Overlay an image segmentation with Numpy and Matplotlib

To overlay an image segmentation with numpy, we can take the following Steps −

• Make a masked array of 10×10 dimension.

• Update the masked array with 1 for some region.

• Make image data using numpy.

• Mask an array where a condition is met, to get the masked data.

• Create a new figure or activate an existing figure using figure() mrthod.

• Use imshow() method to display data as an image, i.e., on a 2D regular raster.

• To display the figure, use show() method.

Example

from matplotlib import pyplot as plt import numpy as np plt.rcParams["figure.figsize"] = [7.00, 3.50] plt.rcParams["figure.autolayout"] = True mask = np.zeros((10, 10)) mask[3:-3, 3:-3] = 1 im = mask + np.random.randn(10, 10) * 0.01 masked = np.ma.masked_where(mask == 0, mask) plt.figure() plt.subplot(1, 2, 1) plt.imshow(im, 'gray', interpolation='none') plt.subplot(1, 2, 2) plt.imshow(im, 'gray', interpolation='none') plt.imshow(masked, 'jet', interpolation='none', alpha=0.7) plt.show()

Output