todo

音频编码

- known bug : when recording, converting, and recording a lame_close() call fail
- allow decompression the same way as in the command-line
- allow VBR mode
- allow channel resampling (mono to stereo / stereo to mono)
- allow internal resampling (difference in the format suggestion)
- use global pointers for string
- use the bitrate/freq tables from LAME

/ add the decoding engine