API for making video conference calls in Iphone sdk?

Is there any API to make video conferencing 开发者_如何学JAVAcalls in Iphone sdk or any third party tools to make this.Guy's I need some documentation or tutorials to implement the video conferencing calls.

Anyone's suggestion will me much appreciated.

Thanks in advance, Monish.

Here is a suggestion by @Laurent Etiemble in this previous SO question

Take a look at the iDoubs project. It is a full feature SIP/IMS phone with various audio/video capabilities. Note that the project is under GPL license.