typed op• Data kinds: beatcube → image
• Call: fullseye.apply(img, "tb_range_doppler_map", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
*The figure is the actual output on a synthetic 128×128 input. Left: input, right: output. Point clouds are drawn as a top-down scatter (brightness = z), 1-D series as a line plot, volumes as the maximum-intensity projection along z, videos as the middle frame, complex images as magnitude; return values that are not pictures are shown as the values themselves.*
*Knob a does not change the output (measured: identical at 0.1 / 0.5 / 0.9).*
*Knob b does not change the output (measured: identical at 0.1 / 0.5 / 0.9).*
Stages (the ops that come before → this op, left to right):
▸ tb_range_doppler_map: stages (docs site)
On other images (synthetic scene / photo / coins. Top row: inputs, bottom row: their outputs. Knobs at default):
▸ tb_range_doppler_map: other inputs (docs site)
The 2-D FFT of a beat cube -> a `(n_doppler, n_range)` magnitude map.
Fast time transforms to range (last axis, not shifted: bin `j` is
`j * c*f_s/(2*S*N_s)` metres, and a physical range is always positive so
the whole `[0, f_s)` band is used). Slow time transforms to velocity
(middle axis, `fftshift`ed so the map is centred on zero velocity: bin
`i is (i - N_c//2) * lambda/(2*N_c*T_c)` metres per second, positive =
receding).
The antenna axis is collapsed by *combine*: `"incoherent"` (default) is the
mean of the magnitudes, which is angle independent and therefore the
right default for detection; `"coherent"` is the magnitude of the mean,
i.e. a beam pointed at boresight, which attenuates an off-boresight target on
purpose. `antenna=k uses element k` alone. For a single-element cube
all three agree exactly.
`normalize=True divides by N_c * N_s`, so a bin-centred target of
amplitude `a peaks at exactly a` (measured: 1.0 for a unit target,
absolute error 0.0). The default `False` keeps the raw FFT magnitude.
No window is applied — compose :func:fmcw_window_apply first if you want
one. The output is a plain 2-D float64 array, so every 2-D operator in
Fullseye (threshold, morphology, labelling, blob measurement — the pieces a
CFAR detector is made of) applies to it directly.
Raises `ValueError`: a real-valued cube (it would put a mirror ghost of
every target at a fabricated range), fewer than 2 chirps or 2 samples, an
out-of-range *antenna* index, an unknown *combine*, a cube over the element
cap, an FFT that overflows to NaN, or NaN/Inf on the way in.
Typed bridge of the rangedoppler op `range_doppler_map into the 2-D evolution registry: the same implementation, called under the op(v, a, b) convention. This op has no tunable parameter; a and b` are unused.
• 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 program below has been verified to run (same input as the figure). In Studio's help this block becomes buttons that load and run it on the spot.
img_to_beatcube 0.50 0.50 tb_range_doppler_map 0.50 0.50
▸ Load this pipeline · Load & run
The examples below call the underlying ledger op range_doppler_map. This bridge op is the same implementation adapted to the fn(v, a, b) convention, so the behaviour carries over unchanged (only the call form differs).
• fmcw_range_doppler — py -3.11 examples/fmcw_range_doppler.py
image as input)identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter
typed)tb_points_to_voxel · tb_estimate_point_normals · tb_iss_keypoints · tb_project_points · tb_render_point_depth · tb_statistical_outlier_removal · tb_radius_outlier_removal · tb_voxel_grid_downsample
*Provenance: ops.py — 2D 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.