Laplace Interpolation
Fill masked (missing) regions by solving the Laplace equation with Dirichlet boundary conditions from surrounding pixels. Produces a smooth, harmonic interpolation without overshooting. Equivalent to Gwyddion's laplace.c module.
Inputs
| Name |
Type |
Required |
Description |
| field |
DATA_FIELD |
Yes |
Input field with regions to fill |
| mask |
IMAGE |
Yes |
Binary mask where white (255) marks pixels to interpolate |
Outputs
| Name |
Type |
Description |
| filled |
DATA_FIELD |
Field with masked regions filled by Laplace interpolation |
Controls
| Name |
Type |
Default |
Description |
| iterations |
INT |
500 |
Number of Jacobi relaxation iterations; more iterations = smoother result (10–10000) |
Notes
- Laplace interpolation produces the smoothest possible fill — it minimizes the integral of the squared gradient within the masked region.
- For small holes (<50 px diameter), 200–500 iterations is usually sufficient. Larger holes may need 1000+.
- Use a Draw Mask or Threshold Mask node to create the mask input.
- For surfaces with texture, consider Fractal Interpolation instead, which preserves surface roughness characteristics.
