code: public RTPFormats negotiateVideo(SessionDescription sdp, RTPFormats formats) {
      	this.video.clean();
      	MediaDescriptorField descriptor = sdp.getVideoDescriptor();
      	descriptor.getFormats().intersection(formats, this.video);
      	return this.video;
      }
docs: Negotiates the video formats to be used in the call.
  @param sdp The session description
  @param formats The available formats
  @return The supported formats. If no formats are supported the returned list will be empty.