DSP(Frequency domain) Example

[Sismetic]

Hi, Im trying to do a screen-flashing application, that flashes according to the audio(like 30 times per second), I was recommended looking through DSP, more specifically the Frequency Domain, but I'm not understanding anything, dont know how to implement it. Can anybody show me a practical example of how can I implement it to my code(I already made the music player and know how to flash the screen, what I need is how to tie the flashing with the music at a super velocity, 30 times per second).

Thanks beforehand

[cnoeval]

The human eye can't detect distinct flashing faster than about 30 cycles per second (Hz). At 30Hz you're just going to have a really annoying blur (unless that's the effect you want). Plus, most flat screens these days have a native refresh rate of 60Hz so that will be your upper limit.

[Sismetic]

Ok, then if I want the screen-flashing how many Hz would I need, 10Hz? And if so, how can I do make the screen flash 10 Hz.

PS: Did I explain myself correctly, I mean, do you understand what I mean? Thanks for answering :)