title: Given a streaming video, how to calculate the size(in bytes) of the video that should have been downloaded to play the video till time t
body: <p>I'll try to make myself as clear as possible. I am streaming a video and I'd like to know for each time <code>t</code> in the video, the no. of bytes that should have been loaded in client's machine to play the video from start to time <code>t</code>. I want this info as an array(or some similar data structure) for various values of <code>t</code></p>
  
  <p>I'm trying to achieve this with the help of youtube api but I'm facing some problems. What I did was to load the video from a time and call <code>getVideoStartBytes</code>. It seems correct seeing the youtube api's documentation but the final graph is weird. It looks like a parabola! It's weird because no. of bytes needed at time 25 can't be less than the no. of bytes needed at time 15. </p>
  
  <p><img src="https://i.stack.imgur.com/zOXss.png" alt="enter image description here">
  Earlier I have done bitrate calculation using vlc and the graph comes something like <code>y=x^2</code> which was at least plausible. </p>
  
  <p>Is this some kind of bug in youtube or maybe something else? Please help.</p>