Knowledge Base

Problem

Users attempting to manually correct tracking by clicking and dragging individual positional data points in the Track Editor find that this method does not work as expected or is not supported, leaving them unable to fix complex tracks.

Details

EthoVision XT's Track Editor is designed for specific correction operations (setting points to missing, interpolating, smoothing) rather than free-form dragging of individual points. Users performing complex behavioral analyses (e.g., visual behavior traces) that cannot be captured by automatic tracking attempt to manually place or drag points and encounter unexpected behavior. Affects all EthoVision XT versions with Track Editor.

Solution

1. Clicking and dragging individual track points in the Track Editor is not a supported operation in EthoVision XT due to the overlapping nature of densely sampled positional points.
2. Supported Track Editor corrections include: setting individual or ranges of samples to 'missing', interpolating across missing samples, and applying smoothing to reduce noise.
3. For systematic detection errors, the recommended approach is to return to the Arena/Detection settings and adjust detection parameters (threshold, subject size, algorithm), then re-track the video with the updated settings rather than manually correcting large numbers of points.
4. If the tracking task is inherently incompatible with EthoVision's automated detection (e.g., tracing fine visual behaviors frame by frame), consider whether Manual Scoring or a dedicated frame-by-frame annotation tool better suits the analysis goal.
5. For missing or erroneous samples near specific frames, use the Track Editor's 'Set to missing' function for those frames, then use linear interpolation to fill the gap smoothly.
6. Contact Noldus support to discuss whether a custom analysis approach or alternative workflow can meet your specific behavioral tracing requirements.