コード例 #1
0
def hierarchical_merging_of_region_boundary_rags_example():
    #img = data.coffee()

    edges = sobel(skimage.color.rgb2gray(img))

    labels = slic(img, compactness=30, n_segments=400)
    g = graph.rag_boundary(labels, edges)

    graph.show_rag(labels, g, img)
    plt.title('Initial RAG')

    labels2 = graph.merge_hierarchical(labels,
                                       g,
                                       thresh=0.08,
                                       rag_copy=False,
                                       in_place_merge=True,
                                       merge_func=merge_boundary,
                                       weight_func=weight_boundary)

    graph.show_rag(labels, g, img)
    plt.title('RAG after hierarchical merging')

    plt.figure()
    out = skimage.color.label2rgb(labels2, img, kind='avg')
    plt.imshow(out)
    plt.title('Final segmentation')

    plt.show()
コード例 #2
0
ファイル: utils_img.py プロジェクト: JuanIgnacioCG/prueba
def show_segmen_rag(array,
                    pathlibpath,
                    numSegments,
                    threshold,
                    cedges=177,
                    compactness=0.1,
                    sigma=5,
                    convert2lab=False):
    print('Obtaining superstructures')
    segments = slic(array,
                    compactness=compactness,
                    n_segments=numSegments,
                    sigma=sigma,
                    multichannel=False,
                    convert2lab=convert2lab)
    print('Number of SV: ', len(np.unique(segments)))
    segments += 1
    edges = filters.sobel(array)
    print('Obtaining RAG')
    rag = graph.rag_boundary(segments, edges, connectivity=1)
    segments2 = graph.merge_hierarchical(segments,
                                         rag,
                                         threshold=threshold,
                                         in_place_merge=True,
                                         rag_copy=False,
                                         merge_func=merge_boundary,
                                         weight_func=weight_boundary)
    print('Final Number of SV: ', len(np.unique(segments2)))

    graph.show_rag(segments, rag, array, edge_cmap='viridis')
    save_yorno(array, segments, pathlibpath, cedges)
コード例 #3
0
    def plotRagwithColorMaps(self, img, labels):
        g = graph.rag_mean_color(img, labels)
        fig, ax = plt.subplots(nrows=2,
                               sharex=True,
                               sharey=True,
                               figsize=(6, 8))

        ax[0].set_title('RAG drawn with default settings')
        lc = graph.show_rag(labels, g, img, ax=ax[0])
        # specify the fraction of the plot area that will be used to draw the colorbar
        fig.colorbar(lc, fraction=0.03, ax=ax[0])

        ax[1].set_title('RAG drawn with grayscale image and viridis colormap')
        lc = graph.show_rag(labels,
                            g,
                            img,
                            img_cmap='gray',
                            edge_cmap='viridis',
                            ax=ax[1])
        fig.colorbar(lc, fraction=0.03, ax=ax[1])

        for a in ax:
            a.axis('off')

        plt.tight_layout()
        plt.show()
コード例 #4
0
def generate_texture(img,
                     slic_n=200,
                     slic_compactness=25,
                     rag_from_binary=False,
                     edge_threshold=1e-4,
                     verbose=False):
    img = img_as_float(img)

    if rag_from_binary:
        if verbose:
            print('Applying initial thresholding...', flush=True)
        grey_img = color.rgb2grey(img)
        binary_mask = (grey_img > threshold_li(grey_img)) * 1.0

    if verbose:
        print('Constructing superpixels...', flush=True)
    segments = slic(img, n_segments=slic_n, compactness=slic_compactness)
    if verbose:
        out_avg = color.label2rgb(segments, img, kind='avg')
        io.imshow(out_avg)
        io.show()

    if verbose:
        print('Building RAG...', flush=True)
    if rag_from_binary:
        RAG = graph.rag_mean_color(binary_mask, segments, mode='similarity')
    else:
        RAG = graph.rag_mean_color(img, segments, mode='similarity')
    if verbose:
        graph.show_rag(segments, RAG, img, border_color=(1, 0.7, 0))
        io.show()

    foreground_mask = find_foreground(img,
                                      segments,
                                      RAG,
                                      eps=edge_threshold,
                                      verbose=verbose)

