git.sesse.net Git - c64tapwav/blob - decode.cpp

   1 // Copyright Steinar H. Gunderson <sgunderson@bigfoot.com>
   2 // Licensed under the GPL, v2. (See the file COPYING.)
   3
   4 #include <stdio.h>
   5 #include <string.h>
   6 #include <math.h>
   7 #include <assert.h>
   8 #include <limits.h>
   9 #include <getopt.h>
  10 #include <vector>
  11 #include <algorithm>
  12
  13 #include "audioreader.h"
  14 #include "interpolate.h"
  15 #include "level.h"
  16 #include "tap.h"
  17 #include "filter.h"
  18
  19 #define BUFSIZE 4096
  20 #define C64_FREQUENCY 985248
  21 #define SYNC_PULSE_START 1000
  22 #define SYNC_PULSE_END 20000
  23 #define SYNC_PULSE_LENGTH 378.0
  24 #define SYNC_TEST_TOLERANCE 1.10
  25
  26 // SPSA options
  27 #define NUM_FILTER_COEFF 32
  28 #define NUM_ITER 5000
  29 #define A NUM_ITER/10  // approx
  30 #define INITIAL_A 0.005 // A bit of trial and error...
  31 #define INITIAL_C 0.02  // This too.
  32 #define GAMMA 0.166
  33 #define ALPHA 1.0
  34
  35 static float hysteresis_limit = 3000.0 / 32768.0;
  36 static bool do_calibrate = true;
  37 static bool output_cycles_plot = false;
  38 static bool do_crop = false;
  39 static float crop_start = 0.0f, crop_end = HUGE_VAL;
  40
  41 static bool use_fir_filter = false;
  42 static float filter_coeff[NUM_FILTER_COEFF] = { 1.0f };  // The rest is filled with 0.
  43 static bool use_rc_filter = false;
  44 static float rc_filter_freq;
  45 static bool output_filtered = false;
  46
  47 static bool quiet = false;
  48 static bool do_auto_level = false;
  49 static bool output_leveled = false;
  50 static std::vector<float> train_snap_points;
  51 static bool do_train = false;
  52
  53 // The minimum estimated sound level (for do_auto_level) at any given point.
  54 // If you decrease this, you'll be able to amplify really silent signals
  55 // by more, but you'll also increase the level of silent (ie. noise-only) segments,
  56 // possibly caused misdetected pulses in these segments.
  57 static float min_level = 0.05f;
  58
  59 // between [x,x+1]
  60 double find_zerocrossing(const std::vector<float> &pcm, int x)
  61 {
  62         if (pcm[x] == 0) {
  63                 return x;
  64         }
  65         if (pcm[x + 1] == 0) {
  66                 return x + 1;
  67         }
  68
  69         assert(pcm[x + 1] < 0);
  70         assert(pcm[x] > 0);
  71
  72         double upper = x;
  73         double lower = x + 1;
  74         while (lower - upper > 1e-3) {
  75                 double mid = 0.5f * (upper + lower);
  76                 if (lanczos_interpolate(pcm, mid) > 0) {
  77                         upper = mid;
  78                 } else {
  79                         lower = mid;
  80                 }
  81         }
  82
  83         return 0.5f * (upper + lower);
  84 }
  85
  86 struct pulse {
  87         double time;  // in seconds from start
  88         double len;   // in seconds
  89 };
  90
  91 // Calibrate on the first ~25k pulses (skip a few, just to be sure).
  92 double calibrate(const std::vector<pulse> &pulses) {
  93         if (pulses.size() < SYNC_PULSE_END) {
  94                 fprintf(stderr, "Too few pulses, not calibrating!\n");
  95                 return 1.0;
  96         }
  97
  98         int sync_pulse_end = -1;
  99         double sync_pulse_stddev = -1.0;
 100
 101         // Compute the standard deviation (to check for uneven speeds).
 102         // If it suddenly skyrockets, we assume that sync ended earlier
 103         // than we thought (it should be 25000 cycles), and that we should
 104         // calibrate on fewer cycles.
