multiplied (for example, a block of four equally colored pixels represents the original pixel), aliasing effects (“blocks” and “stairs”) will occur. This can be avoided by interpolation procedures (using average colors for inserted pixels). Horizontal interpolation (x filter) is relatively easy to perform, since the pixels are drawn to the screen in lines. Vertical interpolation (y filter) is more difficult and requires a complete pixel line to be buffered.
I/O Address/Port
Input/Output addresses or I/O addresses are physical addresses of hardware subsystems such as those for interface cards or parallel ports. The parallel port and the serial port(s) both use an I/O setting which is configured in the BIOS.
IRQ
Interrupt ReQuest lines are hardware connections which can transmit interrupt signals from hardware subsystems to the CPU to trigger certain procedures. The parallel port and the serial port(s) both use an IRQ setting which is configured in the BIOS.
ISIS
Image and Scanner Interface Standard. A scanning standard developed by Pixel Translations. None of the Info ImageReader scanners have ISIS drivers. ISIS is used primarily in scanners which a solely dedicated to imaging for OCR purposes.
ISP
Internet Service Provider, these organizations or businesses allow individuals to log on to their computers for the purpose of connecting to the Internet. There are primarily four types of ISPs. The direct connection to the Internet allows the use of your own Internet software but will often provide basic Internet software (i.e. a Web Browser and Email client) for free. The commercial online service, such as America Online (AOL) or CompuServe, requires you to use a specific type of software (proprietary) to connect to their service and browse the web or read and send email. Many colleges and universities allow their students and faculty to connect to various parts of the Internet for such things as email and web browsing. And, there are several companies that allow an individual to access email sending and receiving for free. These free email ventures often use a proprietary email client and/or restrict the email in some way, such as not allowing file attachments or allowing only a maximum number (or volume) of messages per day.
Laser Printer
A laser printer prints using a dry toner xerographic process which is the same process photocopiers use.
Line Art
Images that are purely black and white, such as black type writing on white paper or line drawings. Line Art is a
Lossy
When a file is compressed using JPG or another “lossy” format, to compress the file size some of the picture elements are excluded or lost. With most degrees of compression, the changes to the image are usually only apparent when you magnify the image. Using a lower compression rate (some applications will allow you to configure this) will produce less loss.
Luminance
The perceived brightness, black and white value, of a pixel in video.
Memory Manager
A program for handling memory above the 640 K barrier of DOS. DOS comes with its own memory
58