    if foreground_mask.any():
        vertex, side = fit_square(foreground_mask, verbose=verbose)
        texture_patch = img[vertex[0]:vertex[0] + side + 1,
                            vertex[1]:vertex[1] + side + 1]
        if verbose:
            io.imshow(texture_patch)
            io.show()
        return texture_patch
    else:
        print('Texture can\'t be generated, try different parameters')
        return np.array([])
コード例 #5
0
def make_grid_rag(data, res):

    fig, ax = plt.subplots(len(res), 2)
    ax = ax.reshape(len(res), 2)
    # make preview images
    im = data['image_unnormal'].cpu().numpy()
    im = [np.rollaxis(im[i, ...], 0, 3) for i in range(im.shape[0])]
    truth = data['label/segmentation'].cpu().numpy()
    truth = [truth[i, 0, ...] for i in range(truth.shape[0])]
    labels = data['labels'].cpu().numpy()
    labels = [labels[i, ...][0] for i in range(labels.shape[0])]
    for i, (im_, truth_, labels_,
            g) in enumerate(zip(im, truth, labels, data['rag'])):
        truth_contour = segmentation.find_boundaries(truth_, mode='thick')
        g.add_edges_from(
            (e[0], e[1], dict(weight=res[i][j].detach().cpu().numpy()))
            for j, e in enumerate(g.edges))
        lc = show_rag(labels_.astype(int),
                      g,
                      im_,
                      ax=ax[i, 1],
                      edge_width=0.5,
                      edge_cmap='viridis')
        fig.colorbar(lc, ax=ax[i, 1], fraction=0.03)
        im_[truth_contour, ...] = (1, 0, 0)
        ax[i, 0].imshow(im_)

    return fig
コード例 #6
0
ファイル: im_utils.py プロジェクト: AmmieQi/ksptrack
def make_grid_rag(im, labels, rag, probas, truth=None):

    fig = plt.figure()
    ax = plt.gca()

    # make preview images
    rag.add_edges_from([(n0, n1, dict(weight=probas[j]))
                        for j, (n0, n1) in enumerate(rag.edges())])

    lc = show_rag(labels.astype(int),
                  rag,
                  im,
                  ax=ax,
                  edge_width=0.5,
                  edge_cmap='viridis')
    fig.colorbar(lc, ax=ax, fraction=0.03)
    if (truth is not None):
        truth_contour = segmentation.find_boundaries(truth, mode='thick')
        im[truth_contour, ...] = (255, 0, 0)
    ax.axis('off')
    ax.imshow(im)

    fig.tight_layout(pad=0, w_pad=0)
    fig.canvas.draw()
    im_plot = np.array(fig.canvas.renderer.buffer_rgba())[..., :3]
    plt.close(fig)
    return im_plot
コード例 #7
0
def merge_hier_boundary(labels, image, thresh=0.03, show_rag=False):
    """
    Merges the given labels using a RAG based on boundaries.

    Parameters
    ----------
    labels: ndarray
    image: ndarray
    thresh: float
    show_rag: bool
    
    Returns
    -------
    rag: RAG
    labels: ndarray
        Merged labels.
    """
    edges = filters.sobel(color.rgb2gray(image))
    rag = graph.rag_boundary(labels, edges)
    rag_copy = False
    if show_rag:
        rag_copy = True
        fig, ax = plt.subplots(1, 2, figsize=(10, 10))

    labels = graph.merge_hierarchical(labels,
                                      rag,
                                      thresh=thresh,
                                      rag_copy=rag_copy,
                                      in_place_merge=True,
                                      merge_func=merge_boundary,
                                      weight_func=weight_boundary)
    if show_rag:
        graph.show_rag(labels, rag, image, ax=ax[0])
        ax[0].title('Initial RAG')
        graph.show_rag(labels, graph.rag_boundary(labels, edges), ax=ax[1])
        ax[1].title('Final RAG')

    return rag, labels
コード例 #8
0
def merge_hier_color(labels, image, thresh=0.08, show_rag=False):
    """
    Merges the given labels using a RAG based on the mean color.

