Region adjacency graph (RAG) Thresholding#

This example constructs a Region Adjacency Graph (RAG) and merges regions which are similar in color. We construct a RAG and define edges as the difference in mean color. We then join regions with similar mean color.

plot rag mean color
from skimage import data, segmentation, color
from skimage import graph
from matplotlib import pyplot as plt

img =

labels1 = segmentation.slic(img, compactness=30, n_segments=400, start_label=1)
out1 = color.label2rgb(labels1, img, kind='avg', bg_label=0)

g = graph.rag_mean_color(img, labels1)
labels2 = graph.cut_threshold(labels1, g, 29)
out2 = color.label2rgb(labels2, img, kind='avg', bg_label=0)

fig, ax = plt.subplots(nrows=2, sharex=True, sharey=True, figsize=(6, 8))


for a in ax:


Total running time of the script: (0 minutes 1.909 seconds)

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