The performance of real-time video over wireless ad hoc networks is evaluated based on a novel real-time hardware in the loop test bed. The supporting capabilities of different ad hoc routing protocols and two common video coding algorithms are compared. Results show that the video packet delivery ratios of different routing protocols have similar trends of approximate linear descending with the increase of hop count after certain thresholds. The real-time video quality at more than 4-hop distance, where the packet delivery ratio is less than 75%, cannot be accepted. MPEG-2 can provide real-time video service within 3 hops, while the Motion JPEG cannot support multi-hop real-time video transport. The packet delivery ratio and the decoded block ratio, got with MPEG-2 has an average increase of 55.7% and 205.6%, compared with the results got with motion JPEG, respectively.