Nx Witness 5.0 introduced a new feature called Advanced Object Search. It allows the user to search for a specific object by using the object type and the attributes (metadata). While a camera detects an object, the camera will send the detected result to Nx Witness along with the extra information. Nx Server will store the objects and metadata in the Object Detection Database. Afterward, then the user can search them with simple keywords later (e.g. a car in white, a person with a face mask, or a man in a black suit, etc.).
By default, Nx Server saves the Object Detection Database to the computer’s OS drive. This is not an issue for Nx Servers that only records footage normally and with minimal or no object detecting applications. However, Nx Servers that have multiple object detecting applications running and creating many object detections (e.g. 100 objects per second) will begin to have longer than average response times during operations. You may experience that when searching for object detection events, it takes some time before the result appears.
In this case, you may consider saving the Object Detection Database on a dedicated drive (preferably an SSD) separate from the OS to offload and reduce the amount read/write tasks of the object detection database from the OS disk, and maintain the overall system performance as well as the speed of Object Advanced Search.
Move the Object Detection Database to a dedicated drive
Skip this section if you are installing the SSD on a newly installed Nx Server.
- Install an SSD on your device, then boot up the device.
- Stop the recording on all cameras.
- Stop Nx Server from running.
- Backup and move/copy the following files to the newly installed SSD:
C:\HD Witness Media\<server UUID>\archiveMove/copy to:
C:\HD Witness Media\<server UUID>\object_detection.sqlite
<SSD>:\HD Witness Media\<server UUID>\archive
<SSD>:\HD Witness Media\<server UUID>\object_detection.sqlite
<SSD mount path>/<server UUID>/archive
<SSD mount path>/<server UUID>/object_detection.sqlite
- Start Nx Server, then continue on to the next section.
Set Up the dedicated drive for Saving the Object Detection Database
- Install the SSD on your device, then boot up the device.
Note: Skip this step if you followed the previous section.
- Open Nx Desktop and connect to your Nx System.
- Right-click on the server and select Server Settings.
- Click on the Storage Management tab.
- Click Stores analytics data (the option will appear when hovering the cursor at the relative place of each storage location).
- Toggle the switch to disable recording on the SSD.
- Click the Delete or Keep button.
- Click the Apply button to save the settings.
If you have any questions related to this topic, or you want to share your experience with other community members or our team, please visit and engage in our support community or reach out to your local reseller.