Contrast And Brightness - Avocent SwitchView IP 1020 Guide D'installation Et D'utilisation

2. Click the icon corresponding to the feature you wish to adjust.
3. Move the Contrast slider bar and then fine-tune the setting by clicking the Min (-) or Max (+)
buttons to adjust the parameter for each icon pressed. The adjustments display immediately in
the Video Viewer window.
4. When finished, click Close to exit the Manual Video Adjust dialog box.
Image capture width, pixel sampling/fine adjust, image capture horizontal position
and image capture vertical position
The Image Capture Width, Pixel Sampling/Fine Adjust, Image Capture Horizontal Position and
Image Capture Vertical Position adjustments affect how the target video is captured and digitized
and are seldom changed.
The image capture parameters are automatically changed by the Automatic Adjustment function. A
special image is required on the target in order to make accurate adjustments independently.

Contrast and brightness

If the image in the Video Viewer window is too dark or too light, select Tools - Automatic Video
Adjust or click the Automatic Video Adjust button. This command is also available in the Video
Adjustments dialog box. In most cases, this corrects video problems.
In cases where clicking on Auto Adjust several times does not set the contrast and brightness as
desired, adjusting the contrast and brightness manually can help. Increase the brightness. Do not go
more than 10 increments before moving the contrast. Generally, the contrast should be moved
very little.
Detection thresholds
In some cases, noise in the video transmission keeps the packets/sec count up, which is indicated by
little dots changing in the area of the cursor when it is moved. Varying the threshold values may
result in "quieter" screens and can improve cursor tracking.
You can modify Noise Threshold and Priority Threshold values if you are using standard video
compression. You can also modify Block Noise Threshold and Pixel Noise Threshold values. You
can restore default threshold values by clicking Auto Adjust Video.
Block noise threshold and pixel noise threshold
The Block Noise Threshold and Pixel Noise Threshold values set the minimum color levels in
terms of changed video blocks and pixels per thousand that are allowed.
• The Block Noise Threshold sets the minimum color change that occurs in a single video block.
Increasing the value reduces the network bandwidth. Decreasing the value makes the size of
these artifacts smaller.
• The Pixel Noise Threshold sets the minimum color change in a single pixel. Decreasing the
value reduces the number of low-contrast artifacts, but increases network bandwidth.
Chapter 4: The Video Viewer
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