In this paper, we consider the problem of streaming video information on lossy packet networks with path and source diversity, such as wireless mesh networks or more generally overlay architectures. We propose to distribute the video information between several streaming servers and to implement network coding in the forwarding peers in order to increase the quality of the video decoded by the streaming client. A network coding algorithm based on Raptor codes permits to combine video packets in the network nodes and to increase the symbol diversity in the network. Coupled with the path diversity in the overlay network, this solution is shown to offer a significant gain in video quality compared to baseline streaming solutions when loss rate becomes important or the network diversity is reduced.