typed op• Data kinds: cimage → cimage
• Call: fullseye.apply(img, "tb_cx_apply_transfer_function", 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.*
Sweeping knob a (0.1 / 0.5 / 0.9, the other knob at its default):
▸ tb_cx_apply_transfer_function: knob a sweep (docs site)
*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_cx_apply_transfer_function: stages (docs site)
On other images (synthetic scene / photo / coins. Top row: inputs, bottom row: their outputs. Knobs at default):
▸ tb_cx_apply_transfer_function: other inputs (docs site)
Multiply a centred spectrum by a filter H -> (H, W) complex128.
The honest primitive under ops.lowpass / ops.highpass, but
complex-preserving: the filtered spectrum is returned as a complex field (not immediately inverted and real-cast), so it can be chained, inspected, or handed to cx_ifft. H is a same-shape transfer function laid out in the *centred* convention of cx_fft (DC at the centre); it may be real (a magnitude mask) or complex (a phase-shifting filter). A real cx is FFT'd first (module convenience).
Typed bridge of the 2d op cx_apply_transfer_function into the 2-D evolution registry: the same implementation, called under the op(v, a, b) convention. a sets the width of the transfer function H, which the bridge builds per call at the spectrum's own shape: a centred Gaussian low-pass H = exp(-r^2 / (2 sigma^2)) with sigma = 0.02 + 0.48 a cycles/pixel (0.26 at a=0.5). b is unused. (Until 2026-10-07 H was bound once as a fixed 32x32 array, so every other image size was refused.)
• 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_cimage 0.50 0.50 tb_cx_apply_transfer_function 0.50 0.50
▸ Load this pipeline · Load & run
• (none yet)
cimage as input)identity · tb_cx_ifft · tb_cx_magnitude · tb_cx_phase · tb_cx_real · tb_cx_imag · tb_cx_log_magnitude · tb_cplx_cr_residual
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.