[javascript] How to detect when a youtube video finishes playing?

I am working on a site that has a ton of embedded youtube videos, the client wants to show a popup whenever a video stops splaying.

I looked at the youtube api and there seems to be a way to detect when a video ends:

http://code.google.com/apis/youtube/js_api_reference.html

but I can't embed the videos like they mentioned on that page since the videos are all already on the site (thousands that have been added manually by pasting embed code).

Is there a way to detect the ending of these videos without changing any of the existing videos (using javascript)?

What you may want to do is include a script on all pages that does the following ... 1. find the youtube-iframe : searching for it by width and height by title or by finding www.youtube.com in its source. You can do that by ... - looping through the window.frames by a for-in loop and then filter out by the properties

1. inject jscript in the iframe of the current page adding the onYoutubePlayerReady must-include-function http://shazwazza.com/post/Injecting-JavaScript-into-other-frames.aspx

2. Add the event listeners etc..

Hope this helps