Dahua Smart Box Series User Manual page 202

Standalone DVR User's Manual
Figure 4-81
4.11.1.3.2 Snapshot
Here you can set snapshot mode, picture size, quality and frequency. See Figure 4-82.
Snapshot mode: There are two modes: regular and trigger. If you set timing mode,
you need to set snapshot frequency. If you set trigger snapshot, you need to set
snapshot activation operation.
Image size: Here you can set snapshot picture size.
Image quality: Here you can set snapshot quality. The value ranges from 1 to 6.
Interval: It is for you to set timing (schedule) snapshot interval.
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