    Parameters
    ----------
    labels: ndarray
    image: ndarray
    thresh: float
    show_rag: bool

    Returns
    -------
    rag: RAG
    labels: ndarray
        Merged labels.
    """
    rag = graph.rag_mean_color(image, labels)
    rag_copy = False
    if show_rag:
        rag_copy = True
        fig, ax = plt.subplots(1, 2, figsize=(10, 10))
    labels = graph.merge_hierarchical(labels,
                                      rag,
                                      thresh=thresh,
                                      rag_copy=rag_copy,
                                      in_place_merge=True,
                                      merge_func=merge_mean_color,
                                      weight_func=_weight_mean_color)
    # labels2 = graph.cut_normalized(img_slic, rag, thresh=30)
    # labels2 = graph.cut_threshold(img_slic, rag, 0.2)
    if show_rag:
        graph.show_rag(labels, rag, image, ax=ax[0])
        ax[0].title('Initial RAG')
        graph.show_rag(labels, graph.rag_mean_color(image, labels), ax=ax[1])
        ax[1].title('Final RAG')

    return rag, labels
コード例 #9
0
def region_boundry(image):
    
    #image = imageGlobal

    labels = segmentation.slic(image, compactness=30, n_segments=400)
    edges = filters.sobel(image)
    edges_rgb = color.gray2rgb(edges)

    g = graph.rag_boundary(labels, edges)
    lc = graph.show_rag(labels, g, edges_rgb, img_cmap=None, edge_cmap='viridis',
                        edge_width=1.2)

    plt.colorbar(lc, fraction=0.03)
    io.show()
コード例 #10
0
def desenho_rag(rag, labels):
    '''
        Parametro: 
            labels: array 2d
            grafo
            Imagem
        retorno:
            nada
        
        Imprime o grafo em cima da imagem
    '''
    global image
    lc = graph.show_rag(labels, rag, image)        
    
    plt.colorbar(lc, fraction=0.03)
    io.show()
コード例 #11
0
def make_network(mask, draw=False, save_loc=None):
    orig, image_labels, edge_map = get_img_labels_edge_map(mask)
    g = graph.rag_boundary(image_labels, edge_map)
    g.remove_node(0)
    if draw:
        fig, ax = plt.subplots(2, 2, figsize=(15, 15), dpi=200)
        ax = ax.ravel()
        ax[0].imshow(orig, cmap='gray')
        ax[2].imshow(label2rgb(image_labels, image=orig))
        ax[1].imshow(edge_map)
        lc = graph.show_rag(image_labels,
                            g,
                            edge_map,
                            ax=ax[3],
                            edge_width=5,
                            edge_cmap='Blues')

        fig.colorbar(lc, fraction=0.03, ax=ax[3])
        pos = {}
        for idx in list(g.nodes):
            pos[idx] = (np.array(g.nodes[idx]['centroid'])[::-1])
        nx.draw(g, pos, ax=ax[3])
        for a in ax:
            a.grid('off')
        fig.tight_layout()

        if save_loc is not None:
            fig.savefig(save_loc)
    else:
        # because if we don't draw then these features aren't added to the graph
        props = regionprops(image_labels)
        for (n, data), region, idx in zip(g.nodes(data=True), props,
                                          range(len(props))):
            data['centroid'] = tuple(map(int, region['centroid']))
            data['uid'] = idx
    return g
コード例 #12
0
def region_boundry(img):
    gimg = color.rgb2gray(img)

    fig, ax = plt.subplots(nrows=1)

    labels = segmentation.slic(img, compactness=30, n_segments=400)
    edges = filters.sobel(gimg)
    edges_rgb = color.gray2rgb(edges)

    g = graph.rag_boundary(labels, edges)
    lc = graph.show_rag(labels,
                        g,
                        edges_rgb,
                        img_cmap=None,
                        edge_cmap='viridis',
                        edge_width=1.2)

    ax.imshow(cv2.cvtColor(img, cv2.COLOR_BGR2RGB))
    ax.set_title("Original Image")

    plt.colorbar(lc, fraction=0.03)

    plt.tight_layout()
    plt.show()
コード例 #13
0
g = graph.rag_mean_color(p1, labels)

# In[33]:

labels2 = graph.merge_hierarchical(labels,
                                   g,
                                   thresh=0.025,
                                   rag_copy=True,
                                   in_place_merge=True,
                                   merge_func=merge_mean_color,
                                   weight_func=_weight_mean_color)

# In[34]:

graph.show_rag(labels, g, p1)

# In[35]:

plt.figure()
out = color.label2rgb(labels2, p1)
plt.imshow(out)

# In[38]:

p2 = np.load('0172ML0009240000104879E01_DRLX.npy', allow_pickle=True)
p2 = np.delete(p2, 0, 0)
p2.shape