 105         for (int try_end : { 2000, 4000, 5000, 7500, 10000, 15000, SYNC_PULSE_END }) {
 106                 double sum2 = 0.0;
 107                 for (int i = SYNC_PULSE_START; i < try_end; ++i) {
 108                         double cycles = pulses[i].len * C64_FREQUENCY;
 109                         sum2 += (cycles - SYNC_PULSE_LENGTH) * (cycles - SYNC_PULSE_LENGTH);
 110                 }
 111                 double stddev = sqrt(sum2 / (try_end - SYNC_PULSE_START - 1));
 112                 if (sync_pulse_end != -1 && stddev > 5.0 && stddev / sync_pulse_stddev > 1.3) {
 113                         fprintf(stderr, "Stopping at %d sync pulses because standard deviation would be too big (%.2f cycles); shorter-than-usual trailer?\n",
 114                                 sync_pulse_end, stddev);
 115                         break;
 116                 }
 117                 sync_pulse_end = try_end;
 118                 sync_pulse_stddev = stddev;
 119         }
 120         if (!quiet) {
 121                 fprintf(stderr, "Sync pulse length standard deviation: %.2f cycles\n",
 122                         sync_pulse_stddev);
 123         }
 124
 125         double sum = 0.0;
 126         for (int i = SYNC_PULSE_START; i < sync_pulse_end; ++i) {
 127                 sum += pulses[i].len;
 128         }
 129         double mean_length = C64_FREQUENCY * sum / (sync_pulse_end - SYNC_PULSE_START);
 130         double calibration_factor = SYNC_PULSE_LENGTH / mean_length;
 131         if (!quiet) {
 132                 fprintf(stderr, "Calibrated sync pulse length: %.2f -> %.2f (change %+.2f%%)\n",
 133                         mean_length, SYNC_PULSE_LENGTH, 100.0 * (calibration_factor - 1.0));
 134         }
 135
 136         // Check for pulses outside +/- 10% (sign of misdetection).
 137         for (int i = SYNC_PULSE_START; i < sync_pulse_end; ++i) {
 138                 double cycles = pulses[i].len * calibration_factor * C64_FREQUENCY;
 139                 if (cycles < SYNC_PULSE_LENGTH / SYNC_TEST_TOLERANCE || cycles > SYNC_PULSE_LENGTH * SYNC_TEST_TOLERANCE) {
 140                         fprintf(stderr, "Sync cycle with downflank at %.6f was detected at %.0f cycles; misdetect?\n",
 141                                 pulses[i].time, cycles);
 142                 }
 143         }
 144
 145         return calibration_factor;
 146 }
 147
 148 void output_tap(const std::vector<pulse>& pulses, double calibration_factor)
 149 {
 150         std::vector<char> tap_data;
 151         for (unsigned i = 0; i < pulses.size(); ++i) {
 152                 double cycles = pulses[i].len * calibration_factor * C64_FREQUENCY;
 153                 int len = lrintf(cycles / TAP_RESOLUTION);
 154                 if (i > SYNC_PULSE_END && (cycles < 100 || cycles > 800)) {
 155                         fprintf(stderr, "Cycle with downflank at %.6f was detected at %.0f cycles; misdetect?\n",
 156                                         pulses[i].time, cycles);
 157                 }
 158                 if (len <= 255) {
 159                         tap_data.push_back(len);
 160                 } else {
 161                         int overflow_len = lrintf(cycles);
 162                         tap_data.push_back(0);
 163                         tap_data.push_back(overflow_len & 0xff);
 164                         tap_data.push_back((overflow_len >> 8) & 0xff);
 165                         tap_data.push_back(overflow_len >> 16);
 166                 }
 167         }
 168
 169         tap_header hdr;
 170         memcpy(hdr.identifier, "C64-TAPE-RAW", 12);
 171         hdr.version = 1;
 172         hdr.reserved[0] = hdr.reserved[1] = hdr.reserved[2] = 0;
 173         hdr.data_len = tap_data.size();
 174
 175         fwrite(&hdr, sizeof(hdr), 1, stdout);
 176         fwrite(tap_data.data(), tap_data.size(), 1, stdout);
 177 }
 178
 179 static struct option long_options[] = {
 180         {"auto-level",       0,                 0, 'a' },
 181         {"output-leveled",   0,                 0, 'A' },
 182         {"no-calibrate",     0,                 0, 's' },
 183         {"plot-cycles",      0,                 0, 'p' },
 184         {"hysteresis-limit", required_argument, 0, 'l' },
 185         {"filter",           required_argument, 0, 'f' },
 186         {"rc-filter",        required_argument, 0, 'r' },
 187         {"output-filtered",  0,                 0, 'F' },
 188         {"crop",             required_argument, 0, 'c' },
 189         {"quiet",            0,                 0, 'q' },
 190         {"help",             0,                 0, 'h' },
 191         {0,                  0,                 0, 0   }
 192 };
 193
 194 void help()
 195 {
