``Marker-based_WS_relax'' - segment an image using watershed relaxation using markers

VFX name:

iWS_MarkerRelax

IMPROMPTU Equivalent:

Marker-based_watershed_relax

purpose:

Watershed Relaxation uses both Watershed analysis [] and Relaxation labeling [7] to perform segmentation. Watershed analysis using markers is performed initially on the gradient of image to produce basins. Relaxation labeling is performed on the resultant basins to produce a segmented output image. Thus, it uses, speed of watershed analysis and region smoothing property of relaxation labeling to produce a better segmented output when compared to watershed analysis alone.

input:

Two 8-bit volumes ( original image and gradient image).

output:

An 8-bit volume in segmentation volume format (refer to the demask region function, p. ) containing the segmented regions .

parameters:

Default parameters menu is

grad_vol = 0
marker_slice = 2
num_regions = 2
Region 1 parameters:
first_mean: 0
first_std_dev 0
Region 2 parameters:
second_mean: 0
second_std_dev 0
Region 3 parameters:
third_mean: 0
third_std_dev 0
Region 4 parameters:
fourth_mean: 0
fourth_std_dev 0
num_iter = 10
percent_neigh = 25.0
final_seg_thresh = 0.0

If the final segmentation threshold is set to 0.0, then the maximum vector component for each voxel is assumed to represent that voxel's appropriate labeling. If a threshold is set, then the maximum vector component value for a voxel must be greater than the threshold value for that voxel to be labeled as part of a region.

comments:

See below.

1.

See Cue-based_WS_relax for a comparable function.