Manipulating the exposure of an image

The exposure of an image tells us whether the image is too dark, too light, or balanced. It can be measured with a histogram of the intensity values of all pixels. Improving the exposure of an image is a basic image-editing operation. As we will see in this recipe, it can be done easily with scikit-image.

Getting ready

The scikit-image command should be included by default in Anaconda. Otherwise, you can always install it manually with conda install scikit-image.

How to do it...

1. Let's import the packages:

   >>> import numpy as np
       import matplotlib.pyplot as plt
       import skimage.exposure as skie
       %matplotlib inline

2. We open an image with Matplotlib. We only take a single RGB component to have a grayscale image (it is a very crude way of doing it, we give much better ways at the end of this recipe):

   >>> img = plt.imread('https://github.com/ipython-books/'
                        'cookbook-2nd-data/blob/master/'
                        'beach...