 196         fprintf(stderr, "decode [OPTIONS] AUDIO-FILE > TAP-FILE\n");
 197         fprintf(stderr, "\n");
 198         fprintf(stderr, "  -a, --auto-level             automatically adjust amplitude levels throughout the file\n");
 199         fprintf(stderr, "  -A, --output-leveled         output leveled waveform to leveled.raw\n");
 200         fprintf(stderr, "  -m, --min-level              minimum estimated sound level (0..32768) for --auto-level\n");
 201         fprintf(stderr, "  -s, --no-calibrate           do not try to calibrate on sync pulse length\n");
 202         fprintf(stderr, "  -p, --plot-cycles            output debugging info to cycles.plot\n");
 203         fprintf(stderr, "  -l, --hysteresis-limit VAL   change amplitude threshold for ignoring pulses (0..32768)\n");
 204         fprintf(stderr, "  -f, --filter C1:C2:C3:...    specify FIR filter (up to %d coefficients)\n", NUM_FILTER_COEFF);
 205         fprintf(stderr, "  -r, --rc-filter FREQ         send signal through a highpass RC filter with given frequency (in Hertz)\n");
 206         fprintf(stderr, "  -F, --output-filtered        output filtered waveform to filtered.raw\n");
 207         fprintf(stderr, "  -c, --crop START[:END]       use only the given part of the file\n");
 208         fprintf(stderr, "  -t, --train LEN1:LEN2:...    train a filter for detecting any of the given number of cycles\n");
 209         fprintf(stderr, "                               (implies --no-calibrate and --quiet unless overridden)\n");
 210         fprintf(stderr, "  -q, --quiet                  suppress some informational messages\n");
 211         fprintf(stderr, "  -h, --help                   display this help, then exit\n");
 212         exit(1);
 213 }
 214
 215 void parse_options(int argc, char **argv)
 216 {
 217         for ( ;; ) {
 218                 int option_index = 0;
 219                 int c = getopt_long(argc, argv, "aAm:spl:f:r:Fc:t:qh", long_options, &option_index);
 220                 if (c == -1)
 221                         break;
 222
 223                 switch (c) {
 224                 case 'a':
 225                         do_auto_level = true;
 226                         break;
 227
 228                 case 'A':
 229                         output_leveled = true;
 230                         break;
 231
 232                 case 'm':
 233                         min_level = atof(optarg) / 32768.0;
 234                         break;
 235
 236                 case 's':
 237                         do_calibrate = false;
 238                         break;
 239
 240                 case 'p':
 241                         output_cycles_plot = true;
 242                         break;
 243
 244                 case 'l':
 245                         hysteresis_limit = atof(optarg) / 32768.0;
 246                         break;
 247
 248                 case 'f': {
 249                         const char *coeffstr = strtok(optarg, ": ");
 250                         int coeff_index = 0;
 251                         while (coeff_index < NUM_FILTER_COEFF && coeffstr != NULL) {
 252                                 filter_coeff[coeff_index++] = atof(coeffstr);
 253                                 coeffstr = strtok(NULL, ": ");
 254                         }
 255                         use_fir_filter = true;
 256                         break;
 257                 }
 258
 259                 case 'r':
 260                         use_rc_filter = true;
 261                         rc_filter_freq = atof(optarg);
 262                         break;
 263
 264                 case 'F':
 265                         output_filtered = true;
 266                         break;
 267
 268                 case 'c': {
 269                         const char *cropstr = strtok(optarg, ":");
 270                         crop_start = atof(cropstr);
 271                         cropstr = strtok(NULL, ":");
 272                         if (cropstr == NULL) {
 273                                 crop_end = HUGE_VAL;
 274                         } else {
 275                                 crop_end = atof(cropstr);
 276                         }
 277                         do_crop = true;
 278                         break;
 279                 }
 280
 281                 case 't': {
 282                         const char *cyclestr = strtok(optarg, ":");
 283                         while (cyclestr != NULL) {
 284                                 train_snap_points.push_back(atof(cyclestr));
 285                                 cyclestr = strtok(NULL, ":");
 286                         }
 287                         do_train = true;
 288
 289                         // Set reasonable defaults (can be overridden later on the command line).
