DVDO AVLab TPG, User Manual

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DVDO AVLab TPG - 4K Test Pattern Generator
DVDO AVLab TPG 24 A.04
The ‘Horizontal Lines’ test pattern should appear as one pixel tall black and white rows. If you see any
irregular pattern(s) in the image then you know that the display is scaling the signal vertically.
Judder (Frame Rate)
The Frame Rate Conversion test pattern consists of a vertical bar which moves slowly back and forth
across the screen. The bar’s motion is updated once in each output frame period of the AVLab, and it
moves a fixed number of pixels horizontally in each frame period. This moving bar test pattern is intended
to identify the frame rates at which a display will operate. If the display is not performing any frame rate
conversion, i.e., it is actually displaying the output frame rate of the AVLab – the motion will be very
smooth. However, if the display is performing any type of frame rate conversion there will be very
noticeable stutter introduced in the smooth motion. There may also be other objectionable artifacts
introduced depending on how the display actually performs the conversion. These include tearing (top and
bottom portion of the bar are horizontally misaligned) and distortion.
PLUGE patterns (2 white and 2 black)
These patterns are used to visually adjust brightness (black level) and contrast (white level) as well as to
verify the display is in the correct color space mode.
RGB video is normally sent using all 256 bits (in 8 bit color) but YCbCr (component video) sets black at 16
and white at 238. This allows room above and below the active video for below black and above white.
PLUGE patterns are specifically designed to allow quick visual setting of the black and white level.
Using the black patterns (background is 16) so set the brightness level on the TV until you can just see
the difference between 16 and 17. Depending on how fine the display adjustment is, you may not be able
to get this exact, but 16 should be black and 17 grey. Everything below 16 should not be distinguishable.
Having this setting correct will bring out the details in dark pictures.