Capture tools

The Capture Tools pane enables you to collect motion data.

Collecting motion data involves identifying where in a motion capture trial database to store the data, specifying the type of source data that is to be captured, optionally configuring any remote triggering, optionally determining any automated processing to be performed, and managing the capture process. You can capture trials manually or configure Nexus to capture trials automatically.

For basic instructions on collecting data, see Capture movement trials in the Vicon Nexus User Guide.

The Capture Tools pane contains the following sections:

• Trial Type list Create or manage configurations for the motion capture trial types specified in the Capture Tools using the configuration management section at the top of the pane. (For information on managing configurations, see Manage configurations in Vicon Nexus in the Vicon Nexus User Guide.)
• Next Trial Setup Specify identification and information details for the way Nexus is to store data for this trial in a motion capture database:
  
  • Session A link to the active subject\session node in the currently loaded trial database. Click the link to open the Communications window, displaying the Data Management tab, or bring it to the front if it is already open, with the active node highlighted. If you make a different session the active node, the Session link is updated.
    Default: Identified by system
  • Trial Name The name under which to save the trial data in the motion capture database.
    Default: Blank if you are creating a new trial in a new session, or if the trial is the latest of several in a session and Auto increment is selected (see below), the system automatically names it after the preceding trial and increments numbering by 1.
    Do not use the following special characters in a trial name:
    \ backslash
    . period
    / slash
    , comma
    < left angle bracket
    ? question mark
    > right angle bracket
    *asterisk
    : colon
    " double quotation mark
    | vertical bar
    % percent
    $ dollar sign
  • Description Enter any description you want to specify for the trial. This description is displayed on the Data Management tab in the row associated with the captured trial.
    Default: Blank
  • Notes Enter any notes you want to specify for the trial. These notes are displayed on the Data Management tab in the row associated with the captured trial.
    Default: Blank
  • Auto increment trial number Choose whether or not to have Nexus automatically add a numerical suffix to the trial name for each subsequent trial, for example, Trial001, Tria002, Trial003, etc.
    Default: Selected
  • Permit overwrite of existing files Choose whether or not to have Nexus overwrite an existing data file without prompting you with a warning that it has the same name as that specified in the Trial Name field with this trial data.
    Note that if Auto increment trial number is selected and the file name that would be created using the next sequential numerical suffix is the same as that for an existing file, that previous file is overwritten.
    Default: Cleared

• Data Source Setup Specify the type of motion data to be captured by your Nexus system in the Data Source Setup section of the Capture Tools pane:
  
  • Device Data Analog signals captured by any third-party devices such as force plates or EMG devices.
    Default: Selected
  • Optical Camera Data Marker images visible to the Vicon optical cameras
    Default: Selected
  • Video Camera Data Digital video captured by any connected digital video cameras.
    Default: Selected
• Auto Capture Setup You can configure Vicon Nexus to automatically capture trials using the following controls:
  
  • Range Use an external remote control device to trigger data capture in your Vicon system. The remote control device must be connected to a Vicon Lock unit in your Vicon system (for details, see Vicon Vantage Reference Guide), and the sync outputs (GPO pins) for the remote functionality must be configured under the relevant Vicon Connectivity node in the System Resources pane.
    
    • Capture before Start Specify the number of seconds of data to record prior to capture being triggered either manually (with the Start button) or automatically (based on timecode or a remote control device).
    • Stop after duration Specify the number of seconds of data to record after which capturing will automatically stop.
  • Triggers Use a labeling percentage value that you specify or an external timecode source to trigger data capture in your Vicon system. The timecode source must be connected to an a Vicon Lock unit (for details, see Vicon Vantage Reference Guide), and the corresponding timecode options must be configured under the relevant Vicon Connectivity node in the System Resources pane.
    
    • Start on Labeling (%) Captures automatically start when a subject first fully enters the volume. Set the labeling percentage (ie, the percentage of markers expected from the total number of markers in your subject's labeling skeleton) that needs to be recognized by Nexus within the capture volume for the subject to be considered as fully in the volume and therefore to trigger capture start.
    • Stop on Labeling (%) Captures automatically stop when the subject leaves the volume. Set the labeling percentage (ie, the percentage of markers expected from the total number of markers in your subject's labeling skeleton) that needs to be recognized by Nexus within the capture volume for the subject to be considered to have left the volume and therefore to trigger capture stop.
    • Start/Stop on remote trigger Start and/or stop capture on the activation of a remote trigger. This option is disabled if no remote trigger devices are recognized.
      Trigger the start of the capture from your remote control device.
      After you have acquired the data you need, trigger the stop of the capture from your remote control device.
    • Start on Timecode Select this check box and specify the timecode at which capture should automatically start.
    • Stop on Timecode Select this check box and specify the timecode at which capture should automatically stop.
      For further details on the use of timecode functionality in Vicon systems, see the Vicon Vantage Reference Guide.
  • Start/Stop over network Broadcast a UDP message over an intranet or direct network cable connection to or from another application (or instance of Nexus) to trigger capture start and stop.
  • Address Enables you to select the network interface (first field) and UDP port (second field) on which to broadcast.
  • Arm button To set the system to a state where it is ready to accept a trigger signal for automatic capture based on a remote control device, click the Arm button.
  • Lock button If you want to enable the system to remain ready to receive subsequent remote capture signals after the capture is stopped, click the Lock button to the right of the Arm button.
• Post-Capture Pipeline Setup Enables you to specify any automatic post-processing that you want Nexus to perform on the captured data:
  • Run pipeline after capture Whether or not to run a previously defined pipeline immediately after the trial is captured. Select the pipeline that you want from the drop-down list.Default: Cleared
• Capture section Enables you to manage the motion capture process and view the number of frames captured and the current duration in seconds during processing:
  
  • Start/Stop Click this button to start a capture. When clicked, the button switches to the Stop setting.If you have set the Stop after Duration or Stop on Timecode settings in the Auto Capture Setup section, or if there is data in the buffer that has still to be written to disk, the button switches to Stopping until the capture has completed. If you click the button while it displays Stopping, the capture stops, and you will lose any data that was due to be captured, or that is currently in the buffer but not yet written to disk.
  • Cancel Click this button to cancel an active capture.
  • Frames Captured Displays the number of frames captured in the current trial. This number increments until the motion capture process is stopped.
  • Trial time The amount of time elapsed during the current capture is displayed in hh:mm: ss(ff) format, where hh is hours, mm is minutes, ss is seconds and ff is frames. For example, a 2.5 second capture at 50 Hz (125 frames) is displayed as 00:00:02(125).