Mask Noisify
Add random noise to a binary mask by flipping pixels near boundaries. Equivalent to Gwyddion's mask_noisify.c.
Inputs
| Name |
Type |
Required |
Description |
| mask |
IMAGE |
Yes |
Binary mask to perturb |
| field |
DATA_FIELD |
No |
Optional field for preview background display |
Outputs
| Name |
Type |
Description |
| mask |
IMAGE |
Noisified binary mask |
Controls
| Name |
Type |
Default |
Description |
| density |
FLOAT |
0.1 |
Fraction of candidate pixels to flip (0.0--1.0) |
| direction |
dropdown |
both |
Which pixels to perturb: add (grow mask), remove (shrink mask), or both |
| boundaries_only |
BOOLEAN |
True |
Only modify pixels adjacent to a mask boundary |
| seed |
INT |
42 |
Random seed for reproducible results (0--999999) |
Notes
- Boundary detection uses four-neighbour comparison (up, down, left, right) via np.roll. A pixel is a boundary pixel if it differs from at least one of its four neighbours.
- Direction modes control which candidates are eligible: "add" selects only unmasked boundary pixels, "remove" selects only masked boundary pixels, and "both" selects all boundary pixels.
- Setting boundaries_only to False allows any pixel in the mask to be a candidate, not just those at edges.
- The seed parameter ensures deterministic output for a given input, which is useful for repeatable experiments.
