear" listeners were not able to tell the difference, though the test might be biased if the folks with the shiny lobes were using high-end CD players that did an especially good job of concealing uncorrectable errors. A legitimate technical concern is that the copy protection reduces the effectiveness of the error correction. In practice, if the "static" samples are relatively few and far between, the difference would be statistically insignificant.
One last piece of advice: do not assume that any disc that doesn't extract cleanly is copy-protected. There have been many, many postings on message boards from people who think they have found a protected disc, or how some specific piece of software can defeat the protection. Start with the more common reasons: the disc is dirty, the disc was poorly made, your CD-ROM drive is not that great at audio extraction, you're using software that isn't the best.
There are many reasons why ripping an audio track might fail. People have been having trouble getting clean audio for years.
See section for some advice if you're having trouble. Certain web sites notably cdfreaks. VXD will fix everything. So far, none of the sites that have claimed victory list a single SafeAudio-protected disc that was copied, most likely because -- at the time this was written -- there weren't any discs known to use SafeAudio. This phenomenon is not unheard-of; Sega's Dreamcast discs were widely reported to be copyable by a means that was quickly determined to be utterly ridiculous.
If the widely-touted CDFS. The results were inconclusive: clean versions of the tracks appeared on the net, but SunnComm claimed they came from an unprotected disc released on Australia. Their plan was to alleviate "fair use" concerns by allowing users to download MP3 versions of the songs after they registered the original.
The disc is multisession, and uses a hacked TOC, so track rippers and disc copiers have trouble dealing with it. SunnComm hasn't publicly stated any details.
In August , SunnComm announced v2. In mid, SunnComm announced "MediaMax CD3", a fancier implementation that allows computer users to play the CD through software supplied on the disc.
The software installs a memory-resident driver that prevents CD ripping from working on protected CDs. The protection can be foiled on Windows PCs by simply holding down the shift key for several seconds while inserting the CD. SunnComm announced they were going to sue the Princeton researcher, but quickly backed off. In December , following the XCP disaster see section , a flaw was discovered in MediaMax v5 that could allow malicious software to gain control of an affected computer.
The disc itself has an unusual construction. There is a heavy band at about the point where the music stops, and thin bands between tracks. These appear to be purely decorative and, I'm told, increasingly common on non-protected discs.
My CD player only saw 15 audio tracks. This feature alone makes the disc difficult to rip or copy, because the software doesn't see any audio tracks, and a CD-R copy would be full of tracks that even a CD player would see as data. It eventually sorted things out, but I get the sense the disc has been tweaked in ways that confuse the drive firmware. I tried using "Session Selector" to select the first session and then access the tracks.
I'd guess the firmware got confused. No dice -- the display showed 15 unselectable tracks and 1 MODE-2 data track. This choked when trying to read starting at block , so I tried again stopping at This resulted in a rather large WAV file, which I opened with Cool Edit -- revealing the entire contents of the disc, plain and clear.
Playback revealed no audible defects. I believe this worked because the sector extraction function ignores track and session boundaries, and just pulls the blocks straight off. Losing the track markers is annoying, but it's easy to add them back with something like CDWave section It would probably not be of help with a SafeAudio disc either. It has the advantage of allowing you to use standard tools, such as Exact Audio Copy section , which keeps the track breaks and can do fancy tricks to get the best extraction quality.
The method involves making the outer rim of the disc unreadable to the CD-ROM drive by drawing on it with a dry-erase marker or adding an adhesive sticker. This method, first posted in August of , resulted in a flurry of media attention in May of The first uses a non-standard TOC.
The position of the lead-out and the length of the last track were tweaked, resulting in a disc that appears to be only 28 seconds long. BMG Entertainment reportedly tried it and abandoned it.
In late , Midbar Tech announced a different approach. The approach appears to involve inserting frames of bogus control information into a relatively constant part of the CD audio stream. During playback, the extra frames are skipped. The result is bad samples that only appear in copies. That suggests that the bogus data doesn't appear as uncorrected data, but rather as valid data that is suppressed on the analog outputs.
