spectrum

I want to generate an audio spectrum (as seen in this video ) of a mp3 audio file. Basically this problem requires calculating the fft of the audio signal. How do I program this in C/C++? I've looked at a couple of open source libraries such as FFTW and I really don't know how to use these for my problem. Any help would be greatly appreciated. Thanks in advance! Paul R There are quite a few similar/related questions on SO already which are well worth reading as the answers contain a lot of useful information and advice, but in essence you need to do this: convert audio data to format required

I am trying to create a graphical spectrum analyzer in python. I am currently reading 1024 bytes of a 16 bit dual channel 44,100 Hz sample rate audio stream and averaging the amplitude of the 2 channels together. So now I have an array of 256 signed shorts. I now want to preform a fft on that array, using a module like numpy, and use the result to create the graphical spectrum analyzer, which, to start will just be 32 bars. I have read the wikipedia articles on Fast Fourier Transform and Discrete Fourier Transform but I am still unclear of what the resulting array represents. This is what the