Signal Capture
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VGA Grid User Guide
image’s position. For example, a captured image that
is shifted slightly to the right or horizontally can be
corrected with minor adjustments to the horizontal
shift settings.
Increasing or decreasing the value entered in the
Horizontal Shift field shifts the image to the right or
left.
Phase
Configuring the phase, or sampling phase as it is also
known, adjusts the horizontal resolution of the
image. An improperly adjusted phase will result in a
fuzzy image. Adjust the sampling phase in small steps
until a sharper image is displayed.
PLL adjustment
Configuring the PLL adjusts the vertical
synchronization properties of the image. The PLL
adjustment may need to be changed when there is a
repetitive distortion or blurriness on the horizontal
axis of the image. Adjust the PLL setting in small steps
until a sharper image is displayed.
Offset
Use the offset and gain controls together to optimize
image quality. Increasing the offset reduces
background noise but also reduces the overall signal.
Balance offset and gain values to achieve the best
quality image. Adjust these settings by the smallest
values possible to achieve the best results.
Compensate for a large change to one by making a
large change to the other, but setting both offset and
gain to high values can result in poorer video quality.
Gain
Use the offset and gain controls together to optimize
image quality. Increasing the gain amplifies weak
signals but also increases noise. Balance offset and
gain values to achieve the best quality image. Adjust
these settings by the smallest values possible to
achieve the best results. Compensate for a large
change to one by making a large change to the other,
but setting both offset and gain to high values can
result in poorer video quality.
Aspect ratio
Sets the aspect ratio of the captured image. The
default aspect ratio is 4:3. The aspect ratio can be set
to wide mode in order that the VGA Grid can
accurately capture wide aspect ratio modes.
HSync threshold
Adjusts horizontal sync detection
