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# Tracking Execution

Run the tracking pipeline, perform Volume Self-Calibration, and validate results in real-time.

## 1. Run Tracking Tab

### Execution Control

- Project Environment: Verify the correct project path is set.
- Run OpenLPT: Starts the main C++ tracking engine. The Execution Log tab on the left will stream real-time output.
- Stop Execution: Aborts the current process.

### Volume Self-Calibration (VSC)

Optimize camera parameters using tracked particles to correct for vibrations or setup shifts.

Best Practice: VSC works best with low concentration tracer images. Sparse data ensures reliable particle matches for calibration.
Workflow Loop:

1. Required: You must complete a full OpenLPT tracking run first to generate the tracks needed for VSC.
2. Calibrate: Run VSC to update camera parameters.
3. Verify & Refine: Run OpenLPT again to apply the new parameters. You can repeat this loop (OpenLPT → VSC → OpenLPT) to further refine the calibration.

Transferring Calibration to High-Density Data:

The optimized camera parameters are saved to the `camFile_VSC` folder.

To use this high-precision calibration for high-concentration tracer or bubble flow experiments:

1. Locate the folder `camFile_VSC` generated by your low-density VSC run.
2. Copy the contents (e.g., `cam0.txt`, `cam1.txt`...) into the Camera Path of your high-density project.
3. Run OpenLPT on the high-density data. The improved calibration will allow for tracking more particles with higher accuracy.

- Min Track Length: Only use tracks longer than this (e.g., 15 frames) for calibration.
- Sample Points: Total number of particle positions to use for optimization.
- Run VSC: Executes the self-calibration routine. Results are shown in the table below.

## 2. Visualization & Monitoring

### Left Panel Views

- 3D View: Interactive 3D plot of particle trajectories.
- 2D View: Shows camera images with reprojected particle positions. Use the checkboxes to toggle specific cameras.
- Execution Log: Displays stdout/stderr from the tracking engine.
- Timeline Slider: Scrub through the processed frames to inspect tracking evolution.

## 3. Check Tracking Tab

### Validation Tools

- Track Statistics: Displays "Total Tracks" and "Avg Track Length". Click refresh icon to update.
- Visualization Settings:
  - Display tracks slider: Control how many tracks are shown in the 3D view (e.g., top 500 longest).
  - Table Selection: View tracks in a table and select specific IDs to highlight.
- Animation Settings:
  - Enable Animation: Animate particle movement over time.
  - Tail Length: Number of past frames to show as a trail.
  - Start Animation: Begins playback in the 3D/2D views.