Appendix D
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Glossary of Terms
displayed at a rate of 25 frames per second. PAL is based on a
625/50-line/field system. The bandwidth for PAL is 5.5 MHz
for luminance and 1.3 MHZ for U and V. Other standards are
NTSC and SECAM.
PCI –
Refers to Peripheral; Component Interconnect, a high-
speed-system bus specification that provides 32 or 64-bit data
paths at 33 or 66MHz clock rates.
Pixel
– Refers to a single element of an image.
Post-filtering
– Processing pictures after compressing, i.e.
scaling to size and smoothing edges.
Pre-filtering
– Processing pictures before compressing, i.e.
scaling to size and smoothing edges.
P Frame
– Predicted frame; used in MPEG compression, which
are coded with respect to the nearest previous I or P frames. P
frames serve as a prediction reference for B-Frames and future
P frames.
Processing
– Refer to Encoding.
QSIF
– Refers to Quarter Standard Interface Format. The
computer industry, which uses square pixels, has defined QSIF
to be 160
×
120 active pixels, with a refresh rate of whatever the
system is capable of supporting.
Red Book
– Formal standards document for CD Digital Audio.
RS-232 –
A standard defined by EIA specifying the electrical
characteristics of slow-speed interconnections between
terminals and computers or between two computers. Although
the standard commonly used is RS-232C, most people refer to it
as RS-232.
Saturation
–
Defines the intensity of color. A color with a high
saturation appears very strong. A color with low saturation
appears washed-out. Zero saturation is white (no color), and
maximum saturation is the deepest color possible.
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