title: Cropping image by the center
body: <p>I have a PNG image of size 218, 178. I am using matplotlib's function imread to convert it into a ndarray. I would like to crop it to get the middle 64X64 part of the image. </p>
  
  <p>I tried cropping with np.reshape, but it makes no sense. I also tried slicing as a normal array, but I can't get it right since the actual array has a shape of (218,178,3). I want it (64,64,3) taking from 77 to 141 and 57 to 121 for the first two dimensions.  </p>