One of the major challenges facing vehicular ad-hoc communication is to ensure efficient services delivery under different network conditions. In this context, video communication is envisioned by the scientific and industrial communities to be of high benefit for traffic management as well as for providing value-added entertainment and advertising services. In this paper, we propose a new protocol for efficient VIdeo streaming over COgnitive radio VANETs (ViCoV), a video streaming solution which broadcasts safety and entrainment content in both fully and intermittently connected networks under different traffic conditions. First, ViCoV selects the best available dedicated or Cognitive Radio (CR) channels to disseminate the content. Then, it carefully choses a minimum sub-set of rebroadcaster nodes to reduce interferences and to achieve high video quality. The CR channels are selected based on their stability over the time, whereas the rebroadcaster nodes are selected based on a new centrality metric, inspired from the Social Network Analysis (SNA), called dissemination capacity. Through simulations, we compared ViCoV with the multichannel vehicular communication standard IEEE 1609.4 and two pioneering video streaming mechanisms over VANET. The performance evaluation shows that ViCoV outperforms the abovementioned mechanisms in terms of providing higher video delivery ratio, lower end-to-end transmission delay and lower frame loss ratio in both fully and intermittently connected networks.