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Multimedia Standard
Source: DPD, Clive Greenfield
Multimedia Standard - MPC 2
Minimum specification of a PC running multimedia software.
- 4MB 486SX PC running at 25 MHz with a 160MB hard drive.
Video card capable of 65536 colors on
standard 640x480 VGA display
- CD-ROM drive capable of 300KB/s and less
than 400ms average seek
Capable of reading XA (mixed data and audio tracks)
and multisession.
- 16-bit sound card capable of playing audio
at 44.11kHz, 22.05kHz and 11.02kHz mono and stereo
CD-DA Red Book 1983
The first standard, introduced for digital audio market. Defines the disk's basic structure: a single track running from center to edge and split into 2352 byte sectors with a specific data correction method.
CD-ROM Yellow Book
Created by Philips and Sony. Split into two standards:
Mode 1 for computer data. Each sector has 288 bytes of error correction.
Mode 2 for compressed audio and video data. This type of data would not normally need error correction.
ISO 9660 - High Sierra
A common filr structur format set-up in 1983 by major manufacturers allowing Mac, UNIX, DOS machines to access the saame CD-ROM data. After minor changes it was ratified by the ISO.
CD-ROM XA (eXtended Architecture)
Developed by Philips and Sony as an extension to the Yellow Book Mode 2. Also split into two standards, Mode 2 Form 1 and Mode 2 Form 2. A description of the sector type in the header allows the two forms to be interleaved on a sector by sector basis. The interleaving gives the impression that video and audio playback are in synch:
Mode 2 Form 1 designed for computer data.
Mode 2 Form 2 designed for compressed audio and video/picture data. Audio compression in this mode requires decompression hardware within the drive that makes it audible to the user.
CD-ROM XA Ready
Same as for XA but XA Ready players support Mode 2 Form 2 without audio compression.
CD-I Green Book
Developed by Philips for its CD interactive machines. These machines are not PC compatible but additions to the Green Book standard, such as CD-Bridge Disk allows XA disks (including Photo CD) to be played on XA CD-ROM players as well as CD-I machines. CD-ROM drives are now CD-I ready meaning they can read and decode the CD-I tracks but additional hardware is needed for post-processing the data.
CD-I Bridge
A special type of CD-ROM XA with a CD-I application program, that is cross-platform.
CD-I Ready
Specially formatted CD-DA disk that can be played on a standard CD-DA player and CD-I player and that gives additional information about the music content on the disk.
CD-R Orange Book
Developed for writeable CD-ROM systems that operate in a similar way to WORM drives.
Photo CD
A Kodak proprietary encoding scheme using the XA Mode 2, Form 1 disk format. Introduced the multisession disk. Each session has lead-in and lead-out sections that take some 18MB of space. Older CD-ROM drives can be upgraded to read Photo CD but are not necessarily multisession. Drives with Photo CD support do not necessarily imply full XA read capability.
AVI (Audio Video Interleave)
Microsoft's standard that is a compromise between the storage and the speed requirement of full motion video and the limited capacity (for video) of CD-ROM. Allows capture and CD-ROM playback of small (160x120 pixel) 256 color video at 15 frames per second, which is about half television speed.
DVI (Digital Video Interactive)
Intel and IBM technology that requires additional hardware, like IBM's Action-Media II adapter, to compress and decompress full-motion video. It can be mixed with still images and audio from a variety of sources.
Video CD (White Book)
A reproduction standard to present full motion video and associated audio. This is achieved by using interleaved video MPEG compression and audio MPEG compression. The Video CD format is based on CD-I Bridge disk format and as such can be played on CD-I, CD-ROM XA and Video CD players with the associated system hardware and software.
MPEG1 (Motion Picture Expert Group)
A digital compression/de-compression standard intended for full screen/full motion video and stereo audio playback. The combined video and audio data is played back from a CD-ROM drive at single speed (150KB/s). The picture rates are about 24 to 30 fps.
MPEG2
Provides for faster transfer rates and higher quality video and audio than MPEG1. Not defined when this document was written.
JPEG (Joint Pictures Expert Group)
Intended for the compression/de-compression of still images and has been adapted for video.
M-JPED (Motion-Joint Pictures Expert Group)
Here JPEG compressed images are played back at 30 fps. Audio is not compressed. Compression ratios depend on the transfer speed and storage capacity of a hard disk.
Clive Greenfield