Grass Valley Kalypso User Manual V.15.0 - Manual (Page 92)

92 Kalypso — User Manual
Section 2 — Concepts
When the DPM provides a shaped video output but the key is processed as
though it were unshaped, the shaped video does not completely fill the key
hole in the background so a dark halo appears around the key (
Figure 66 ).
Figure 66. Incorrect Key with Dark Halo
In this case the shaped input is incorrectly shaped again, sometimes called
a double-multiply (
Figure 67 ).
Figure 67. Incorrect Keying with Shaped Input
When the DPM provides an unshaped video output but the key is pro-
cessed as though it were shaped, excessive luminance occurs where the key
fill video and key hole edges overlap, producing a white halo around the
key (
Figure 68 ).
x
+ Invert
Background Key Hole in Background
Key Control
Shaping Circuit On
Doubly-Shaped
Video
Incorrect Key
with Dark Halo
0618_00_34
Shaped
Key Fill
x
Correct Key