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Compact
Disc (CD) : Color Books
The entire CD technology family conforms to a set of international standards, commonly referred to as color books, to ensure all CDs are compatible with other CD players -ROM drives. Even though the basic construction of every CD is the same, their formats vary by use. RED BOOK defines a CD Audio standard for the common audio CDs you buy at the store.
The Red Book describes the physical properties of the compact disc and the digital audio encoding. It comprises:
The current status and versions of the Red Book and extensions are listed below.
The Red Book is also available as the international standard, ISO/IEC 60908, and is available in English and French from the International Electrotechnical Commission (IEC), http://www.iec.ch/. Yellow Book - CD-ROM & CD-ROM XA The Yellow Book comprises the CD-ROM specification plus an extension for CD-ROM XA. The Yellow Book for CD-ROM was written in 1984 to describe the extension of CD to store computer data. This specification comprises the following:
The current status and versions of the Yellow Book and associated CD-ROM XA specification are listed below.
The Yellow Book is also available as the international standard, ISO/IEC 10149, and is available in English from the International Electrotechnical Commission (IEC), http://www.iec.ch/. White Book - Video CD The White Book defines the Video CD specification and comprises:
The various Video CD formats and enhancements are listed in the table below.
Blue Book - Enhanced CD The Blue Book defines the Enhanced Music CD (also known as CD Extra) specification for multisession pressed disc (ie not recordable) comprising audio and data sessions. These discs are intended to be played on any CD audio player, on PCs and on future custom designed players. The Blue Book comprises:
Last updated: Version 1.0, Dec 1995 Photo CD Book Photo CD has been specified by Kodak and Philips based on the CD-i Bridge specification. It comprises the following:
Last updated: Dec 1994 Multisession CD specification for pressed discs is a Philips/Sony standard (actually yellow in colour) defining discs which have two or more sessions but are pressed not recordable. The only pressed multisession disc format currently defined is the Enhanced Music CD, defined in the Blue Book. The latest version of the Multisession CD book (Version 1.0, December 1995) defines the following:
Last updated: Dec 1995 Orange Book - CD-R and CD-RW The Orange Book defines CD-Recordable discs with multisession capability.
All three parts contain the following sections:
Contact Details for CD Books These Books are obtainable from: Philips Intellectual Property &
Standards, These books define the characteristics of the recorder and blank discs, and how to perform the recording. One of the unique features of a CD-ROM is its ISO9660 file system, sometimes called the logical format. ISO9660 defines the format in which files and folders are arranged on a CD-ROM so a computer can locate them. The system is cross-platform compatible, so that standard CD-ROMs can be read by PCs, Macintosh and even UNIX systems. Of course, application programs are designed for specific types of computer platforms, but the actual files and folders are visible under other platforms. Hybrid CD-ROM discs combine ISO9660 with another native file system, such as the Macintosh or UNIX operating systems. These discs contain native PC and native Macintosh (or UNIX) sections, and display only the files for the type of computer reading the disc. Today, CD-ROM discs are used to distribute software and information on a large scale. Since most PCs today have CD-ROM drives built in, distributing application programs and data is a snap. In the past, an application program that took 20 floppy disks to install can easily be placed on a single CD-ROM disc. The user simply starts the installation process and can walk away-no more swapping floppy disks! Because CD-ROM discs are inexpensive to produce, hold up to 650 MB of data and have wide compatibility with popular computer systems, they are ideal for distributing large amounts of data or applications to computer users. CD Recordable (CD-R) Technology Compact Disc Recordable technology was developed in the early 1990s as a tool for software developers who wanted to prototype discs before stamping thousands of them. The first CD recorders cost over $100,000 and were as big as washing machines. The blank discs cost more than $100. Today, an entry-level CD-R drive costs under $300, looks just like a CD-ROM drive and the blank CD-R discs cost only a few dollars. CD-R discs can hold up to 650MB of computer data, or up to 74 minutes of quality CD music. CD-R is a "write once" technology-once the data is recorded, it is permanent and cannot be changed or erased. The data from the computer is broken down into "1s" and "0s" and burned into the recording layer of the CD-R disc as dark spots. Data is read back from a CD-R disc just like a regular CD-ROM. However, CD-R discs look different than regular CDs. They are usually gold on the label side, while the other side might be green or gold, depending on the recording material. Once CD-R discs are recorded, they can be read by any standard CD-ROM drive or CD player, because the recorded disc "looks" the same as a stamped CD to the player. Data can be added to CD-R discs in "sessions", but not erased. CD-R Compatibility The ISO9660 file system is typically used to record a CD-ROM, in order to ensure compatibility with multiple CD-ROM drives and operating systems. However, a newer file system called Universal Disc Format (UDF), a more flexible and efficient format for recording CDs, is also becoming popular. ISO9660 was designed for read-only discs and is cross compatible, but not ideal for writing files and folders one at a time. Of course, the other popular format is CD audio, which is universal for playing audio discs in any CD player, CD-ROM or even DVD-ROM drive. CD-ReWritable (CD-RW) Technology Compact Disc ReWritable technology is a recent addition to the CD family and a natural extension of CD-Recordable technology. As its name suggests, a CD-RW disc can be erased and re-written, in the same way a floppy disk can be erased or re-formatted. Just like CD-R discs, CD-RW discs hold up to 650 MB of data or 74 minutes of CD quality music. CD-RW discs are silver on the label side, just like a stamped CD, however, the recording side is a dark gray color. CD-RW uses a technology called "phase change" to record a "mark" on the disc that simulates a pit. This is accomplished by heating the spot to be recorded to a specific temperature very quickly. The mark can be changed by heating the spot again to a lower temperature, causing it to re-crystallize. This cycle can happen about 1,000 times on current CD-RW media. CD-RW Compatibility While CD-RW discs can be erased and re-written, they cannot be read by all standard CD-ROM drives and CD players. The phase change recording material of a CD-RW disc isn't as reflective as a stamped disc or even a CD-R disc. As a result, the recorded CD-RW discs are only readable in CD-ROM drives that advertise CD-RW compatibility, or that conform to the new Multi-Read specification. While most new CD-ROM drives sold today are compatible with CD-RW discs, there are many drives already installed in computers that cannot read these discs. However, CD-RW discs were not designed to replace CD-R, in fact they are complementary technologies. A CD-ReWritable recorder is a multi-function drive. It can record a CD-RW or a CD-R disc. Since CD-RW discs cost more than CD-R discs, and are not as compatible with CD-ROM drives installed in the field, CD-R discs remain the best medium for distributing large files and data. CD-RW, because it is rewritable, is better for general data storage (personal file storage) or daily back ups, whenever data is frequently updated. CD-RW is also an ideal prototyping medium for making a CD-ROM that will eventually be stamped. If a problem is found in the program, a change can be made and the CD-RW disc re-burned with the new information. When the project is done, a CD-R disc can be recorded as a master. CD-R -RW work together to meet all your information management needs. CD-RW Recording Software The same CD recording software used to record a CD-R disc can be used to record a CD-RW disc. All the same disc formats apply to CD-RW. You can record music onto a CD-RW disc, however, you probably wouldn't be able to play it in your car or home stereo. For that application, use a CD-R disc in the recorder. Pre-mastering software that supports CD-RW discs usually has an option to erase or "blank" a CD-RW disc. This is necessary, as a CD-RW disc recorded with this type of software looks like a regular CD-ROM or CD Audio disc to the CD recorder once it has been written. Drive Letter Access software can directly overwrite a file with CD-RW media so you should never have to erase this kind of disc.
Q: Can I make my own music CDs with a CD-RW drive?
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