Digital Video Recorder User Manual 
 
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Step 6 On the Event Playback interface, you can select the main stream or sub-stream from the 
dropdown list for playback.   
The toolbar in the bottom part of Playback interface can be used to control playing process. 
 
Figure 6-8 Interface of Playback by Event 
Pre-play and post-play can be configured for the playback of event triggered record files. 
Pre-play: The time you set to play back before the event. For example, when an alarm triggered 
the recording at 10:00, if you set the pre-play time as 5 seconds, the video plays back from 9:59:55. 
Post-play: The time you set to play back after the event. For example, when an alarm triggered the 
recording ends at 11:00, if you set the post-play time as 5 seconds, the video plays back till 
11:00:05. 
Step 7 You can click    or    button to select the previous or next event. Please refer to Table 
6-1 for the description of buttons on the toolbar.   
6.1.4  Playing Back by Tag 
Purpose 
Video tag allows you to record related information like people and location of a certain time point 
during playback. You are also allowed to use video tag(s) to search for record files and position 
time point. 
Before playing back by tag 
Step 1 Enter Playback interface. 
Menu>Playback 
Step 2 Search and play back the record file(s). Refer to Chapter 6.1.2 Playing Back by Normal 
Search for the detailed information about searching and playback of the record files.