What is a Virtual Camera?
Creating a Virtual Camera makes it possible to import offline video files (from wearable cameras, action cams, drones, etc.) into the Nx Witness archive and associate that footage with a virtual camera which can be viewed and processed like any other camera in the System. (Note: the FPS and bitrate recording options are inactive.)
Note: To be processed as a virtual camera, a device must produce video file types that have contain EXIF data (EXIF is short for Exchangeable Image File).
Like camera streams recorded by Nx Witness, videos uploaded using the Virtual Camera feature remain in archive even if the camera is removed from a server.
A few notes about the Virtual Camera feature:
- Once uploaded into a Virtual Camera files cannot be overwritten.
- Motion detection for virtual camera footage must be enabled during upload or it will not be available subsequently.
- Make sure the server you select has enough storage space for the files being uploaded. If there is not enough available storage, the oldest existing archive may be deleted. Or, if the virtual camera footage is older than anything in archive, it can be uploaded but instantly deleted.
- Once storage blocks for a given time period are filled with virtual camera content, they cannot be overwritten. For example, if file "A" was recorded from 11:32 to 11:37, and file "B" was recorded from 11:35 to 11:38 on the same day, if one of the two has already been uploaded, the other file will not be, as they occupy some of the same storage blocks in archive. If the selected file covers a period for which video is already uploaded, you can upload it to a different virtual camera instead.
To Add a Virtual Camera
- Open the Main Menu and select New > Virtual Camera.
- In the dialog select a server from the pull-down menu.
- Enter a name for the virtual camera in the Name field. (If you do not enter a name, the default name "Virtual Camera" will automatically be appended with an integer that increments by 1.)
- Click OK to save or Cancel to exit without saving.
- In the Camera Settings dialog that opens, you can proceed to upload files immediately or at a later point.
To Upload Files to a Virtual Camera
Once added, the virtual camera will be displayed in the server Resource Tree, and files can be uploaded.
- Right click on the new Virtual Camera s.
- Use Default rotation option to rotate the virtual camera footage by 90, 180 or 270 degrees.
- Check Enable audio to include any audio tracks in the original footage.
- Use the Fixed Archive Length fields to assign high or low priority to the virtual camera (see "Configuring Minimum and Maximum Archive Storage").
- Check Detect motion in uploaded video, which will parse motion detection during file upload. Note that this option adds significant processing time. If motion detection is checked, you have the option to also adjust the Sensitivity setting (see "Setting up Motion Detection").
- Select Upload File to select a single file or Upload Folder to select all video files in a given directory.
- If there is limited storage space on the server, you will get a warning message with a prompt to continue or cancel. There is also an option to cancel upload from Camera Settings once upload is launched. If upload is canceled, any files that have already been uploaded will remain in storage.
- Upload will begin as soon as the file or folder is selected, and runs in background so you can perform other tasks simultaneously. An upload progress bar displays at the top of the Camera Settings dialog, and progress percentage is also shown in the Resource Tree.
- Once upload is complete, the video will launch and play automatically.
- If only virtual cameras are open in the layout, the Timeline will scale to show only the time interval spanning archive from those cameras. This is especially helpful when virtual camera footage is old and would be difficult to locate with the Timeline fully expanded to the present.
- If an audio track exists but is not audible, make sure Enable Audio in Camera Settings > General is checked.
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.
I am trying to upload a file to virtual camera, but the following error is shown:
Selected file does not have timestamp
Only video files with correct timestamp are supported.
How should I process a video file to fix it?
Our apologies for the delay in our reply.
As the error mentions, the file needs to have a correct timestamp to be supported.
If the timestamp isn't available, you can't add it as a virtual camera and can add it as a local file only with the following instructions:
When Nx Witness starts, it automatically indexes the designated local media folders and displays them under Local Files in the Resource Tree. The default media folders (customizable) are:
To add or remove a Media Folder
When Nx Witness restarts, files in the listed folders will display in the Resource Tree under Local Files.
To open local files that are outside the Media Folders
To view local files that are not shown in the Resource Tree, use one of the following:
Article is closed for comments.