K-means clustering based volume segmentation
Load a 3-D grayscale MRI volume and display it using
load mristack volshow(mristack);
Segment the volume into three clusters.
L = imsegkmeans3(mristack,3);
Display the segmented volume using
volshow. To explore slices of the segmented volume, use the Volume Viewer app.
V— Volume to segment
Volume to segment, specified as a 3-D grayscale volume of size m-by-n-by-p or a 3-D multispectral volume of size m-by-n-by-p-by-c, where p is the number of planes and c is number of channels.
imsegkmeans3 treats 2-D color images like 3-D volumes of size
m-by-n-by-3. If you want 2-D behavior, then
k— Number of clusters
Number of clusters to create, specified as a positive integer.
comma-separated pairs of
the argument name and
Value is the corresponding value.
Name must appear inside quotes. You can specify several name and value
pair arguments in any order as
NormalizeInput— Normalize input data
Normalize input data to zero mean and unit variance, specified as the
comma-separated pair consisting of
'NormalizeInput' and . If you specify
imsegkmeans3 normalizes each channel of the input
NumAttempts— Number of times to repeat the clustering process
3(default) | positive integer
Number of times to repeat the clustering process using new initial cluster
centroid positions, specified as the comma-separated pair consisting of
'NumAttempts' and a positive integer.
MaxIterations— Maximum number of iterations
100(default) | positive integer
Maximum number of iterations, specified as the comma-separated pair consisting of
'MaxIterations' and a positive integer.
Threshold— Accuracy threshold
1e-4(default) | positive number
Accuracy threshold, specified as the comma-separated pair consisting of
'Threshold' and a positive number. The algorithm stops when each
of the cluster centers move less than the threshold value in consecutive
L— Label matrix
Label matrix, specified as a matrix of positive integers. Pixels with label 1 belong
to the first cluster, label 2 belong to the second cluster, and so on for each of the
L has the same first three
dimensions as volume
V. The class of
on number of clusters.
|Class of ||Number of Clusters|
centers— Cluster centroid locations
Cluster centroid locations, returned as a numeric matrix of size
k-by-c, where k is the number
of clusters and c is the number of channels.
centers is the same class as the image
The function yields reproducible results. The output will not vary in multiple runs given the same input arguments.