contour_to_img — 2D `bridge` op

• Data kinds: contour → image

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

contour_to_img: input → output

*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):

▸ contour_to_img: knob a sweep (docs site)

Sweeping knob b (0.1 / 0.5 / 0.9, the other knob at its default):

▸ contour_to_img: knob b sweep (docs site)

Stages (the ops that come before → this op, left to right):

▸ contour_to_img: stages (docs site)

On other images (synthetic scene / photo / coins. Top row: inputs, bottom row: their outputs. Knobs at default):

▸ contour_to_img: other inputs (docs site)

Usage

Draws an XLD contour back in the contour's own coordinate system — 43 ops produce contours, yet not even 1 op could turn one into an image.

The figure generator draws contours as polylines, but that is an implementation inside the tool and cannot be called from a registered op (it shows up neither in fullseye.apply nor in Studio).

• a → line thickness 1 + int(2a) (1 to 3 pixels).

• b → how darkness is assigned. b < 0.5 gives all the same darkness, b >= 0.5 gives darker for contours with more points (assigned 0.15 to 0.85 by rank). Which contours are the main ones is visible at a glance.

• Returns: float64 of the contours' shape (the size of the original image), dark lines on white. ★If there is not even 1 contour, a blank sheet is returned (not a black board).

Detailed usage guide

• gallery2d_bridge 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.

threshold 0.50 0.50
sk_find_contours 0.50 0.50
contour_to_img 0.50 0.50

▸ Load this pipeline · Load & run

Runnable examples (verified samples that actually call this op)

• gallery2d_bridge — py -3.11 examples/gallery2d_bridge.py

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

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

Same category (`bridge`)

img_to_points · img_to_keypoints · img_to_signal · img_to_projection_profile · img_to_counts · img_to_matrix · img_to_video · img_to_volume

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

contour_to_img — 2D bridge op