# In[39]:
コード例 #14
0
ファイル: dist.py プロジェクト: jmorys/EC_rainbow
flat = np.ma.MaskedArray(flat, mask)

plt.figure(dpi=800)
plt.imshow(flat)
io.show()


edges = filters.sobel(flat)
edges_rgb = color.gray2rgb(edges)
from skimage.future import graph
plt.figure(dpi=800)
g = graph.rag_boundary(flat, edges, connectivity=1)
g.remove_node(0)

lc = graph.show_rag(flat, g, edges_rgb, img_cmap=None, edge_cmap='viridis',
                    edge_width=1.2)

plt.colorbar(lc, fraction=0.03)
plt.show()

for i in range(1, len(uni)):
    print([uni[x] for x in g.neighbors(i)])

# plt.figure(dpi=500)
# plt.scatter(cols[rpos, 0], cols[rpos,1])
# plt.grid(True)
# plt.show()



コード例 #15
0
from skimage import data, segmentation
from skimage.future import graph
import matplotlib.pyplot as plt

img = data.coffee()
labels = segmentation.slic(img)
g = graph.rag_mean_color(img, labels)
lc = graph.show_rag(labels, g, img)
cbar = plt.colorbar(lc)
plt.show()
コード例 #16
0
ファイル: regionboundary.py プロジェクト: luizvigiato/python
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Fri Apr  7 10:13:38 2017

@author: luiz
"""

from skimage.future import graph
from skimage import data, segmentation, color, filters, io
from matplotlib import pyplot as plt


img = data.coffee()
gimg = color.rgb2gray(img)

labels = segmentation.slic(img, compactness=30, n_segments=400)
edges = filters.sobel(gimg)
edges_rgb = color.gray2rgb(edges)

g = graph.rag_boundary(labels, edges)
lc = graph.show_rag(labels, g, edges_rgb, img_cmap=None, edge_cmap='viridis',
                    edge_width=1.2)

plt.colorbar(lc, fraction=0.03)
io.show()
コード例 #17
0
g = graph.rag_mean_color(p1, segments)

# In[9]:

labels2 = graph.merge_hierarchical(segments,
                                   g,
                                   thresh=0.05,
                                   rag_copy=True,
                                   in_place_merge=True,
                                   merge_func=merge_mean_color,
                                   weight_func=_weight_mean_color)

# In[10]:

graph.show_rag(segments, g, p1)

# In[11]:

plt.figure()
out = color.label2rgb(labels2, p1)
plt.imshow(out)

# In[12]:

p2 = np.load('0172ML0009240000104879E01_DRLX.npy', allow_pickle=True)
p2 = np.delete(p2, 0, 0)
p2.shape

# In[13]:
コード例 #18
0
if PLOTS_ON:
    out_seg = color.label2rgb(segments, img, kind='avg')
    out_seg_bound = segmentation.mark_boundaries(out_seg, segments, (0, 0, 0))
    out_clust = color.label2rgb(labels, img, kind='avg')
    fig, ax = plt.subplots(nrows=1,
                           ncols=3,
                           sharex=True,
                           sharey=True,
                           figsize=(15, 5))
    ax[0].imshow(out_seg)
    ax[0].set_title('Oversegmentation', fontsize=15)
    ax1 = graph.show_rag(segments,
                         g,
                         img,
                         border_color=None,
                         img_cmap='gray',
                         edge_cmap='magma',
                         ax=ax[1])
    # plt.colorbar(ax1, ax=ax[1])
    ax[1].set_title('Region Adjacency Graph', fontsize=15)
    ax[2].imshow(out_clust)
    ax[2].set_title('MinCutPool', fontsize=15)
    for a in ax:
        a.axis('off')
    plt.tight_layout()
    plt.show()

