ValueError in skimage.io.imread()

Question

I am getting a (ValueError: Could not find a format to read the specified file in mode 'i') while doing my image processing:

import matplotlib.pyplot as plt
from skimage.color import rgb2gray
from skimage.transform import resize
from skimage.io import imread, imshow
import pandas as pd
import numpy as np
import os
import warnings
warnings.simplefilter('ignore')


%matplotlib inline

p1 = os.listdir("C:/Users/IMA/Documents/ML/image/p1")
p2 = os.listdir("C:/Users/IMA/Documents/ML/image/p2")

limit = 20
p1_image = [None]*limit
j = 0
for i in p1:
    if(j < limit):
        p1_image[j] = imread("C:/Users/IMA/Documents/ML/image/p1/"+i)
        j += 1
    else:
        break

ValueError                                Traceback (most recent call last)
<ipython-input-7-1854baa31099> in <module>
      4 for i in p1:
      5     if(j<limit):
----> 6         p1_image[j]=imread("C:/Users/IMA/Documents/ML/image/p1/"+i)
      7         j+=1
      8     else:

~\anaconda3\lib\site-packages\skimage\io\_io.py in imread(fname, as_gray, plugin, **plugin_args)
     46 
     47     with file_or_url_context(fname) as fname:
---> 48         img = call_plugin('imread', fname, plugin=plugin, **plugin_args)
     49 
     50     if not hasattr(img, 'ndim'):

~\anaconda3\lib\site-packages\skimage\io\manage_plugins.py in call_plugin(kind, *args, **kwargs)
    208                                (plugin, kind))
    209 
--> 210     return func(*args, **kwargs)
    211 
    212 

~\anaconda3\lib\site-packages\skimage\io\_plugins\imageio_plugin.py in imread(*args, **kwargs)
      8 @wraps(imageio_imread)
      9 def imread(*args, **kwargs):
---> 10     return np.asarray(imageio_imread(*args, **kwargs))

~\anaconda3\lib\site-packages\imageio\core\functions.py in imread(uri, format, **kwargs)
    262 
    263     # Get reader and read first
--> 264     reader = read(uri, format, "i", **kwargs)
    265     with reader:
    266         return reader.get_data(0)

~\anaconda3\lib\site-packages\imageio\core\functions.py in get_reader(uri, format, mode, **kwargs)
    180     if format is None:
    181         raise ValueError(
--> 182             "Could not find a format to read the specified file " "in mode %r" % mode
    183         )
    184 

ValueError: Could not find a format to read the specified file in mode 'i'

Answer 1

Most probably you have non-image files in your directory.

• You either move the non-image files to the another directory or you need to specify the image extension.

For instance: using glob to get all png extension files.

import matplotlib.pyplot as plt
from skimage.color import rgb2gray
from skimage.transform import resize
from skimage.io import imread, imshow
import pandas as pd
import numpy as np
import os
from glob import glob
import warnings
warnings.simplefilter('ignore')

path = "C:/Users/IMA/Documents/ML/image/p1/*.png"
p1 = glob(path)
p2 = os.listdir("C:/Users/IMA/Documents/ML/image/p2")

limit = 20
p1_image = [None]*limit
j = 0
for i in p1:
    if j < limit:
        p1_image[j] = imread(i)
        j += 1
    else:
        break