Picture line-up generation equipment
For televisions the picture line-up generation equipment is a greyscale test pattern used in order to adjust the black level and contrast of the picture monitor. Various PLUGE patterns can be generated, the most common consisting of three vertical bars of super-black, normal black, and near-black and two rectangles of mid-gray and white. These three PLUGE pulses are included in the SMPTE color bars used for NTSC, PAL, and SÉCAM.