Quantum Data 801GC - Manual (Page 93)

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SMPTE133
Description This image is based on a recommended practice
(RP-133) test pattern designed by the Society of
Motion Picture and Television Engineers (SMPTE).
The original application was used in testing and
evaluating medical imaging monochrome displays.
The image now is used in many different display
applications. The image is self scaling as to the
number of active pixels and active lines used. Some
of the image’s elements have minor differences
from the original SMPTE specification. These
d i f f e r e n c e s a r e n o t e d i n d e s c r i p t i o n s o f t h e
individual elements.
1) T h e i m a g e i s d r a w n o n a r e f e r e n c e
background having a 50% intensity level. The
background covers the entire active video
area.
2) Crosshatch – There are 10 boxes vertically.
The number of horizontal boxes is based on
the physical aspect ratio determined by the
HSIZ and VSIZ parameters in the currently
loaded format. The boxes are perfectly square
with any fractional spaces placed around the
outside edges of the image. The vertical lines
are two (2) pixels thick while the horizontal
lines are two (2) scan lines thick. Small crosses
indicate the intersection of the horizontal and
vertical lines when they are covered by other
parts of the image. All parts of the crosshatch
are normally drawn using a 70% intensity
level. A 75% level is used in the secondary
version.
3) Resolution Patch – The patch is made up of
six (6) smaller boxes that are each about 6.25%
of the height of the display. The boxes are
made of alternating intensity (0 and 100%)
s t r i p e s . T h e s t r i p e s r u n v e r t i c a l l y a n d
horizontally. The stripes may be one (1), two
(2) or three (3) pixels wide each. Details of
the patch are shown in the lower half of the