Digital Video Recorder User Manual 
 
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You can click the checkbox of Save VCA Picture to save the captured pictures of VCA 
detection.   
Step 3 Select the VCA detection type to Audio Exception Detection. 
Step 4 Click    to configure the trigger channel, arming schedule and linkage action for the audio 
exception alarm.     
Step 5 Click the Rule Settings button to set the audio exception rules. 
 
Figure 10-10 Set Audio Exception Detection Rules 
1)  Check the checkbox of Audio Loss Exception to enable the audio loss detection function. 
2)  Check the checkbox of Sudden Increase of Sound Intensity Detection to detect the sound 
steep rise in the surveillance scene. You can set the detection sensitivity and threshold for 
sound steep rise. 
Sensitivity: Range [1-100], the smaller the value is, the more severe the change should be 
to trigger the detection.   
Sound Intensity Threshold: Range [1-100], it can filter the sound in the environment, the 
louder the environment sound, the higher the value should be. You can adjust it according 
to the real environment. 
3)  Check the checkbox of Sudden Decrease of Sound Intensity Detection to detect the sound 
steep drop in the surveillance scene. You can set the detection sensitivity [1-100] for 
sound steep drop. 
Step 6 Click Apply to activate the settings. 
10.14 Defocus Detection   
Purpose