Soyo STH-DCAM User Manual

STH-DCAM U

SER

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S 

M

ANUAL

 

 

 

 

 

 

 

 

 

 

 

 

 

2001 V

IDERE 

D

ESIGN

 

Both imagers are treated in exactly the same manner.  It is not possible to 
set a different exposure or gain on each imager. 

 

Digitization control can operate in either manual or automatic mode.  Refer 
to Figure 6-1 for the controls in the video capture program.   

In manual mode, the user program sets the exposure and gain.  The 
exposure and gain are based on a 0 to 100 scale.  Here are some tips for 
setting exposure and gain. 

•  In general, keep the gain as low as possible, since it introduces 

additional noise into the system.  Use it only if the exposure is set 
to maximum, or if the exposure must be kept low to minimize 
motion blur. 

•  Adjust the manual iris of the lens to as small an opening as 

possible for your application, without having to use gain.  This 
will increase the depth of field and give better optical performance.  

In many applications it is not necessary to work with the the full 640x320 
pixel array.  The CCD image processors are capable of reducing the amount 
of information contained in the digital video stream sent back to the host.  
They do this  by averaging the values from neighboring pixels, giving a 
higher signal-to-noise ration.  This technique is called binning.  Binning 
occurs automatically when a smaller frame size is selected. 

Figure 6-2 shows the frame size control on the video capture application.  
The two frame sizes allowed are 640x480 (full frame) and 320x240 (x2 
binning). 

The STH-DCAMs do not support subwindowing.. 

 

Frame rates from the STH-DCAM depend on the frame size and color 
mode.  Frame rates can be set under program control with the SetRate() 
function; see the Small Vision System User’s Manual.  For the smallv 
and smallvcap applications, frame rates are set at 30 Hz. 

  

320x240 

30, 15, 7.5 

30, 15, 7.5 

640x480 

30, 15, 7.5  

30, 15, 7.5 

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