void OouraFFT::rdft(int n, int isgn, double * a, int * ip, double * w)
{
int nw, nc;
double xi;
nw = ip[0];
if (n > (nw << 2))
{
nw = n >> 2;
makewt(nw, ip, w);
}
virtual void init(size_t size) override
{
if (_size != size)
{
_ip.resize(2 + static_cast<int>(std::sqrt(static_cast<double>(size))));
_w.resize(size / 2);
_buffer.resize(size);
_size = size;
const int size4 = static_cast<int>(_size) / 4;
makewt(size4, _ip.data(), _w.data());
makect(size4, _ip.data(), _w.data() + size4);
}
}
void init_rdft(int n, int *ip, float *w)
{
int nw,
nc;
void makewt(int nw, int *ip, float *w);
void makect(int nc, int *ip, float *c);
nw = n >> 2;
makewt(nw, ip, w);
nc = n >> 2;
makect(nc, ip, w + nw);
return;
}
int lsx_rdft_init(int n, FFTcontext* z)
{
int nw;
z->n = n;
z->br = (int*) _aligned_malloc(dft_br_len(n) * sizeof(int), 16);
z->sc = (double*) _aligned_malloc(dft_sc_len(n) * sizeof(double), 16);
if(z->br == NULL || z->sc == NULL)
{
lsx_rdft_close(z);
return -1;
}
nw = n >> 2;
makebr(nw, z->br);
makewt(nw, z->br, z->sc);
makect(nw, z->sc + nw);
makebr(n, z->br);
return 0;
}