 290                         do_calibrate = false;
 291                         quiet = true;
 292                         break;
 293                 }
 294
 295                 case 'q':
 296                         quiet = true;
 297                         break;
 298
 299                 case 'h':
 300                 default:
 301                         help();
 302                         exit(1);
 303                 }
 304         }
 305 }
 306
 307 std::vector<float> crop(const std::vector<float>& pcm, float crop_start, float crop_end, int sample_rate)
 308 {
 309         size_t start_sample, end_sample;
 310         if (crop_start >= 0.0f) {
 311                 start_sample = std::min<size_t>(lrintf(crop_start * sample_rate), pcm.size());
 312         }
 313         if (crop_end >= 0.0f) {
 314                 end_sample = std::min<size_t>(lrintf(crop_end * sample_rate), pcm.size());
 315         }
 316         return std::vector<float>(pcm.begin() + start_sample, pcm.begin() + end_sample);
 317 }
 318
 319 // TODO: Support AVX here.
 320 std::vector<float> do_fir_filter(const std::vector<float>& pcm, const float* filter)
 321 {
 322         std::vector<float> filtered_pcm;
 323         filtered_pcm.reserve(pcm.size());
 324         for (unsigned i = NUM_FILTER_COEFF; i < pcm.size(); ++i) {
 325                 float s = 0.0f;
 326                 for (int j = 0; j < NUM_FILTER_COEFF; ++j) {
 327                         s += filter[j] * pcm[i - j];
 328                 }
 329                 filtered_pcm.push_back(s);
 330         }
 331
 332         if (output_filtered) {
 333                 FILE *fp = fopen("filtered.raw", "wb");
 334                 fwrite(filtered_pcm.data(), filtered_pcm.size() * sizeof(filtered_pcm[0]), 1, fp);
 335                 fclose(fp);
 336         }
 337
 338         return filtered_pcm;
 339 }
 340
 341 std::vector<float> do_rc_filter(const std::vector<float>& pcm, float freq, int sample_rate)
 342 {
 343         // This is only a 6 dB/oct filter, which seemingly works better
 344         // than the Filter class, which is a standard biquad (12 dB/oct).
 345         // The b/c calculations come from libnyquist (atone.c);
 346         // I haven't checked, but I suppose they fall out of the bilinear
 347         // transform of the transfer function H(s) = s/(s + w).
 348         std::vector<float> filtered_pcm;
 349         filtered_pcm.resize(pcm.size());
 350         const float b = 2.0f - cos(2.0 * M_PI * freq / sample_rate);
 351         const float c = b - sqrt(b * b - 1.0f);
 352         float prev_in = 0.0f;
 353         float prev_out = 0.0f;
 354         for (unsigned i = 0; i < pcm.size(); ++i) {
 355                 float in = pcm[i];
 356                 float out = c * (prev_out + in - prev_in);
 357                 filtered_pcm[i] = out;
 358                 prev_in = in;
 359                 prev_out = out;
 360         }
 361
 362         if (output_filtered) {
 363                 FILE *fp = fopen("filtered.raw", "wb");
 364                 fwrite(filtered_pcm.data(), filtered_pcm.size() * sizeof(filtered_pcm[0]), 1, fp);
 365                 fclose(fp);
 366         }
 367
 368         return filtered_pcm;
 369 }
 370
 371 std::vector<pulse> detect_pulses(const std::vector<float> &pcm, int sample_rate)
 372 {
 373         std::vector<pulse> pulses;
 374
 375         // Find the flanks.
 376         int last_bit = -1;
 377         double last_downflank = -1;
 378         for (unsigned i = 0; i < pcm.size(); ++i) {
 379                 int bit = (pcm[i] > 0) ? 1 : 0;
 380                 if (bit == 0 && last_bit == 1) {
 381                         // Check if we ever go up above <hysteresis_limit> before we dip down again.
 382                         bool true_pulse = false;
 383                         unsigned j;
 384                         int min_level_after = 32767;
 385                         for (j = i; j < pcm.size(); ++j) {
 386                                 min_level_after = std::min<int>(min_level_after, pcm[j]);
 387                                 if (pcm[j] > 0) break;
 388                                 if (pcm[j] < -hysteresis_limit) {
 389                                         true_pulse = true;
 390                                         break;
 391                                 }
 392                         }
 393
 394                         if (!true_pulse) {
 395 #if 0
 396                                 fprintf(stderr, "Ignored down-flank at %.6f seconds due to hysteresis (%d < %d).\n",
 397                                         double(i) / sample_rate, -min_level_after, hysteresis_limit);
 398 #endif
 399                                 i = j;
 400                                 continue;
 401                         }
 402
 403                         // down-flank!
