AVS编码器的EDMA数据存取策略

Data access method of AVS encoder

视频信号传输是视频信号处理系统的关键技术,增强型直接内存存取(EDMA)可独立于CPU进行后台批量数据传输,在数字信号处理器(DSP)中用于快速数据交换。本文提出了在TMS320DM6446 DSP平台上实现AVS视频编码器的过程中,如何使用EDMA优化数据存取的策略,从而减少了DSP耗费在数据搬移上的开销。利用EDMA在CPU后台高效地实现存储空间的数据搬移,并在EDMA中断服务程序中对视频数据信号进行处理,DSP的中央处理单元就能够专注于信号处理和系统功能控制,从而满足视频信号处理系统的高速实时性要求。

Data transmission is t he key technology in video signal processing system.The enhanced Direct Memory Access（EDMA）can transmit data in batch independent of CPU,it is used for fast data transfer in digital signals processor（DSP）.The text introduce how to complete data access in the implement of AVS encoder based on TMS320DM6446 DSP in order to reduce the time consuming of transferring data of which the DSP is in charge.In the video signal processing system,the video data transfers from FIFO memory to DSP were carried out by EDMA channel in the background,and t he video data were processed in EDMA interruption service program.The CPU of DSP can focus on signal processing as well as system real time controls,sot hat the real time requirement of the video signal processing system could be satisfied.