Part Number: TMDSEVM6678
Tool/software: Code Composer Studio
Hi,
I´m working with signal processing and I want to work with all core to process FFT and IFFT for some images frames.
I have started with the simple example "fft_example" included at dsplib_c66x_3_1_0_0 dir.
I made some modification and generated a simple sin wave with theses parameters:
Fs = 4000; // Sampling frequency
T = 1/Fs; // Sample time
L = 1024; // Length of signal
freq1 = 100;
generate t[x] = T*x; x = 0 .... L-1
and y[x] = sin(2*pi*freq1*t[x])/((float)1024;
In ccs 5.5 the wave form and the FFT tools fine.
using the same like example
DSP_fft32x32(w_32x32, NPT, in_32x32, out_32x32);
plotting the module of out_32x32 and using the FFT tools, I got some difference. It was supposed to have FFT on 100 Hz thas is correct, but the plot shows 25 Hz
So, if I tried to do DSP_ifft32x32(w_32x32, NPT,out_32x32,in2_32x32);
I will not have the same lke input data.
What kind of mistake i´m doing
best Regards,
Nivaldo
