Pluge Test Pattern
PLUGE stands for Picture Line-Up Generation Equipment. A "pluge pattern" is a test pattern used to calibrate the black level on a video monitor. Black level basically refers to the brightness of the darkest areas in the picture (black is never completely black, it's just a very dark gray). Pluge patterns are usually generated by specialised video calibration equipment such as a synch pulse generator.
There are many types of pluge patterns but they all contain a variety of of black, white and/or gray shaded areas.
The example above includes three vertical bars and three shaded boxes. These areas are called pluge pulses. When the monitor is calibrated correctly:
- The first vertical bar (on the left) is black and can't be seen against the background
- The second vertical bar is only just visible as a dark gray.
- The third vertical bar is a lighter gray and clearly visible.
- The white box is a comfortable level of true white.
- There is no colour in the pluge display at all.