flash_frequency — DRIVE decide op

• Data kinds: signal → table

• Call: import fullseye as fs; fs.ledger.flash_frequency(intensity_series, fps, *, f_min: 'float' = 0.0, pad: 'int' = 8) -> 'Dict[str, float]' (to call the implementation directly, import drivedecide; drivedecide.flash_frequency(intensity_series, fps, *, f_min: 'float' = 0.0, pad: 'int' = 8) -> 'Dict[str, float]'; from the registry, opsdrive.get("flash_frequency"))

Usage

Estimates the flashing frequency from the brightness time series of a pixel (or the mean of a region) (the highest peak of the FFT).

Subtract the mean, apply a Hann window, zero-pad to pad times the length, and rFFT. The highest peak at or above f_min is interpolated with a parabola in log amplitude. The returned frequency is the apparent frequency (flashing faster than fps/2 appears folded back to the value of aliased_frequency).

Return values: frequency, bin_width = fps / n (a guide to the window's resolution), nyquist = fps/2, peak_ratio (peak height / median outside the peak. Small for pixels that do not flash). A constant series (amplitude 0) raises ValueError.

References (sample data, literature)

• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).

• Operator provenance and references — the sources of the research/methods this op family came from.

• The canonical algorithm (author, year) and its uses are named in the family usage guide above.

Runnable examples (verified samples that actually call this op)

• poc_driving_crossing — py -3.11 examples/poc_driving_crossing.py

• poc_driving_decisions — py -3.11 examples/poc_driving_decisions.py

Ops the type connects to (they accept table as input)

course_layout · course_occupancy · course_contains · world_build · world_camera · world_move · lidar_scan · rss_longitudinal_same

Same category (decide)

mirror_reflection_matrix · mirror_virtual_camera · mirror_aim_normal · convex_mirror_fov · mirror_blind_zone · check_sequence_score · signal_phase_plan · signal_state

*Provenance: drivedecide.py — DRIVE operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.