With the growing of multimedia applications, requirement for embedded multimedia systems becomes popular. In this paper we design and implement an embedded 4-channet real-time video and audio coding system (VACS). To achieve real-time coding of4-channel video and audio, we optimize the coding software at algorithm, system and code level. Experimental results of VACS indicate that it works efficiently. Furthermore, since the hardware framework of VACS is based on programmable devices (DSP and FPGA), consequently by realizing diverse multimedia processing algorithms, VACS can also satisfy the requirement of some other embedded multimedia applications.