| 50 | */ |
| 51 | template <typename T> |
| 52 | void rdft_1d_step(const T *src_ptr, size_t N, T *dst_ptr, size_t K) |
| 53 | { |
| 54 | #if defined(_OPENMP) |
| 55 | #pragma omp parallel for |
| 56 | #endif /* _OPENMP */ |
| 57 | for (unsigned int k = 0; k < K; ++k) |
| 58 | { |
| 59 | float Xr = 0; |
| 60 | float Xi = 0; |
| 61 | for (unsigned int n = 0; n < N; ++n) |
| 62 | { |
| 63 | const float alpha = (2 * M_PI * k * n) / N; |
| 64 | const float val_r = src_ptr[n]; |
| 65 | // Assuming DFT from the R domain thus skipping imaginary calculations |
| 66 | Xr += val_r * cos(alpha); |
| 67 | Xi -= val_r * sin(alpha); |
| 68 | } |
| 69 | |
| 70 | dst_ptr[k * 2] = Xr; |
| 71 | dst_ptr[k * 2 + 1] = Xi; |
| 72 | } |
| 73 | } |
| 74 | |
| 75 | /** Performs an one dimensional DFT on a given complex sequence. |
| 76 | * |
no test coverage detected