title: What is the decoded output of a video codec?
body: <p>Folks,</p>
  
  <p>I am wondering if someone can explain to me what exactly is the output of video decoding. Let's say it is a H.264 stream in an MP4 container.</p>
  
  <p>From displaying something on the screen, I guess decoder can provider two different types of output:</p>
  
  <ol>
  <li>Point - (x, y) coordinate of the location and the (R, G, B) color for the pixel</li>
  <li>Rectangle (x, y, w, h) units for the rectangle and the (R, G, B) color to display</li>
  </ol>
  
  <p>There is also the issue of time stamp.</p>
  
  <p>Can you please enlighten me or point me the right link on what is generated out of a decoder and how a video client can use this information to display something on screen?</p>
  
  <p>I intend to download VideoLAN source and examine it but some explanation would be helpful.</p>
  
  <p>Thank you in advance for your help.</p>
  
  <p>Regards,
  Peter</p>