YC Waveform

The YC Waveform displays a graph showing the signal intensity in the video clip. The horizontal axis of the graph corresponds to the video image (from left to right) and the vertical axis is the signal intensity in units called IRE (named for the Institute of Radio Engineers).

The YC Waveform displays luminance information as a green waveform. Bright objects produce a waveform pattern (bright green areas) near the top of the graph; darker objects produce a waveform toward the bottom. For NTSC video in the United States, luminance levels should range from 7.5 to 100 IRE (sometimes referred to as the legal broadcast limit). Japan’s implementation of NTSC standards permits a luminance range from 0 to 100 IRE. Generally, luminance and chroma values should be about the same and distributed evenly across the 7.5 to 100 IRE range.

The YC Waveform also displays chrominance information as a blue waveform. The chrominance information is overlaid upon the luminance waveform.

You can specify whether the YC Waveform displays both luminance and chrominance information, or just luminance information. For a video on reading a waveform monitor, see www.adobe.com/go/vid0238.

YC Waveform with the chroma control enabled

A.: IRE units
B.: Luminance (green) waveform
C.: Chrominance (blue) waveform
D.: Range of signal components

The YC Waveform has the following controls:

Intensity: Adjusts the brightness of the waveform display. It does not affect the video output signal.
Setup (7.5 IRE): Displays a waveform that approximates the final analog video output signal. Deselecting this option displays the digital video information.
Chroma: Displays both chrominance in addition to luminance information. Deselecting this option displays only the luminance.