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TrackerDefaults

Global auto-tracking defaults. The start and stop bars on this page are on the scale of the number that TrackedBody.TrackingQuality reports, and that scale depends on the method. TrackingQuality of a silhouette body is the histogram score, and ShapeQuality uses variance StdDev. The tuning constants of the registration margin and of recovery are internal.

Constant Value Description
QUALITY_TO_START 0.3 The start bar of a silhouette body. It is used as set, so a silhouette body starts at 0.3.
FRAMES_TO_START 5 Consecutive frames with good quality required before starting.
FRAMES_TO_LOSE 5 Consecutive frames with bad quality required before stopping.
STABILIZATION_FRAMES 30 Frames after tracking starts before quality-based decisions (loss/SLAM entry) are allowed.
LOSE_TRACKING_THRESHOLD 0.4 The stop bar of a silhouette body. The averaged score must stay at or above it.
SD_MIN 0.10 StdDev floor for the perfect shape fit. Correct models typically achieve ~0.10-0.16.
SD_MAX 3 StdDev ceiling for poor shape fit. Wrong models can show sd > 1.0.
HISTOGRAM_GOOD 0.7 Histogram discriminability value for good tracking (maps to quality 1.0). Also used as default/reset value for global peak.
HISTOGRAM_BAD 0.0 Histogram discriminability value for poor tracking (maps to quality 0.0).
PEAK_MIN 0.6 Minimum value for global histogram peak. Floor for quality reference.
PEAK_MAX 0.85 Maximum value for global histogram peak. Ceiling for quality reference.
PEAK_DECAY_RATE 0.9995 Peak decay rate per frame. At 60fps, 0.9995 = ~3% decay per second.
STATIONARY_FRAMES_TO_RECOVER 5 Consecutive good frames before exiting SLAM recovery.
EDGE_QUALITY_TO_START 0.65 The start bar of a body that tracks by the edge method.
EDGE_QUALITY_TO_CONFIRM_START 0.65 The score the last frame of a start must reach for a body that tracks by the edge method and reads the coverage score. It equals the start score, so a start needs the start score on 5 frames in a row and nothing more. A confirm score at or below the start score withholds nothing.
EDGE_LOSE_TRACKING_THRESHOLD 0.5 The stop bar of a body that tracks by the edge method without pose fusion. The averaged score must stay at or above it.
EDGE_QUALITY_COVERAGE_MAX 0.55 Edge coverage value that maps to quality 1.0 via InverseLerp(0, this, coverage), for a body that does not read the shipped scale. A body that tracks by the edge method without pose fusion maps a coverage share of 0.70 to quality 1.0.
EDGE_RESIDUAL_MAX 15 Edge median residual (pixels) fallback when no valid edge points.
EDGE_PROJECTION_ERROR_BAD 30 Projection error (degrees) fallback when no valid edge points.
DEFAULT_SMOOTH_TIME 0.1 Default smooth time in seconds for stationary pose corrections. 0 = instant.
STATIONARY_SETTLE_PULL 0.05 How far the settled pose of a stationary body moves toward each verified solve while the solve stands close to it. This averages the scatter of the solve.
STATIONARY_SETTLE_STILL_PIXELS 1.5 On-screen distance in pixels, as the median displacement of the model's points, up to which a verified solve counts as scatter and is averaged.
STATIONARY_SETTLE_MOVE_PIXELS 4 On-screen distance in pixels from which a verified solve counts as the object having moved, and the settled pose is seated on the solve. Between the two distances the pull grows in proportion.