title: How do you switch cameras?
body: <p>I have a simple OpenTOK web conferencing application that works well. But my users may have multiple USB cameras and I need to be able to allow them to select a different camera under program control. I know they can go to the top of Chrome and click on the camera Icon, but it would be preferable to have a popup in my web application. I have seen this done but have no clue how to do it. Google has not as of yet yielded any search results either. Does anyone know? I need to switch audio sources as well if that is similar. I only care about Chrome for now. </p>
  
  <p>Thanks!</p>