Android is “the open source revolution” applied to cellular telephony and mobile computing. At least, part of the revolution. There have been many other attempts to provide open source cell phones, most of them largely defunct, ranging from the Open
前言
录音采用的是AudioRecord，通过MediaCodec进行编码，用MediaMuxer合成输出MP4文件。
1.
这里用AudioRecord来得到从麦克风录制的声音，AudiorRecord的用法还是比较简单的，首先初始化AudioRecord
fun prepare(file: File?, outputFormat: Int = MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4, audioSource: Int = MediaRecor
