frequency op• Data kinds: voxel → voxel
• Call: import fullseye as fs; fs.ledger.vol_fft_bandpass(vol, low, high, spacing=None) (to call the implementation directly, import volfreq; volfreq.vol_fft_bandpass(vol, low, high, spacing=None); from the registry, ops3d.get("vol_fft_bandpass"))
Gaussian band-pass lowpass(high) - lowpass(low): keeps structure between two scales.
low < high is required, both in cycles/voxel or cycles/mm with *spacing*. Typical use: isolate one texture scale, or a periodic artefact band before subtracting it.
The transfer function is exp(-|f|^2 / (2 high^2)) - exp(-|f|^2 / (2 low^2)). At DC it is 1 - 1 = 0, so the mean luminance drops out, and only a difference-of-Gaussians band with its peak between low and high (DoG type) remains. The peak height does not reach 1 (as it is the difference of 2 Gaussians, the closer low and high are, the smaller the passband gain). Returns float64 of the same (D, H, W) as the input, signed.
Arguments: low < high is required (both positive finite values). Units are cycles/voxel with spacing=None, and cycles/mm when spacing is given. Thinking in periods (voxel or mm), 1/high is the smallest structure size and 1/low the largest structure size.
Validation (ValueError): not 3-D / NaN, Inf / over MAX_VOXELS / low, high non-positive, non-finite, or their square (^2) underflows / low >= high / invalid spacing.
Use: extracting 1 texture scale; taking out a periodic stripe or ring artefact band and subtracting it from the input. vol_fft_lowpass(vol, high) - vol_fft_lowpass(vol, low) is equivalent.
• 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.
• deconv_fft_restore — py -3.11 examples_3d/deconv_fft_restore.py
voxel as input)voxel_to_mips · voxel_to_mesh · signed_distance_field · to_points · sobel3d · hessian3d · curvature_maps · edt_jfa
frequency)vol_fft_lowpass · vol_fft_highpass
*Provenance: volfreq.py — 3D 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.