Active Pixels And Active Lines Status Indicator Bars - Extron electronics IN1508 User Manual

Operation, cont'd
Similarly, if the vertical start adjustment is set to less than the amount of actual
blanking, the IN1508 starts scaling before the first line of the active image. This
early scaling results in a blank border on the top and cropping on the bottom, and
looks as if the image is shifted down.
Adjust the H Start status indicator bar to shift the switcher's starting point
horizontally on the screen. Adjust the V Start status indicator bar to shift the
starting period vertically on the screen.
If improperly adjusted, the output position variable can result in an image similar
to figure 3-24. But, position only moves the image on the monitor. It does not add
blank borders or crop any part of the image. However, the apparent effect of blank
borders and a cropped image can be caused by the image being improperly
positioned on the monitor.

Active Pixels and Active Lines status indicator bars

Figure 3-25 shows an image whose active area is improperly set, as indicated by the
dashed lines. If the number of active image pixels that the switcher is set to scale
are less than the amount of actual active pixels that are input, the IN1508 only
scales the set active area and skips some of the input pixels. This early end to the
scaling process results in an output with fewer pixels than it should have, and looks
as if the image is stretched horizontally.
Active
Lines
Figure 3-25 — Incorrect active area setting
Similarly, if the number of active image lines that the IN1508 is set to scale is less
than the amount of actual active lines that are input, the IN1508 scales only the set
active area and skips some of the input lines. This early end to the scaling process
results in an output that has fewer lines than it should have, and looks as if the
image is stretched vertically.
Depending on the RGB source, the input sampling rates in the following table may
have the same horizontal scan rate and vertical refresh rate. The switcher does not
detect pixel space differences (you can have different numbers of pixels in the
same horizontal and vertical rates) between input rates. The switcher applies the
3-36 IN1508 Scaling Presentation Switcher • Operation
Blanking Area
Incorrect Active Area
Active Area
Active Pixels