    # segments = segmentation.felzenszwalb(img, scale=50, sigma=1.5, min_size=50)
    # out_seg = color.label2rgb(segments, img, kind='avg')
    # plt.imshow(out_seg)
from skimage.future import graph
from skimage import segmentation, color, filters, io
from matplotlib import pyplot as plt

img = io.imread("images/sample.jpg")
gimg = color.rgb2gray(img)

labels = segmentation.slic(img, compactness=25, n_segments=800, start_label=1)
edges = filters.sobel(gimg)
edges_rgb = color.gray2rgb(edges)

g = graph.rag_boundary(labels, edges)
lc = graph.show_rag(labels,
                    g,
                    edges_rgb,
                    img_cmap=None,
                    edge_cmap='viridis',
                    edge_width=1.1)

plt.colorbar(lc, fraction=0.03)
io.show()
コード例 #20
0
ファイル: skimage_demonstration.py プロジェクト: myu21/CS550
image2 = resize(image2, (200, 200))  # resize image to fit axis
image2 = swirl(image2, rotation=0, strength=10, radius=90)  # swirling image2

fig, ax1 = plt.subplots()  # creates plot
ax1.imshow(image2, cmap=plt.cm.gray,
           interpolation='none')  # displaying image on plot
ax1.axis('off')  # removing axis and labels
plt.show()  # displaying whole piece

#-------------------------------------------------------------------------------------------------

# Example 3 - Creating region boundries around a photo of a cat

from skimage.future import graph
from skimage import segmentation, color, filters, io

image3 = mpimg.imread("cat.jpg")  # import photo as NumPy array
imagegray = color.rgb2gray(image3)  # converts photo to grayscale

outline = segmentation.slic(
    image3, compactness=50,
    n_segments=1000)  # takes grayscaled image and outlines it
imagecolor = color.gray2rgb(
    imagegray
)  # converts grayscale image to colored (based on intensity of brightness and darkness)

g = graph.rag_boundary(outline, imagegray)  # combined graphic broundries
lc = graph.show_rag(
    outline, g, imagecolor, img_cmap=None, edge_cmap='viridis', edge_width=1
)  # graph itself combining color with outline, creating colored outline
io.show()  # display
コード例 #21
0
from skimage import io, segmentation
from skimage.future import graph
from matplotlib import pyplot as plt

img = io.imread("images/sample.jpg")
labels = segmentation.slic(img, compactness=30, n_segments=400, start_label=1)
g = graph.rag_mean_color(img, labels)

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

ax[0].set_title('RAG drawn with default settings')
lc = graph.show_rag(labels, g, img, ax=ax[0])
# specify the fraction of the plot area that will be used to draw the colorbar
fig.colorbar(lc, fraction=0.03, ax=ax[0])

ax[1].set_title('RAG drawn with grayscale image and viridis colormap')
lc = graph.show_rag(labels,
                    g,
                    img,
                    img_cmap='gray',
                    edge_cmap='viridis',
                    ax=ax[1])
fig.colorbar(lc, fraction=0.03, ax=ax[1])

for a in ax:
    a.axis('off')

plt.tight_layout()
plt.show()
コード例 #22
0
ファイル: plot_rag.py プロジェクト: chinglamchoi/skimage
img = data.coffee()

labels = [
    quickshift(img, kernel_size=3, max_dist=6, ratio=0.5),
    slic(img, compactness=30, n_segments=400),
    felzenszwalb(img, scale=100, sigma=0.5, min_size=50)
]
label_rgbs = [color.label2rgb(label, img, kind='avg') for label in labels]
algos = [["Quickshift", "SLIC (K-Means)", "Felzenszwalb"],
         [["Quickshift Before RAG", "Quickshift After RAG"],
          ["SLIC (K-Means) Before RAG", "SLIC (K-Means) After RAG"],
          ["Felzenszwalb Before RAG", "Felzenszwalb After RAG"]]]

rags = [graph.rag_mean_color(img, label) for label in labels]
edges_drawn_all = [
    plt.colorbar(graph.show_rag(label, rag, img)).set_label(algo)
    for label, rag, algo in zip(labels, rags, algos[0])
]

for edge_drawn in edges_drawn_all:
    plt.show()

# only display edges with weight > thresh
final_labels = [
    graph.cut_threshold(label, rag, 29) for label, rag in zip(labels, rags)
]
final_label_rgbs = [
    color.label2rgb(final_label, img, kind='avg')
    for final_label in final_labels
]
コード例 #23
0
    }


def merge_boundary(graph, src, dst):
    """Call back called before merging 2 nodes.

