The following ffmpeg command read out is to convert the file into input.wma average bit rate (ab = average bitrate) to 32k output.mp3 file name of the mp3 file.
Of course, you can also specify the sampling rate (sampling rate), the use of ar, should be the average rate and the like.
ffmpeg -i input.wma -ab 64 -ar 22050 output.mp3
Ffmpeg is a command to read out files into input.wma average bit rate of 64kb per second, the sampling rate of the mp3 file 22050hz.
If you turn to make flash mp3 player to play online, then -ar set to a multiple of 11khz, such as 110,252,205,044,100, is what we often say how much kilohertz, the first few are 11khz 22khz 44khz
