dtof ophistcube → depthimport fullseye as fs; fs.ledger.dtof_cube_depth(cube, bin_ps=100.0, mode='peak', offset_ps=0.0, min_counts=1.0, empty_value=0.0, subtract_background=False) (実装を直接呼ぶなら import photoncount; photoncount.dtof_cube_depth(cube, bin_ps=100.0, mode='peak', offset_ps=0.0, min_counts=1.0, empty_value=0.0, subtract_background=False)、台帳から引くなら opsphoton.get("dtof_cube_depth"))Depth map from a (H, W, T) photon histogram cube — the dToF inversion.
The array version of :func:dtof_depth, with the same four mode estimators
and the same t_flight = t_measured - offset_ps sign convention. The time
axis is last: a (D, H, W) voxel volume passed in here would be read as
W time bins and return a plausible-wrong depth map, so the shape is
checked and the error message says exactly that.
Pixels whose total counts are below min_counts — and, in the peak-based
modes, pixels whose histogram is exactly flat (no peak to find, so
argmax would report bin 0 for every one of them) — are set to
empty_value (default 0.0, a value no real return can have since
d > 0). Set
empty_value=float('nan') if you would rather propagate a NaN — that is an
opt-in, never the default, because a NaN depth map silently poisons every
downstream reduction.
Where a sub-bin mode cannot be applied to a pixel — the peak is in the
first or last bin, or the three samples are flat / non-positive for the log
fit — that pixel falls back to the bin-centre ("peak") estimate. A
per-pixel exception would be useless on a megapixel cube; the fallback is
documented here and pinned in the tests, and it degrades to the coarser
estimator rather than to a wrong one.
Ground truth: on a noiseless simulated cube of a tilted plane from 1.0 to
3.0 m (32x32 pixels, 256 bins x 100 ps, 500 ps IRF) the RMS depth error is
4.39 mm for "peak", 3.2e-16 m for "centroid", 0.114 mm for
"parabolic" and 1.6e-8 m for "gaussian". With Poisson noise (20
signal + 5 ambient photons per pixel, seed 0) the same four give 19.9 mm,
164.8 mm (background subtracted), 18.7 mm and 19.2 mm — at 20 photons the
estimator choice is worth about 6%, and the centroid is 8x worse than doing
nothing clever at all.
Returns a float64 (H, W) depth map in metres.
Raises ValueError: a cube that is not 3-D / has fewer than 2 time
bins / holds negative counts / exceeds :data:MAX_CUBE_ELEMENTS, a
non-positive bin_ps, an unknown mode, a negative min_counts, a
non-finite empty_value other than NaN, and — instead of returning negative
distances — an offset_ps that exceeds the measured arrival time of any
valid pixel (a mis-signed or mis-scaled calibration delay).
py -3.11 examples/photon_timeresolved.pypy -3.11 examples/poc_dtof_ranging.pydepth を入力に取れる)dtof)dtof_depth · dtof_cube_simulate
Provenance: photoncount.py — PHOTON operator registry. この per-op ノートは tools/opdocs.py md が自動生成(手編集しない)。
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.