Appendix E: Glossary 333
IEEE-1394: Developed by Apple Computers and
introduced as FireWire, this is a serial data
transmission protocol with rates up to 400 Mbits/sec.
Sony offers a slightly modified version for transmitting
DV signals named i.LINK, providing transmission
speeds up to 100 Mbits/sec.
Image: An image is a reproduction, or picture of
something. The term is often applied to digitized
pictures, consisting of pixels, that can be shown on a
computer display and manipulated by software.
Image compression: Method of reducing the amount
of data required to store digital image and video files.
Interlaced: The screen refresh method used by
television systems. The PAL TV image consists of
two interleaved image halves ( fields) of 312½ lines
each. The NTSC TV image consists of two image
halves of 242½ lines each. The fields are displayed
alternately to produce a blended image.
Interleave: An arrangement of audio and video to
promote smoother playback and synchronization or
compression. The standard AVI format equally
spaces audio and video.
I/O: Input/Output.
IRQ: “Interrupt Request”. An “interrupt” is a
temporary break in the main processing stream of a
computer so that housekeeping or background tasks can
be performed. Interrupts can be requested by either
hardware (e.g. keyboard, mouse) or software.
JPEG: Joint Photographic Experts Group, and the
standard developed by them for compressing digital
frames based on DCT.
