嵌入式多媒体终端的CPU资源优化分配

在嵌入式平台上实现多媒体通信时,多业务间对有限的运算能力资源的竞争将导致语音通信质量的严重下降。为了解决这一问题,该文提出了利用语音数据流的短时和长时抖动性对其通信质量进行评价的方法,对多种CPU资源分配方案的性能进行了研究,提出了一种能较好的保证语音通信质量的方案,实现了支持语音、静态图像、短信和白板等数据业务并发的手持多媒体通信终端。与其他方案相比,该方案语音数据流的长时抖动性降低了33%。实验证明:通过优先保证实时通信所需要的CPU资源,终端能提供更好质量的多媒体通信。

Optimization of CPU resource assignments on embedded multimedia communication terminals

When multimedia communications are implemented on embedded platforms, the conflicts between multiple services for limited capacity will lead to the degradation of the audio quality. The short-term and long-term jitter of an audio data stream were used to evaluate audio communication quality and the performance of different operational capacity scheduling schemes. A method was developed to provide better audio communication quality in a multimedia communication terminal supporting audio, still images, short messages, a white board, and other data communication processes on an embedded Linux system. The long-term jitter of the scheme was 33% less than other schemes. The method enables terminals to offer better multimedia communication quality by preferentially assigning CPU resources to real-time services.