title: How to find the alpha channel transparency value of a pixel in a png image?
body: <p>I have an image that has alpha channel transparency.</p>
  
  <p>I want to recreate the same background color with RGBA values in CSS but I can not find the real color of the background pixels and their alpha channel value. if I use any sort of color picker it will give me the absolute value of the pixel color which is relevant to its background color. </p>
  
  <p>Do you know any trick to find out the real alpha channel value of a pixel? </p>