![]() You can also split the workspace and open up Graph view for another perspective. Double-click on the marker and the first gap will be shown in the 3D workspace. The gaps for the trial that you are working on will be in a drop-down list. Ultimately, the user must judge which is the best gap fill option.įind the Gap Filling window in the Label/Edit tab. Each has strengths and limitations, with different options preferable for certain situations. Vicon Nexus provides several gap filling options. A missing trajectory at the beginning or end of a trial will not register as a gap (a gap requires labelled trajectory either side of missing frames) but will register in the ‘Quality’ window as <100%. Selecting a marker will bring up slightly more detailed information. If you hover over a marker in the ‘Quality’ window, additional information will be presented (gaps, max gap length, % trial labelled). You can always check how much of your trial is present and labelled using the ‘Quality’ window (next to ‘Data Management’). In reality, there is rarely a 100% recording rate. Theoretically, all trajectories should be complete for the entire duration of a trial. Gap filling can only occur once labelling has begun. It is important to acknowledge that although these estimations can often look good, it is still an estimation and may not represent the true marker motion. We can fill that gap using one of several estimation methods and make a more complete trajectory. When a trajectory has no positional data for one or more frames, a gap is identified. These ‘tails’ can be toggled on/off in the Options menu (F7) under ‘Trajectories’, however it is recommended to leave them on, particularly during gap filling. ![]() Vicon Nexus visualises this trajectory with the blue line extending out from a selected marker a marker represents that trajectory’s position at the selected frame. The path that marker takes through space and time is its trajectory. ![]() When a marker is tracked during a trial, we are recording its position through time. Nexus 2 Tutorial – Fill Gaps and Filter Data Pipeline Operations.Gap filling should only be performed on dynamic experimental trials, never on any calibration trials or trials used for calibrating models. Gap filling can be very painful and tedious, So extra time spent pilot testing/calibrating to maximise marker tracking can save hours of post-processing. Sometimes these elements are unavoidable, but you should take as much time as possible to minimise their effect by pilot testing camera placements and settings prior to the actual data collection. This can be a result of many things: a person moving away from the calibrated volume, a poor calibration, or a marker being occluded from adequate camera view. Gap filling is required when a marker becomes occluded and cannot be accurately tracked.
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