This would seem to make digital copying difficult, but it would also make any form of digital playback impossible. No specific disc titles have been announced, but Sony has reportedly released a few titles in eastern Europe that use this.
Some personal notes on the early version CDS? Supposedly this is one of the BMG discs that was protected with Midbar's first product. The Plextor Plextools utility saw it as a single-session audio CD with 13 tracks, but when I asked it to play the disc it only saw the first 28 seconds of the first track, and stopped after playing just that much. My Panasonic CD "boom box" also thought the disc was only 28 seconds long, but it happily played past that point, and would let me select any track.
Recommended reading. The bulk of the music is on the CD, but a small but essential piece is streamed from a secure server over the Internet. The idea is to allow music publishers to distribute songs to the media and retail outlets ahead of scheduled releases. This was a response to songs appearing in MP3 form on the Internet before the CDs went into distribution. It will be reasonably effective for promotional copies of songs, though, where the goal is to prevent people from walking away with copies of the discs.
As an added bonus, because the music is streamed from a central location, it could have a digital watermark added. If say somebody at a radio station made an MP3 copy, it might be possible to trace the source of the MP3 file back to the source.
There is nothing on the product pages to suggest that such a scheme is currently in place. It's not clear if this is their own scheme or one licensed from another company. The light is converted to electrical impulses, the impulses drive the chip, and if all goes well the results are presented to the drive via an embedded light-emitting diode. Making an exact duplicate of the disc would be very difficult.
It's unclear whether this technology actually makes it harder to get a working copy of the contents. The scheme seems to essentially be a combination of an "uncopyable" disc and a hardware dongle, both of which have been around for years neither of which have brought an end to piracy.
XCP includes anti-piracy technology that acts to prevent you from copying it, and cloaking technology to prevent you from seeing it. As with other technologies of this type, disabling autorun or holding down the shift key while loading a CD will prevent the copy protection from loading. Because this protection is difficult to remove you must be very careful when handling Sony music CDs on your computer.
This produced a tremendous backlash against Sony BMG. It was used by enterprising game cheats to circumvent World of Warcraft's elaborate anti-cheating system, and a couple of viruses were using it to conceal themselves. After news of XCP became widely known, Sony BMG began offering a software download on its site that would identify affected systems by removing the cloaking, but wouldn't remove the rootkit entirely.
You could get the patch by filling out a marketing survey that -- according to Sony's privacy policy -- could lead to having your e-mail address added to their mailing lists. It appears to be connecting to a Sony web site to look for updated content.
There is some speculation that this could be used for tracking purposes, though Sony denies that they are doing so. A class-action lawsuit was filed on behalf of residents of the state of California USA in November , and similar actions were planned elsewhere. Use of the technology was suspended in November in response to public pressure. The CD recorder doesn't have to write the entire session at once -- you can write a single track, and come back later and write another -- but the session must be "closed" before a standard audio CD or CD-ROM player will be able to use it.
This provides a simple and fairly reliable way to write some data to a disc now and still be able to add more later. The trouble with using multiple sessions is that, every time you write a chunk of data, you incur a fairly substantial amount of overhead: 23MB after the first session, and 14MB for every subsequent session. This overhead lead to the development of "packet writing", which allows drag-and-drop recording, but works in an entirely different way see section Multisession writing was first used on PhotoCD discs, to allow additional pictures to be appended to existing discs.
Today it's most often used with "linked" multisession discs, and occasionally for CD-Extra discs. These require a bit more explanation. Well, that's how it's supposed to work. Most of the popular CD creation programs allow you to "link" one or more earlier sessions to the session currently being burned. This allows the files from the previous sessions to appear in the last session without taking up any additional space on the CD except for the directory entry. You can also "remove" or "replace" files, by putting a newer version into the last session, and by not including a link to the older version.
