Encontre que não sejam imagens na pasta INTERMAGEM.

import matplotlib.image as mpimg

images = []
folder = './your/folder/'
for filename in os.listdir(folder):
    try:
        img = mpimg.imread(os.path.join(folder, filename))
        if img is not None:
            images.append(img)
    except:
        print('Cant import ' + filename)
images = np.asarray(images)
Glorious Gannet