How to handle audio-card buffer

Im trying to do a screen-flashing application that flashes the screen depending on the audio(like an audio visualizer, but instead of a visualization like bars or something like that, just flash the screen).

I already made the music player and know how to make the widget get full screen and change color(which will flash), but I dont know how to detect the (I think it's audio-card)buffer is full, because when it is full I would change the color of the widget, and this would be really super fast, so the screen flashes super quickly. Any ideas on how to detect if the bu开发者_开发知识库ffer is full, or any other approach I might pursue to achieve my goal?

Thanks beforehand.

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Have you checked the SoundMixer Class computeSpectrum method? It doesn't give you a buffer info rather it returns info about the sound being played that you can use in order to represent the sound graphically.