Shotcut provides a video waveform scope to aid in setting video levels.
See Video Scopes for general information about video scopes.
The waveform scope displays graticules for 100 and 0 IRE. These graticules are hard fixed to a Y value of 16 = 0 IRE and a Y value of 235 = 100 IRE. These assignments are not user configurable.
While IRE is technically an analog video construct, it is included in this scope as a familiar and useful indicator for video levels.