DVDO AVLab TPG, User Manual

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DVDO AVLab TPG - 4K Test Pattern Generator
DVDO AVLab TPG 21 A.04
Test Pattern Explanations
AVLab TPG has three types of test patterns:
• Visual patterns which can be used to roughly set display parameters and check performance and
calibration.
e.g. Frame and Geometry, Brightness, Contrast, focus, color bars, grey ramp etc.
•
Metering patterns that can be used with a simple meter to read and adjust colorimetry
e.g. solid primary, secondary and grey colors
•
Dynamically generated patterns
e.g. when connected to a software package, AVLab can create any color and window size
This is an explanation and how to use the visual patterns.
Frame & Geometry
This test pattern contains two specific test features. The first is a 1-pixel wide box around the very outside
of the image. This is used to determine when the entire iScan output image is visible on the display. The
arrows along the middle of each edge provide an indication of the amount of overscan (if any). The blue
boxes in the center of each quadrant are used for measuring display geometry. The rectangle in the
center of the gray boxes should appear square on a 4:3 aspect ratio display, the next large rectangle
should appear square on a 16:9 display, the next on a 1.85:1 display, and the largest rectangle should be
square on a 2.35:1 display. The blue boxes are also used as an indication that the horizontal positioning
of the output image is correct. This is particularly useful to align a video projector and also to visually
verify that a TV is not in overscan mode. If the blue boxes are displayed as red instead of blue, then the
Cb & Cr components are reversed. This can be corrected by ensuring that there is an even number of
pixels in the sum of the horizontal sync and horizontal back porch.