title: Finding the vertical and the horizontal gradients of a image using python
body: <p>I'm just starting off on Image processing in python using Scipy, Numpy, Image libraries. I need to find the gradient field of the image in order to divide the pixels into bins. For that, I calculated the low pass Gaussian filter to reduce pixel by pixel noise. Now, I've to calculate the horizontal and vertical gradients by convolving  2x2 pixel horizontal and vertical masks across the image. </p>
  
  <p>I couldn't find the exact resources for accomplish this..! </p>