In order to improve the spectrum utilization in visible light communications (VLC), a new multidimension encoding scheme is proposed and its encoding principle and performance are analysed. A VLC system to transmit high quality video and audio signal is demonstrated. The system uses RGB light emitting diode (LED) as source, which is encoded by the multi-dimension encoding scheme with 16 pulses position modulation (16-PPM) as a base modulation, and achieves the video stream communication in the distance of 3.0 m and at the rate of 1.5 Mbit/s . The results show that the method can take fully the advantage of the vast frequency resources provided by light, improve the channel capacity and provide the possiblity of high-speed communication systems.