iOS Question How to get the data of music file to draw waveform

[bagazhou]

HI
on B4i，
I want to play a music file, for example demo.mp3
How to get the data of music file to draw waveform in real time, hope to get some suggestions

in objc ，i can use AVAudioPlayer and averagePowerForChannel ，but on b4i How to do it

thanks