    In this case we don't need to do any computation here.
    """
    pass

img = data.coffee()
edges = filters.sobel(color.rgb2gray(img))
labels = segmentation.slic(img, compactness=30, n_segments=400)
g = graph.rag_boundary(labels, edges)

graph.show_rag(labels, g, img)
plt.title('Initial RAG')

labels2 = graph.merge_hierarchical(labels, g, thresh=0.08, rag_copy=False,
                                   in_place_merge=True,
                                   merge_func=merge_boundary,
                                   weight_func=weight_boundary)

graph.show_rag(labels, g, img)
plt.title('RAG after hierarchical merging')

plt.figure()
out = color.label2rgb(labels2, img, kind='avg')
plt.imshow(out)
plt.title('Final segmentation')
コード例 #24
0
 def _apply(self, imgmsg, maskmsg):
     bridge = cv_bridge.CvBridge()
     img = bridge.imgmsg_to_cv2(imgmsg)
     if img.ndim == 2:
         img = gray2rgb(img)
     mask = bridge.imgmsg_to_cv2(maskmsg, desired_encoding='mono8')
     mask = mask.reshape(mask.shape[:2])
     # compute label
     roi = closed_mask_roi(mask)
     roi_labels = masked_slic(img=img[roi],
                              mask=mask[roi],
                              n_segments=20,
                              compactness=30)
     if roi_labels is None:
         return
     labels = np.zeros(mask.shape, dtype=np.int32)
     # labels.fill(-1)  # set bg_label
     labels[roi] = roi_labels
     if self.is_debugging:
         # publish debug slic label
         slic_labelmsg = bridge.cv2_to_imgmsg(labels)
         slic_labelmsg.header = imgmsg.header
         self.pub_slic.publish(slic_labelmsg)
     # compute rag
     g = rag_solidity(labels, connectivity=2)
     if self.is_debugging:
         # publish debug rag drawn image
         if LooseVersion(skimage.__version__) >= '0.13.0':
             fig, ax = plt.subplots(figsize=(img.shape[1] * 0.01,
                                             img.shape[0] * 0.01))
             show_rag(labels, g, img, ax=ax)
             ax.axis('off')
             plt.subplots_adjust(0, 0, 1, 1)
             fig.canvas.draw()
             w, h = fig.canvas.get_width_height()
             rag_img = np.fromstring(fig.canvas.tostring_rgb(),
                                     dtype=np.uint8)
             rag_img.shape = (h, w, 3)
             plt.close()
         else:
             rag_img = draw_rag(labels, g, img)
             rag_img = img_as_uint(rag_img)
         rag_imgmsg = bridge.cv2_to_imgmsg(rag_img.astype(np.uint8),
                                           encoding='rgb8')
         rag_imgmsg.header = imgmsg.header
         self.pub_rag.publish(rag_imgmsg)
     # merge rag with solidity
     merged_labels = merge_hierarchical(labels,
                                        g,
                                        thresh=1,
                                        rag_copy=False,
                                        in_place_merge=True,
                                        merge_func=_solidity_merge_func,
                                        weight_func=_solidity_weight_func)
     merged_labels += 1
     merged_labels[mask == 0] = 0
     merged_labelmsg = bridge.cv2_to_imgmsg(merged_labels.astype(np.int32))
     merged_labelmsg.header = imgmsg.header
     self.pub.publish(merged_labelmsg)
     if self.is_debugging:
         out = label2rgb(merged_labels, img)
         out = (out * 255).astype(np.uint8)
         out_msg = bridge.cv2_to_imgmsg(out, encoding='rgb8')
         out_msg.header = imgmsg.header
         self.pub_label.publish(out_msg)
コード例 #25
0
Drawing Region Adjacency Graphs (RAGs)
======================================

This example constructs a Region Adjacency Graph (RAG) and draws it with
the `rag_draw` method.
"""
from skimage import data, segmentation
from skimage.future import graph
from matplotlib import pyplot as plt


img = data.coffee()
labels = segmentation.slic(img, compactness=30, n_segments=400)
g = graph.rag_mean_color(img, labels)


fig, ax = plt.subplots()
ax.set_title('RAG drawn with default settings')
lc = graph.show_rag(labels, g, img, ax=ax)
# fraction specifies the fraction of the area of the plot that will be used to
# draw the colorbar
plt.colorbar(lc, fraction=0.03)

fig, ax = plt.subplots()
ax.set_title('RAG drawn with grayscale image and viridis colormap')
lc = graph.show_rag(labels, g, img, img_cmap='gray', edge_cmap='viridis',
                    ax=ax)
plt.colorbar(lc, fraction=0.03)

plt.show()