Ross Vision - Offsets

Vision Operator’s Manual (v12.0 MD) Appendix B: Color Correction Parameters • Ops 19–9
Figure 19.10 General Effects of Increased and Decreased RGB Gain (Red Component)
Generally, increasing the gain for a specific color component causes the video signal colors to
become increasingly saturated with that color. Similarly, decreasing the gain for a specific color
component progressively removes that color component from the output video signal.
Offsets
Offsets shift the video signal by a set amount. Depending on the offset applied, different parts of
the video signal may be affected. Clipping occurs if applied offsets cause output signal values to
fall outside the allowable range. The following graph (Figure 19.11) illustrates the general effect
of adding positive or negative offsets.
Figure 19.11 General Effects of Increased and Decreased Offset (Red Component)
The dashed line represents an upper offset applied to the B section of the video signal. The full
offset is applied to the B end of the video signal and decreases down to no offset being applied at
the A end of the video signal.
The dotted line represents a lower offset applied to the A section of the video signal. The full
offset is applied to the A end of the video signal and decreases down to no offset being applied at
the B end of the video signal.
The Vision switcher can perform upper and lower offsets on each RGB component:
• Offset — Shifts the selected color component (R, G, or B) of the video signal by a set
amount. The offset affects how much, if any, of the input video color component is
mapped to 100% of that color and how much, if any, is mapped to 0% in the output
signal. Increasing the offset increases the amount of input signal values that will be
mapped to 100% and decrease the amount of input signal values that will be mapped to
0% in the output signal. Decreasing the offset decreases the amount of input video signal
that will be mapped to 100% and increases the amount of input video signal that will be
mapped to 0% in the output signal. It is possible to increase the offset so no part of the
output signal contains 100% of the color component or decrease the offset so no part of
Red Input Value
Red Output Value
Standard
Increased Gain
Decreased Gain
A
B
100%
100%
0
Red Input Value
Red Output Value
Standard
Lower Offset (+ and - shown)
Upper Offset (+ and - shown)
A
B
100%
100%
0