多任务音频播放与实时频谱变换的实现

摘要

使用ARM嵌入式开发实验箱UPTECH2410、μC/OS-Ⅱ多任务调度操作系统和图象显示库系统,设计了一款能在彩色LCD屏上同步显示歌词、音频频谱信息、歌曲点播选单和对应曲目主题画面的可视化MP 3播放器.给出了系统工作流程,讨论了该系统是如何使用双缓冲机制播放和处理音频以保证音频播放的实时性和无缝性,提出一种针对歌曲音频的高效频谱变换方法,并对常见的WAV音乐格式进行了分析.%By using the ARM embedded development box UPTECH2410 and the μC/OS-Ⅱ multi-task scheduling and operating system,and the image display library system,a visual MP3 player is designed,which can synchronously display the lyrics,the audio frequency spectral information,the song request menu and the corresponding song theme pictures on the color LCD screen.The workflow of the whole system is presented, and how to use the double buffering mechanism to play and process the audio to ensure the real-time and seamless audio playback is discussed.A high efficient frequency spectral transform method for the song audio is proposed,and the common WAV musical formats are analyzed.