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
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.
Blanking Area |
Incorrect Active Area |
Active |
Lines |
Active Area |
Active Pixels
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
