RGB Spectrum Digital Recording and Streaming System DGy 201x Benutzerhandbuch

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350-9047 v3.0.1
DGy Model 201x User’s Guide
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Threshold - When edge differences between blocks in 
successive frames exceeds the threshold value, a change is 
registered. The threshold value may be set to a number 
between 0 and 255 with a default of 16. A low threshold number 
requires small edge differences between blocks to be 
considered a change; a high threshold number allows greater 
differences before a change is indicated.
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Example
: A black foreground airplane against a blue and 
white sky can use a high threshold of 240. This threshold 
allows the DGy to locate only edges associated with the 
airplane while ignoring edges between sky and clouds. The 
threshold parameter would have to be lowered, possibly to 
50, if edges of a light gray airplane needed to be located 
against a medium gray cloud background.
Interframe Length - The interframe length establishes a 
minimum rate for the transmission of a new anchor frame 
regardless of the threshold or sensitivity setting. This insures 
that even slow, incremental changes are captured. Interframe 
length may be set to a value between 0 and 4095 with a default 
of 30. Interframe length should be adjusted after threshold and 
sensitivity parameters have been set.
To calculate the refresh rate:
Signal frame rate         
= Refresh rate in Hz
Interframe length 
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Example 1
: For a frame rate of 15 fps and an interframe length 
of 5, the minimum frame update rate would be:
 15  
= 3
 
Hz or 3 frames per second.
   5 
 
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Example 2
: For a frame rate of 30 fps and an interframe length 
of 59 the minimum update rate would be:
 30  
=
 1   
Hz or once every 2 seconds.
 60 
 2
The optimal interframe compression settings for an input depend on the 
nature of the image; some experimentation may be required. Set 
interframe compression values low for an image with a high degree of 
motion; this will keep the motion smooth. Higher settings may be used 
for an image with little motion. The higher the interframe length, the 
greater the reduction of network bandwidth used.