chris_xieq
Joined: 08 May 2008
Posts: 4
|
 12 May 2008 9:45 Audio FFT analyzer |
|
|
|
Hi guys,
I am currently in the project of audio anlyzer, but I got some problem of audia FFT,
say, I have the raw audio information without any codec from ADC through IIS interface and then, I need to anlyzer the audio quality such THD, witch is realized in FFT, but, in Xilinx or @ltera's core, there should be Real and Image part input, however, the raw audio data doern't.
Can you guys give me some suggestion about this? What kind of siganl process should be done before input to FFT?
Chris,
Regards
|
|
FvM
Joined: 22 Jan 2008
Posts: 2686
Helped: 439
Location: Bochum, Germany
|
| 12 May 2008 15:33 Re: Audio FFT analyzer |
|
|
|
| There is a specific method to increase FFT resource utilization by using real and imaginary part, but as a first step, it's easier to simply zero the imaginary input part. Furthermore, a window function is usually needed when the FFT of a signal cutting is to be analyzed. And a magnitude should be calculated from complex FFT output.
|
|
