PRISM MPI2-25 and MPX2-25 Media Analysis Platform User Manual
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Line Select.
Line Select allows you to choose the picture lines to monitor in the
display. Either
All Lines
or
1 Line
can be selected.
If
1 Line
is selected then the display will only show results for the selected line in
the picture. The line can be selected using the on-screen tools.
(See Line Select
function.)
Or the line can be selected directly on the Picture. (See Figure 207.)
Checking gamut
The Diamond display effectively shows how the R, G, and B signals relate. The
Diamond display is a good tool for detecting gamut errors.
To form the Diamond display, the instrument converts the Y, P
b,
and P
r
components
recovered from the serial signal to R, G, and B. To predictably display all three
components, they must lie between peak white, 700 mV, and black, 0 V.
For a signal to be in gamut, all signal vectors must lie within the G-B and G-R
diamonds. Conversely, if a signal vector extends outside the diamond, it is out of
gamut. The direction of an excursion out of gamut indicates which signal is
excessive. Errors in green amplitude affect both diamonds equally, while blue
amplitude errors affect only the top diamond and red errors affect only the bottom
diamond. (See
Figure 205
.)
Figure 205: Diamond display plot
Compare the signal to the display to determine out-of-gamut components. Be
aware of these details:
•
The intensity of a vector indicates its duration.
•
A momentary out-of-gamut condition appears as a faint trace. Long
duration violations show as a bright trace.
