| 30 | #define L2SC (float)3.32192809488736218171 |
| 31 | |
| 32 | PitchDetector::PitchDetector() |
| 33 | { |
| 34 | mfs = gSampleRate; |
| 35 | |
| 36 | mcbsize = 2048; |
| 37 | mcorrsize = mcbsize / 2 + 1; |
| 38 | |
| 39 | mpmax = 1 / (float)70; // max and min periods (ms) |
| 40 | mpmin = 1 / (float)700; // eventually may want to bring these out as sliders |
| 41 | |
| 42 | mnmax = (unsigned long)(gSampleRate * mpmax); |
| 43 | if (mnmax > mcorrsize) |
| 44 | { |
| 45 | mnmax = mcorrsize; |
| 46 | } |
| 47 | mnmin = (unsigned long)(gSampleRate * mpmin); |
| 48 | |
| 49 | mcbi = (float*)calloc(mcbsize, sizeof(float)); |
| 50 | |
| 51 | mcbiwr = 0; |
| 52 | |
| 53 | // Generate a window with a single raised cosine from N/4 to 3N/4 |
| 54 | mcbwindow = (float*)calloc(mcbsize, sizeof(float)); |
| 55 | for (int ti = 0; ti < (mcbsize / 2); ti++) |
| 56 | { |
| 57 | mcbwindow[ti + mcbsize / 4] = -0.5 * cos(4 * PI * ti / (mcbsize - 1)) + 0.5; |
| 58 | } |
| 59 | |
| 60 | mnoverlap = 4; |
| 61 | |
| 62 | mFFT = new ::FFT((int)mcbsize); |
| 63 | |
| 64 | mffttime = (float*)calloc(mcbsize, sizeof(float)); |
| 65 | mfftfreqre = (float*)calloc(mcorrsize, sizeof(float)); |
| 66 | mfftfreqim = (float*)calloc(mcorrsize, sizeof(float)); |
| 67 | |
| 68 | |
| 69 | // ---- Calculate autocorrelation of window ---- |
| 70 | macwinv = (float*)calloc(mcbsize, sizeof(float)); |
| 71 | for (int ti = 0; ti < mcbsize; ti++) |
| 72 | { |
| 73 | mffttime[ti] = mcbwindow[ti]; |
| 74 | } |
| 75 | mFFT->Forward(mcbwindow, mfftfreqre, mfftfreqim); |
| 76 | for (int ti = 0; ti < mcorrsize; ti++) |
| 77 | { |
| 78 | mfftfreqre[ti] = (mfftfreqre[ti]) * (mfftfreqre[ti]) + (mfftfreqim[ti]) * (mfftfreqim[ti]); |
| 79 | mfftfreqim[ti] = 0; |
| 80 | } |
| 81 | mFFT->Inverse(mfftfreqre, mfftfreqim, mffttime); |
| 82 | for (long ti = 1; ti < mcbsize; ti++) |
| 83 | { |
| 84 | macwinv[ti] = mffttime[ti] / mffttime[0]; |
| 85 | if (macwinv[ti] > 0.000001) |
| 86 | { |
| 87 | macwinv[ti] = (float)1 / macwinv[ti]; |
| 88 | } |
| 89 | else |