Add 2 variants 256 and 512 FFT (defined by FFT_SIZE from common.hpp)
Not need use 512 FFT for 201 points, possibly use 256 FFT
no any depend from lowpass for data size (offset and window_size), only
float w = kaiser_window(i + offset, window_size, beta);
Made FFT optimization
Add 2 variants 256 and 512 FFT (defined by FFT_SIZE from common.hpp) Not need use 512 FFT for 201 points, possibly use 256 FFT no any depend from lowpass for data size (offset and window_size), only float w = kaiser_window(i + offset, window_size, beta);