Possibility to get IP Camera stream from url and get frame in Android (mobile) app

I am testing open cv library for android, performing some image manipulation tests. All works fine.
Now i would like to code an Android App in order to:

*get ip camera stream from a URL. I think to use a VideoCapture component
*take a frame from the stream and manipulate it

I tried but the VideoCapture opening fails with the url stream: **VideoCapture vc = new VideoCapture(); **
** vc.open(“”); **

I am not sure if in Android/Java we could have limitations in using external url from external sources. Is it true?

Thank you all,