match_pose op• Data kinds: voxel × voxel → rot_scale
• Call: import fullseye as fs; fs.ledger.match_logpolar_z(a, b, device='cpu', project='mip', nt=360, nr=192) (to call the implementation directly, import match3d; match3d.match_logpolar_z(a, b, device='cpu', project='mip', nt=360, nr=192); from the registry, ops3d.get("match_logpolar_z"))
• GPU: this op has a GPU path (device="cuda")
Recover rotation about z and isotropic scale by log-polar × phase correlation (Fourier-Mellin).
Structure = voxel × method = Fourier-Mellin. Whereas PCA needs point correspondences, this needs no template/correspondence and is the only column that estimates rotation (about the z axis) and scale together. Core idea: taking the z projection (MIP) reduces z-axis rotation to in-plane rotation and isotropic scale to in-plane scale, so the established 2D Fourier-Mellin (|FFT| → high-frequency emphasis → log-polar → phase correlation) can be used. Returns (angle_deg, scale).
Honest limits (a coarse estimator; assumes NCC/ICP refinement downstream): error ~2-5° for |rotation|≲40°. |FFT| has a 180° symmetry, so angles near ±45°/±90° alias and may miss. Scale comes out ~10% too small due to central-lobe bias. Full whitening zero-locks on the unshifted DC plateau of this projection, so plain correlation + a rho-Hann window + parabolic sub-pixel is used.
Arguments: a, b are 3-D volumes (they need not have the same shape, but if the aspect ratios of the projections differ, the log-polar correspondence breaks). project="mip" gives the maximum intensity projection along axis 0, anything else the sum projection along axis 0. nt/nr are the numbers of log-polar angle and radius samples (angular resolution 180°/nt). Returns (angle_deg, scale): estimates that b is a rotated by angle_deg about axis 0 and scaled by scale (b ≈ zoom(rotate(a, angle_deg, axes=(1,2)), scale); the rotation direction is the same as scipy.ndimage.rotate). The angle aliases within the range ±90°.
Downstream: home in with refine_rotation_z(scene=b, template=a, init_angle_deg=angle_deg) → translation with match_phase_3d.
• 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.
• shape_desc_pose — py -3.11 examples_3d/shape_desc_pose.py
rot_scale as input)match_pose)match_phase_3d · match_pca · moment_axes
*Provenance: match3d.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.