QNAP Security NVR-101 (Version: 2.8.0) - Manual (Page 39)

z Quad-view Playback
Quad-view playback allows you to find the video more quickly. You can check
the video of four different cameras or time periods simultaneously. NVR
provides the Express Quad View Playback for your convenience. You can
either divide the selected time equally into four playback views or load four
consecutive cameras to play.
Express Quad View Playback: Divide the selected time equally into
four playback views
Select only one camera, and check the option "Divide the selected time period
equally into all the playback windows to play". Click "OK".
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