tf_log_polar — 2D `geometry` op

• Data kinds: image → image

• Call: fullseye.apply(img, "tf_log_polar", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])

tf_log_polar: 入力 → 出力

*The figure is the real output on a synthetic 128×128 input. Left: input, right: output (a non-image return value is shown as the value itself).*

Usage

log_polar: resample the image on a log-polar grid about its centre.

Output row = log-radius (log-spaced from ~1px to `rmax`), output column =

angle (0..2pi). A scaling of the source about the centre becomes a vertical

(row) shift and a rotation becomes a horizontal (column) shift -- the defining

property of the log-polar transform. `a` scales the maximum sampled radius;

`b` adds a rotation offset (an angular shift) to demonstrate rotation ->

column-shift.

Detailed usage guide

• gallery2d_geometry family guide

References (sample data, literature)

• 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 canonical algorithm (author, year) and its uses are named in the family usage guide above.

Try it in Studio

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.

tf_log_polar 0.50 0.50

▸ Load this pipeline · Load & run

Runnable examples (verified samples that actually call this op)

• gallery2d_geometry — py -3.11 examples/gallery2d_geometry.py

Ops the type connects to (they accept `image` as input)

identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter

Same category (`geometry`)

rotate_img · rescale_img · affine_warp · sk_swirl · mirror_image · transpose_region · rotate_image · zoom_image_factor

*Provenance: ops.py — 2D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

tf_log_polar — 2D geometry op