 404                         double t = find_zerocrossing(pcm, i - 1) * (1.0 / sample_rate) + crop_start;
 405                         if (last_downflank > 0) {
 406                                 pulse p;
 407                                 p.time = t;
 408                                 p.len = t - last_downflank;
 409                                 pulses.push_back(p);
 410                         }
 411                         last_downflank = t;
 412                 }
 413                 last_bit = bit;
 414         }
 415         return pulses;
 416 }
 417
 418 void output_cycle_plot(const std::vector<pulse> &pulses, double calibration_factor)
 419 {
 420         FILE *fp = fopen("cycles.plot", "w");
 421         for (unsigned i = 0; i < pulses.size(); ++i) {
 422                 double cycles = pulses[i].len * calibration_factor * C64_FREQUENCY;
 423                 fprintf(fp, "%f %f\n", pulses[i].time, cycles);
 424         }
 425         fclose(fp);
 426 }
 427
 428 std::pair<int, double> find_closest_point(double x, const std::vector<float> &points)
 429 {
 430         int best_point = 0;
 431         double best_dist = (x - points[0]) * (x - points[0]);
 432         for (unsigned j = 1; j < train_snap_points.size(); ++j) {
 433                 double dist = (x - points[j]) * (x - points[j]);
 434                 if (dist < best_dist) {
 435                         best_point = j;
 436                         best_dist = dist;
 437                 }
 438         }
 439         return std::make_pair(best_point, best_dist);
 440 }
 441
 442 float eval_badness(const std::vector<pulse>& pulses, double calibration_factor)
 443 {
 444         double sum_badness = 0.0;
 445         for (unsigned i = 0; i < pulses.size(); ++i) {
 446                 double cycles = pulses[i].len * calibration_factor * C64_FREQUENCY;
 447                 if (cycles > 2000.0) cycles = 2000.0;  // Don't make pauses arbitrarily bad.
 448                 std::pair<int, double> selected_point_and_sq_dist = find_closest_point(cycles, train_snap_points);
 449                 sum_badness += selected_point_and_sq_dist.second;
 450         }
 451         return sqrt(sum_badness / (pulses.size() - 1));
 452 }
 453
 454 void find_kmeans(const std::vector<pulse> &pulses, double calibration_factor, const std::vector<float> &initial_centers)
 455 {
 456         std::vector<float> last_centers = initial_centers;
 457         std::vector<float> sums;
 458         std::vector<float> num;
 459         sums.resize(initial_centers.size());
 460         num.resize(initial_centers.size());
 461         for ( ;; ) {
 462                 for (unsigned i = 0; i < initial_centers.size(); ++i) {
 463                         sums[i] = 0.0f;
 464                         num[i] = 0;
 465                 }
 466                 for (unsigned i = 0; i < pulses.size(); ++i) {
 467                         double cycles = pulses[i].len * calibration_factor * C64_FREQUENCY;
 468                         // Ignore heavy outliers, which are almost always long pauses.
 469                         if (cycles > 2000.0) {
 470                                 continue;
 471                         }
 472                         std::pair<int, double> selected_point_and_sq_dist = find_closest_point(cycles, last_centers);
 473                         int p = selected_point_and_sq_dist.first;
 474                         sums[p] += cycles;
 475                         ++num[p];
 476                 }
 477                 bool any_moved = false;
 478                 for (unsigned i = 0; i < initial_centers.size(); ++i) {
 479                         if (num[i] == 0) {
 480                                 fprintf(stderr, "K-means broke down, can't output new reference training points\n");
 481                                 return;
 482                         }
 483                         float new_center = sums[i] / num[i];
 484                         if (fabs(new_center - last_centers[i]) > 1e-3) {
 485                                 any_moved = true;
 486                         }
 487                         last_centers[i] = new_center;
 488                 }
 489                 if (!any_moved) {
 490                         break;
 491                 }
 492         }
 493         fprintf(stderr, "New reference training points:");
 494         for (unsigned i = 0; i < last_centers.size(); ++i) {
 495                 fprintf(stderr, " %.3f", last_centers[i]);
 496         }
 497         fprintf(stderr, "\n");
 498 }
 499
 500 void spsa_train(const std::vector<float> &pcm, int sample_rate)
 501 {
 502         float filter[NUM_FILTER_COEFF] = { 1.0f };  // The rest is filled with 0.
