Extron electronics VNM EC 200, Руководство пользователя, Страница: 85 / 242

Video Compression panel (see
figure 54
on the previous page)
1
Transform — Two transform types are supported.
•
graphics — Optimizes the video to support text and sharp lines, such as are
present on most computer screens.
•
video — Optimizes the video to support smooth tone changes, such as are
present in movies and other video content.
2
Luma Compression — This drop-down list sets the amount of compression on the
luma (black and white) portion of the signal. A value of 1 is the minimum amount of
compression available; a value of 10 is maximum compression.
3
Chroma Compression — This drop-down list sets the amount of compression on the
chroma (color) portion of the signal. A value of 1 is the minimum amount of compression
available; a value of 10 is maximum compression.
NOTE: This field is available only when the Luma/Chroma Lock is not selected.
4
Luma/Chroma Lock — Selecting this box disables the Chroma Compression
field and automatically sets chroma compression two levels higher than
Luma Compression .
When selected, the Chroma Compression field tracks the Luma Compression field
by a fixed value of +1 (Luma Compression = 1) or +2 (Luma Compression > 1).
5
Temporal Compression — Selecting this check box causes areas of the screen
to refresh only when a change between frames is detected. Enabling temporal
compression can significantly reduce network bandwidth.
NOTE: For all normal operation, Temporal Compression should be enabled.
6
Refresh Rate — This field controls how frequently static parts of the screen are
updated when the Temporal Compression check box is selected. This is useful
when connecting new displays to a temporally encoded source and fills in gaps in the
data when using a lossy network transport (such as RTP). A value of
1 refreshes the
screen once a second; a value of 10 refreshes the screen once every ten seconds. A
value of 0 disables the refresh. Valid settings are 1 though 17 .
7
Threshold — This drop-down list controls the sensitivity of the temporal change
detection algorithm. A value of 0 means any screen changes will be sent. Increasing the
value increases the send threshold and reduces the network bandwidth. A setting of 0
is suitable for DVI computer generated sources. Sources with more noise or video-type
motion should use a setting between
1 and 4 . Camera sources should always use
values greater than 0 .
8
Chroma Threshold — This check box controls whether the temporal algorithm should
consider changes in the color (chrominance) of the image. Selecting this check box
provides better results when using digital simulation type sources. However, this can
increase the transmit bandwidth by up to 200%, so it should be disabled on bandwidth
sensitive systems.
NOTE: This option is normally not required for video or camera type sources.
9
Motion — This drop-down list is used to adjust motion compression. The value can
be set from 0 to 15 , where 0 is no additional motion compression and 15 is full motion
compression. When enabled, motion detected on the area of the screen is heavily
compressed. This reduces bandwidth when the eye cannot perceive significant detail
due to the motion. When motion stops, the video continues at the standard resolution,
preserving screen integrity.
VNM EC 200 • Device Configuration and Control 75