One challenge of adapting network coding for video transmission over an erasure network is the insufficient rank in the Global coefficient matrix (GCM) at the decoder. To reduce the impact of above problem on video transmission, a special design for the global coding matrix of Random linear network coding (RLNC) is proposed to realize reliable video multicast. Rate allocation is also presented to minimize the quality degradation of the video. Simulation results show the method can provide higher reconstructed quality of video compared with traditional store and forward method and conventional RLNC design for video transmission. The method can be applied to video multicast over different type of network such as P2P networks.