 503
 504         float start_c = INITIAL_C;
 505         double best_badness = HUGE_VAL;
 506
 507         for (int n = 1; n < NUM_ITER; ++n) {
 508                 float a = INITIAL_A * pow(n + A, -ALPHA);
 509                 float c = start_c * pow(n, -GAMMA);
 510
 511                 // find a random perturbation
 512                 float p[NUM_FILTER_COEFF];
 513                 float filter1[NUM_FILTER_COEFF], filter2[NUM_FILTER_COEFF];
 514                 for (int i = 0; i < NUM_FILTER_COEFF; ++i) {
 515                         p[i] = (rand() % 2) ? 1.0 : -1.0;
 516                         filter1[i] = std::max(std::min(filter[i] - c * p[i], 1.0f), -1.0f);
 517                         filter2[i] = std::max(std::min(filter[i] + c * p[i], 1.0f), -1.0f);
 518                 }
 519
 520                 std::vector<pulse> pulses1 = detect_pulses(do_fir_filter(pcm, filter1), sample_rate);
 521                 std::vector<pulse> pulses2 = detect_pulses(do_fir_filter(pcm, filter2), sample_rate);
 522                 float badness1 = eval_badness(pulses1, 1.0);
 523                 float badness2 = eval_badness(pulses2, 1.0);
 524
 525                 // Find the gradient estimator
 526                 float g[NUM_FILTER_COEFF];
 527                 for (int i = 0; i < NUM_FILTER_COEFF; ++i) {
 528                         g[i] = (badness2 - badness1) / (2.0 * c * p[i]);
 529                         filter[i] -= a * g[i];
 530                         filter[i] = std::max(std::min(filter[i], 1.0f), -1.0f);
 531                 }
 532                 if (badness2 < badness1) {
 533                         std::swap(badness1, badness2);
 534                         std::swap(filter1, filter2);
 535                         std::swap(pulses1, pulses2);
 536                 }
 537                 if (badness1 < best_badness) {
 538                         printf("\nNew best filter (badness=%f):", badness1);
 539                         for (int i = 0; i < NUM_FILTER_COEFF; ++i) {
 540                                 printf(" %.5f", filter1[i]);
 541                         }
 542                         best_badness = badness1;
 543                         printf("\n");
 544
 545                         find_kmeans(pulses1, 1.0, train_snap_points);
 546
 547                         if (output_cycles_plot) {
 548                                 output_cycle_plot(pulses1, 1.0);
 549                         }
 550                 }
 551                 printf("%d ", n);
 552                 fflush(stdout);
 553         }
 554 }
 555
 556 int main(int argc, char **argv)
 557 {
 558         parse_options(argc, argv);
 559
 560         make_lanczos_weight_table();
 561         std::vector<float> pcm;
 562         int sample_rate;
 563         if (!read_audio_file(argv[optind], &pcm, &sample_rate)) {
 564                 exit(1);
 565         }
 566
 567         if (do_crop) {
 568                 pcm = crop(pcm, crop_start, crop_end, sample_rate);
 569         }
 570
 571         if (use_fir_filter) {
 572                 pcm = do_fir_filter(pcm, filter_coeff);
 573         }
 574
 575         if (use_rc_filter) {
 576                 pcm = do_rc_filter(pcm, rc_filter_freq, sample_rate);
 577         }
 578
 579         if (do_auto_level) {
 580                 pcm = level_samples(pcm, min_level, sample_rate);
 581                 if (output_leveled) {
 582                         FILE *fp = fopen("leveled.raw", "wb");
 583                         fwrite(pcm.data(), pcm.size() * sizeof(pcm[0]), 1, fp);
 584                         fclose(fp);
 585                 }
 586         }
 587
 588 #if 0
 589         for (int i = 0; i < LEN; ++i) {
 590                 in[i] += rand() % 10000;
 591         }
 592 #endif
 593
 594 #if 0
 595         for (int i = 0; i < LEN; ++i) {
 596                 printf("%d\n", in[i]);
 597         }
 598 #endif
 599
 600         if (do_train) {
 601                 spsa_train(pcm, sample_rate);
 602                 exit(0);
 603         }
 604
 605         std::vector<pulse> pulses = detect_pulses(pcm, sample_rate);
 606
 607         double calibration_factor = 1.0;
 608         if (do_calibrate) {
 609                 calibration_factor = calibrate(pulses);
 610         }
 611
 612         if (output_cycles_plot) {
 613                 output_cycle_plot(pulses, calibration_factor);
 614         }
 615
 616         output_tap(pulses, calibration_factor);
 617 }