Voronoi propagation from nuclear seeds — sg_segment

Expands nuclear seed regions outward using Voronoi-style propagation, optionally constrained by a membrane signal. When available, EBImage::propagate() is used for higher performance; otherwise a pure-R fallback is used.

Usage

sg_segment_propagate(
  image,
  nuclear_mask,
  membrane_image = NULL,
  lambda = 0.01,
  expand_max = 20L
)

Arguments

image: An sg_image object.
nuclear_mask: An sg_mask object providing the nuclear seed labels.
membrane_image: An sg_image object (single channel) used as a cost surface to penalise crossing membranes. If NULL, propagation proceeds uniformly.
lambda: Numeric weight for the membrane penalty in the cost function. Higher values make propagation stop more readily at membranes. Default is 0.01.
expand_max: Integer; maximum number of propagation iterations. Default is 20L.

Value

An sg_mask object with expanded cell labels.

Examples

set.seed(42)
pixels <- matrix(runif(400), nrow = 20, ncol = 20)
img <- new_sg_image(pixels)
seeds <- matrix(0L, nrow = 20, ncol = 20)
seeds[5, 5] <- 1L
seeds[15, 15] <- 2L
nuc_mask <- new_sg_mask(seeds)
result <- sg_segment_propagate(img, nuclear_mask = nuc_mask)
print(result)
#> <sg_mask>: 20 x 20, 2 cells
#> Method: propagate:ebimage