In contrast, when you put an audio CD into a typical CD player, it only looks at the first session. For this reason, multisession writes don't work for audio CDs, but as it happens this limitation can be turned into an advantage.
Some audio CD players do seem to be able to recognize all of the tracks on a multisession audio disc. Most do not. The only way to know for sure is to try and see. If you are planning to give an audio CD you create to others, it would be wise to write it in a single session. Adding a new session will cause the previous session to disappear. Quick recap: if you want to write some data to a CD-ROM now, and some more later, you write a single data track in multiple sessions or with packet writing.
If you want to write some audio tracks to a CD now, and some more later, you write multiple audio tracks in a single session. Subject: [] What are subcode channels? The exact method of encoding is discussed in section , but it's really only important to note the data is distributed uniformly across the entire CD, and each channel can hold a total of about 4MB. The P subcode channel identifies the start of a track, but is usually ignored in favor of the Q channel.
The Q subcode channel includes useful information, which can be read and written on many recorders. Other forms are found in the lead-in, and are used to enable multisession and describe the disc TOC table of contents.
This can be controlled when doing Disc-At-Once recording. It states the country of origin, owner, year of issue, and serial number of tracks, and may be different for each track.
It's optional; many CDs don't use this. The media catalog number is similar, but is constant per disc. Note these are different from the UPC codes. It enables properly equipped players to display text and graphics on Red Book audio discs. The most recent result of this technology is "CD-Text", which provides a way to embed disc and track data on a standard audio CD.
Subject: [] Are the CD Identifier fields widely used? Programs that identify audio CDs automatically don't rely on an embedded serial number. Subject: [] How long does it take to burn a CD-R? Burning MB of data takes about 74 minutes at 1x, 37 minutes at 2x, and 19 minutes at 4x, but you have to add a minute or two for "finalizing" the disc.
If you have half the data, it will finish in about half the time. If you record the same thing twice as fast, it will finish in about half the time. Most CD recording speeds are linear, i. If the drive uses a PCAV mechanism see section the speed varies depending on which part of the disc you're recording. If a "20x" drive uses PCAV to get 12x at the start of the disc and 20x near the outside, you know that burning 60 minutes of audio will take somewhere between about 5 minutes and about 3 minutes.
Subject: [] What's the difference between disc-at-once and track-at-once? The entire burn must complete without interruption, and no further information may be added. Track-at-once TAO allows the writes to be done in multiple passes. There is a minimum track length of blocks K for typical data CDs , and a maximum of 99 tracks per disc, as well as a slight additional overhead associated with stopping and restarting the laser. Because the laser is turned off and on for every track, the recorder leaves a couple of blocks between tracks, called run-out and run-in blocks.
If done correctly, the blocks will be silent and usually unnoticeable. CDs with tracks that run together will have a barely noticeable "hiccup". Some combinations of software and hardware may leave junk in the gap, resulting in a slight but annoying click between tracks. This gives you disc-at-once control over the gaps between tracks, but allows you to leave the disc open. This can be handy when writing CD Extra discs see section There are some cases where disc-at-once recording is required.
For example, it may be difficult or impossible to make identical backup copies of some kinds of discs without using disc-at-once mode e.
Also, some CD mastering plants may not accept discs recorded in track-at-once mode, because the gaps between tracks will show up as uncorrectable errors. The bottom line is that disc-at-once recording gives you more control over disc creation, especially for audio CDs, but isn't always appropriate or necessary.
It's a good idea to get a recorder that supports both disc-at-once and track-at-once recording. Subject: [] Differences between recording from an image and on-the-fly? Each method has its advantages.
These are complete copies of the data as it will appear on the CD, and so require that you have enough hard drive space to hold the complete CD. If you have both audio and data tracks on your CD, there would be an ISO filesystem image for the data track and one or more bit On the Mac, you might instead use an HFS filesystem for the data track. You can create the image with Mac CD recording software, or create it as a DiskCopy image file and then burn the data fork under a different OS.
