关键词: 嵌入式, 影像交互系统, MPEG-4, 流媒体协议

Abstract:

Within the scope of the wireless local area narrow network bandwidth, it is necessary to compress and decode the original image data for improving the instantaneity and efficiency of image transmission. The image interaction system based on MPEG-4（Moving Pictures Experts Group） video codec technology and streaming media real-time transport protocol uses ARM11 as the core of embedded hardware processor and Linux operating system as the software development platform. The testing result indicates that under the wireless network environment using IEEE 802.11 g standard the network bandwidth is more than 54 Mbit/s, the communication distance in barrierfree line is within a range of 50 meters and the network performance is good. The transmission delay is less than 10 ms and the packet loss rate is less than 0.1% whereas the frame rate is more than 15 frame/s. The image compression ratio of 53.2 ∶1 and the optimal frame quality with the minimum amount of data has been achieved. The size, power consumption and the cost of the system based on embedded processors are much smaller whereas the functionality and the specificity is much better than those in the system based on PC.

Key words: embedded, image interaction system, moving pictures experts group (MPEG-4), streaming media protocol