MPC Specification That Currently Affects Multimedia
The following sections describe those MPC standards that are still current or have had a significant impact on decisions made about current technology.
A Standard for Managing Compressed Data Multimedia technology requires large volumes of data, so data compression becomes an important concern. The CPU and/or the software on a PC must be able to handle compressed video and audio data according to a data compression standard called MPEG, which is part of the MPC specifications. MPEG is an international standard for data compression for motion pictures. Developed by the Moving Pictures Experts Group (MPEG), it tracks movement from one frame to the next, and only stores what changes, rather than compressing individual frames. MPEG is a type of lossy compression. Lossy compression methods work by dropping unnecessary data, hence the idea of the loss of data or “lossy” compression. MPEG compression can yield a compression ratio of 100:1 for full-motion video (30 frames per second, or 30 fps).
Compressing and later decompressing data is called CODEC
follow the Pin 1 rule: match the edge color on the cable to Pin 1 on both the adapter card and the drive.
Some CD-ROM drives come with an audio cord that attaches the interface card to a sound card, which then receives sound input directly from the CD-ROM. Attach the audio cord if you have a sound card. Don’t make the mistake of attaching a miniature power cord designed for a 3 ½ inch disk drive coming from the power supply to the audio input connector on the sound card. The connections appear to fit, but you will probably destroy the drive by doing so.
Some drives have a good connection, with one end of the ground cable attaching to the computer case. Follow the directions included with the drive.
Verify Power to the Drive
Check all connections, and turn on the power. Press the eject button on the front of the drive. If it works, then you know power is getting to the drive.
Install the Device Driver for DOS
To operate in a DOS environment, a CD-ROM drive needs a device driver that is loaded from the CONFIG.SYS file. The driver interfaces with the drive and with a real-mode program called the Microsoft CD-ROM extension for DOS (MSCDEX.EXE), which must be loaded from AUTOEXE.BAT. Both of these programs will come on a floppy disk with the CD-ROM drive. Run the installation program that is also on the disk. It copies the files to the hard drive and edits both the CONFIG.SYS and the AUTOEXEC.BAT files. Restart the computer so that the changes will take effect. If there are problems accessing the drive after you have restarted, check the items listed under “Troubleshooting Guidelines”.
Install the Device Driver for Window 9x
Window9x supports CD-ROM drives without add-on drivers. Click Start, Setting, Control Panel, and double-clickAdd New Hardware. Click Next when you are prompted, “To begin