Displaying image uint8 (0-255) and float (0-1)

Displaying uint8 image 

from skimage import data
img = data.moon()
img

 Out[3]: 
array([[116, 116, 122, ...,  93,  96,  96],
       [116, 116, 122, ...,  93,  96,  96],
       [116, 116, 122, ...,  93,  96,  96],
       ...,
       [109, 109, 112, ..., 117, 116, 116],
       [114, 114, 113, ..., 118, 118, 118],
       [114, 114, 113, ..., 118, 118, 118]], dtype=uint8)

 import matplotlib.pyplot as plt

fig = plt.figure(figsize=(8, 5))


 sub1 = fig.add_subplot(2, 2, 1)

sub1.imshow(img, cmap=plt.cm.gray)
<matplotlib.image.AxesImage at 0x7facb3887410>


sub1.set_title('Displaying image in utin8(0-255)')

Text(0.5,1,u'Displaying image in utin8(0-255)')

Displaying float image 

img_float = img/255.0

img_float

array([[0.45490196, 0.45490196, 0.47843137, ..., 0.36470588, 0.37647059,
        0.37647059],
       [0.45490196, 0.45490196, 0.47843137, ..., 0.36470588, 0.37647059,
        0.37647059],
       [0.45490196, 0.45490196, 0.47843137, ..., 0.36470588, 0.37647059,
        0.37647059],
       ...,
       [0.42745098, 0.42745098, 0.43921569, ..., 0.45882353, 0.45490196,
        0.45490196],
       [0.44705882, 0.44705882, 0.44313725, ..., 0.4627451 , 0.4627451 ,
        0.4627451 ],
       [0.44705882, 0.44705882, 0.44313725, ..., 0.4627451 , 0.4627451 ,
        0.4627451 ]])


sub2 = fig.add_subplot(2, 2, 2)

sub2.imshow(img_float, cmap=plt.cm.gray)
Out[12]: <matplotlib.image.AxesImage at 0x7facb90d5fd0>

sub2.set_title('Displaying image in float(0-1)')
Out[13]: Text(0.5,1,u'Displaying image in float(0-1)')


You may also use img_as_float function from skimage as follows to convert uint8 to float image 

from skimage import img_as_float
image_as_float = img_as_float(img)
img_float == image_as_float
array([[ True,  True,  True, ...,  True,  True,  True],
       [ True,  True,  True, ...,  True,  True,  True],
       [ True,  True,  True, ...,  True,  True,  True],
       ...,
       [ True,  True,  True, ...,  True,  True,  True],
       [ True,  True,  True, ...,  True,  True,  True],
       [ True,  True,  True, ...,  True,  True,  True]])





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