How to get x11 window id of div element rendered in web browser

I need a way to find out the x11 window id of a particular div element inside a web browser( example firefox ) so that this id can be used to display some kind of video streams.

Any way to do this in either c++ or java?

On reading some posts and going through internet, there seemed to be one which used xwininfo. Using this i could only get the window id of the bro开发者_如何学编程wser but was not able to get id for internal elements. Is it possible? If not.. can anyone suggest me any other idea?

Thanks

Where do you need to get the window ID, from an external program separate from the browser, or from JavaScript, or what?

The div isn't going to have its own X window; most likely the only X window is for the entire web page, or in some browsers maybe even for the entire browser window including toolbars.

Perhaps you can write a plugin. A plugin (at least for now, future specs are looking likely to change this) can have its own X window. Flash does for example.