Apple Final Cut Pro 7 - Manual (Page 1320)

• Clamp Above: All luma values above this parameter value are clamped to the parameter
value. The lower you set this value, the more clipping occurs at the top of the waveform.
• Max. Output: Compresses the range of values between the Start (Threshold) and Clamp
Above values so the maximum output value is the value set here. Setting this value
higher than the Clamp Above value has no effect. Values below the Start (Threshold)
value clip the signal.
• Start (Threshold): Defines the lowest value affected by the Custom Luminance Limiting
controls.
Custom Saturation Limiting Controls
• Enable: Select or deselect the checkbox to turn on or turn off the Custom Saturation
Limiting controls.
Note: You can still adjust the sliders below, but they have an effect only when this
checkbox is selected.
• Clamp Above: All chroma values above this parameter value are clamped to the
parameter value. The lower you set this value, the more clipping occurs.
• Max. Output: Compresses the range of values between the Start (Threshold) and Clamp
Above values so the maximum output value is the value set here. Setting this value
higher than the Clamp Above value has no effect. Values below the Start (Threshold)
value clip the signal.
• Start (Threshold): Defines the lowest value affected by the Custom Saturation Limiting
controls.
• Reduce Chroma/Luma: When the combination of the luma and chroma signals is too
high and the Broadcast Safe filter can reduce either luma or chroma to make the
combined signal legal, this parameter determines how much luma and chroma are
reduced. When the slider is set to 100 (centered), the filter reduces luma and chroma
equally.
Note: The Custom Luminance Limiting and Custom Saturation Limiting controls are
effective only when you choose Custom from the Luma/Chroma Mode pop-up menu.
RGB Limiting Controls
• Enable: Select or deselect the checkbox to turn on or turn off the Max. RGB Output
Level parameter. When this parameter is enabled, any equivalent RGB values that
exceed the Max. RGB Output Level parameter value are clamped to that value. Negative
RGB values are automatically clamped to zero.
Note: Unlike the Custom Luminance Limiting and Custom Saturation Limiting controls,
this option can always be enabled, regardless of the option currently selected in the
Luma/Chroma Mode pop-up menu.
• Max. RGB Output Level: This parameter value is the maximum RGB-equivalent value
that the filter outputs.
1320 Chapter 78 Measuring and Setting Video Levels