one of the default live wallpapers that came with my phone was a wallpaper that displayed the wave form of music playing in the background in real time. I was wondering how one could go about doing this. It seems I should somehow access the streaming data of the background music and compute the samples in real time, but I have no idea how to get the streaming data. I think I can display the wave form by following this tutorial http://codeidol.com/java/swing/Audio/Build-an-Audio-Waveform-Display/, but I'm not exactly sure how to do it. Help would be greatly appreciated/
There is an Android class called Visualizer that lets you access audio being played http://developer.android.com/reference/android/media/audiofx/Visualizer.html
In addition, since Android is all open source, you can look at how the live wallpaper does it! https://android.googlesource.com/platform/packages/wallpapers/MusicVisualization/
来源：https://stackoverflow.com/questions/6317842/how-to-draw-waveform-of-androids-music-player