On-the-fly recording often uses a "virtual image", in which the complete set of files is examined and laid out, but only the file characteristics are stored, not the data. The contents of the files are read while the CD is being written. This method requires less available hard drive space and may save time, but increases the risk of buffer underruns see With most software this also gives greater flexibility, since it's easier to add, remove, and shuffle files in a virtual image than a physical one.
A CD created from an image file would be identical to one created with on-the-fly recording, assuming that both would put the same files in the same places. The choice of which to use depends on user preference and hardware capability. Subject: [] How does an audio CD player know to skip data tracks? Set to allow copies, clear to prevent them.
Four-Channel Audio The Red Book standard allows four-channel audio, though very few discs have ever been made that use it. Pre-Emphasis Set if the audio was recorded with pre-emphasis. The last two are rarely used. It used to be called CD-Erasable CD-E , but some marketing folks changed it so it wouldn't sound like your important data gets erased on a whim.
Other than that, they are used just like CD-R discs. Let me emphasize that: they are used just like CD-R discs. Some software may handle CD-RW in a slightly different way, because you can do things like erase individual files, but the recorder technology is nearly identical. CD-RW drives use phase-change technology. Instead of creating "bubbles" and deformations in the recording dye layer, the state of material in the recording layer changes from crystalline to amorphous form.
The different states have different refractive indices, and so can be optically distinguished. Some Internet sites like to put the devices in completely separate categories, calling them "CD recorders" and "CD ReWriters", but the differences between them don't really merit such a distinction.
There is a limit to the number of times an area of the disc can be rewritten, but that number is relatively high the Orange Book requires , but some manufacturers have claimed as much as , Of course, this is under laboratory conditions. If you don't handle the disc carefully, you will add scratches, dirt, fingerprints, and other obstacles that make the disc harder for the drive to read. It appears that CD-RW discs have speed ratings encoded on them, so discs that are only certified for 2x recording can't be written to at 4x or, for that matter, 1x.
To make things more complicated, different media is required for high-speed CD-RW drives those that exceed 4x. If you're trying to decide if you want a drive that supports CD-RW, see section CD-R was designed to be read by an infrared nm laser.
DVD uses a visible red nm or nm laser, which aren't reflected sufficiently by the organic dye polymers used in CD-R media.
If the box doesn't say that something is supported, assume that the feature isn't. With recent cost reductions to DVD hardware, there's no real reason to buy a drive that only handles CDs or only handles DVDs and in fact they're increasingly difficult to find.
CDs are quickly surpassing the venerable 3. These days it's hard to buy a computer that doesn't support all formats. DVD-R recorders and media were initially very expensive, but eventually came down to consumer levels.
An example: electroweb. Subject: [] What are "jitter" and "jitter correction"? The other form of "jitter" is used in the context of digital audio extraction from CDs. CCleaner is a freeware system optimization, privacy and cleaning tool. CCleaner is the number-one tool for cleaning your Windows PC. Keep your privacy online and offline, and make your computer faster and more secure.
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Security updates for Acrobat, InDesign and more. Microsoft Edge browser version Intel driver update The best free SSD tools. These directories take precedence over all other ordering rules that are used for this image.
General image creation options can be used together with a single-boot entry option or multi-boot entry options to create bootable CD or DVD images. For more information, see Boot Options and Examples. Overrides the default maximum size of an image.
The default value is a minute CD. However, if UDF is used, the default has no maximum size. Specifies the timestamp for all files and directories. You can use any delimiter between the items. When you do this, note the following:.
For images larger than 4. Skip to main content. This browser is no longer supported. Download Microsoft Edge More info. Contents Exit focus mode. Please rate your experience Yes No. Any additional feedback?
Important Single-boot entries and multi-boot entries cannot be combined in the same command. In this article. Permits lower case file names. Does not force lowercase file names to upper case. Creates sparse files, when available, to make disk space usage more efficient. Specifies long allocation descriptors instead of short allocation descriptors.
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