Glossary
- A-Time:
- Absolute Time. Elapsed time, referenced to the program start (00:00:00),
on a CD or R-DAT. A-Time is measured in minutes, seconds, and frames.
- Authoring:
- Creation of a database for a CD-ROM. The end product of authoring is usually
a search and retrieval type document with the addition of a user interface.
Specific authoring functions include tagging and indexing.
- CD-I:
- Compact Disc Interactive. An interactive multimedia system which connects
to a television. The CD-I standard is known as the Green Book.
- CD-ROM/XA:
- CD-ROM Extended Architecture. A standard which allows interleaving of compressed
audio and video data for synchronization purposes.
- ECC/EDC:
- Error Correction Code/Error Detection Code. Codes specified in the color
book standards and imbedded in CD data which facilitate the reconstruction
of data if read errors occur.
- HFS:
- Hierarchical File System, used by the Macintosh platform. HFS formatted
CD-ROMs have the same file structure as an Apple hard disk.
- Hybrid Disc:
- A CD-ROM which can function on either the PC or the Macintosh platform.
The disc contains separate ISO 9660 and HFS partitions.
- Indexing:
- Creation of a data index to speed up search and retrieval.
- ISO 9660:
- An international standard defining the file and directory structures for
CD-ROM. An ISO 9660 formatted CD-ROM will function on any computer platform
containing the appropriate driver software. Most common with PC compatible
systems
- Media Conversion:
- The process of converting data from one type of media to another for premastering
and mastering. Premastering software typically requires input data on hard
disk. 8mm tape and compact disc are preferred as input media for the mastering
process.
- Mixed Mode Disc:
- A CD-ROM that contains both a computer data track (#1) and audio tracks
(#2-99)
- Mode 1:
- Most common CD-ROM data format. Contains three layers of error correction
for computer data.
- Mode 2:
- CD-ROM data format with two layers of data correction for audio and compressed
video. Utilized in CD-ROM/XA.
- PQ Information:
- Information on the disc (or tape) that determines track start points, control
bits, timing information, etc.
- Premastering:
- The process of formatting data into the exact image that will appear on
a CD-ROM, including file structure (i.e. ISO 9660) and file locations. A
premastered image is ready to be mastered and replicated.
- SMPTE Time:
- Time code adopted for use with the 3/4" U-matic tape used in CD Production.
Originally used for video, this was devised by the Society of Motion Picture
and Television Engineers.
- Tagging:
- Placing hidden markers in text to indicate where to insert specific images.
- Transfer Rate:
- The amount of data which is transferred from the CD-ROM to the computer.
The CD-ROM transfer rate is limited by the speed at which the disc rotates
in the drive. The conventional CD-ROM transfer rate is approximately 150
kilobytes/sec, referred to as 1x. Therefore, a quadruple speed (4x) CD-ROM
drive can transfer data at a rate of 600 KB/sec.
- Yellow Book:
- International standard which defines the physical properties of a CD-ROM
disc.
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