utils/makemhr/loadsofa.cpp

   1 /*
   2  * HRTF utility for producing and demonstrating the process of creating an
   3  * OpenAL Soft compatible HRIR data set.
   4  *
   5  * Copyright (C) 2018-2019  Christopher Fitzgerald
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Or visit:  http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
  22  */
  23
  24 #include "loadsofa.h"
  25
  26 #include <algorithm>
  27 #include <atomic>
  28 #include <chrono>
  29 #include <cmath>
  30 #include <cstdio>
  31 #include <functional>
  32 #include <future>
  33 #include <iterator>
  34 #include <memory>
  35 #include <numeric>
  36 #include <optional>
  37 #include <string>
  38 #include <string_view>
  39 #include <thread>
  40 #include <vector>
  41
  42 #include "alspan.h"
  43 #include "alstring.h"
  44 #include "alnumeric.h"
  45 #include "makemhr.h"
  46 #include "polyphase_resampler.h"
  47 #include "sofa-support.h"
  48
  49 #include "mysofa.h"
  50
  51
  52 namespace {
  53
  54 using namespace std::string_view_literals;
  55 using uint = unsigned int;
  56
  57 /* Attempts to produce a compatible layout.  Most data sets tend to be
  58  * uniform and have the same major axis as used by OpenAL Soft's HRTF model.
  59  * This will remove outliers and produce a maximally dense layout when
  60  * possible.  Those sets that contain purely random measurements or use
  61  * different major axes will fail.
  62  */
  63 auto PrepareLayout(const al::span<const float> xyzs, HrirDataT *hData) -> bool
  64 {
  65     fprintf(stdout, "Detecting compatible layout...\n");
  66
  67     auto fds = GetCompatibleLayout(xyzs);
  68     if(fds.size() > MAX_FD_COUNT)
  69     {
  70         fprintf(stdout, "Incompatible layout (inumerable radii).\n");
  71         return false;
  72     }
  73
  74     std::array<double,MAX_FD_COUNT> distances{};
  75     std::array<uint,MAX_FD_COUNT> evCounts{};
  76     auto azCounts = std::vector<std::array<uint,MAX_EV_COUNT>>(MAX_FD_COUNT);
  77     for(auto &azs : azCounts) azs.fill(0u);
  78
  79     uint fi{0u}, ir_total{0u};
  80     for(const auto &field : fds)
  81     {
  82         distances[fi] = field.mDistance;
  83         evCounts[fi] = field.mEvCount;
  84
  85         for(uint ei{0u};ei < field.mEvStart;ei++)
  86             azCounts[fi][ei] = field.mAzCounts[field.mEvCount-ei-1];
  87         for(uint ei{field.mEvStart};ei < field.mEvCount;ei++)
  88         {
  89             azCounts[fi][ei] = field.mAzCounts[ei];
  90             ir_total += field.mAzCounts[ei];
  91         }
  92
  93         ++fi;
  94     }
  95     fprintf(stdout, "Using %u of %zu IRs.\n", ir_total, xyzs.size()/3);
  96     const auto azs = al::span{azCounts}.first<MAX_FD_COUNT>();
  97     return PrepareHrirData(al::span{distances}.first(fi), evCounts, azs, hData);
  98 }
  99
 100 float GetSampleRate(MYSOFA_HRTF *sofaHrtf)
 101 {
 102     const char *srate_dim{nullptr};
 103     const char *srate_units{nullptr};
 104     MYSOFA_ARRAY *srate_array{&sofaHrtf->DataSamplingRate};
 105     MYSOFA_ATTRIBUTE *srate_attrs{srate_array->attributes};
 106     while(srate_attrs)
 107     {
 108         if("DIMENSION_LIST"sv == srate_attrs->name)
 109         {
 110             if(srate_dim)
 111             {
 112                 fprintf(stderr, "Duplicate SampleRate.DIMENSION_LIST\n");
 113                 return 0.0f;
 114             }
 115             srate_dim = srate_attrs->value;
 116         }
 117         else if("Units"sv == srate_attrs->name)
 118         {
 119             if(srate_units)
 120             {
 121                 fprintf(stderr, "Duplicate SampleRate.Units\n");
 122                 return 0.0f;
 123             }
 124             srate_units = srate_attrs->value;
 125         }
 126         else
 127             fprintf(stderr, "Unexpected sample rate attribute: %s = %s\n", srate_attrs->name,
 128                 srate_attrs->value);
 129         srate_attrs = srate_attrs->next;
 130     }
 131     if(!srate_dim)
 132     {
 133         fprintf(stderr, "Missing sample rate dimensions\n");
 134         return 0.0f;
 135     }
 136     if(srate_dim != "I"sv)
 137     {
 138         fprintf(stderr, "Unsupported sample rate dimensions: %s\n", srate_dim);
 139         return 0.0f;
 140     }
 141     if(!srate_units)
 142     {
 143         fprintf(stderr, "Missing sample rate unit type\n");
 144         return 0.0f;
 145     }
 146     if(srate_units != "hertz"sv)
 147     {
 148         fprintf(stderr, "Unsupported sample rate unit type: %s\n", srate_units);
 149         return 0.0f;
 150     }
 151     /* I dimensions guarantees 1 element, so just extract it. */
 152     const auto values = al::span{srate_array->values, sofaHrtf->I};
 153     if(values[0] < float{MIN_RATE} || values[0] > float{MAX_RATE})
 154     {
 155         fprintf(stderr, "Sample rate out of range: %f (expected %u to %u)", values[0], MIN_RATE,
 156             MAX_RATE);
 157         return 0.0f;
 158     }
 159     return values[0];
 160 }
 161
 162 enum class DelayType : uint8_t {
 163     None,
 164     I_R, /* [1][Channels] */
 165     M_R, /* [HRIRs][Channels] */
 166 };
 167 auto PrepareDelay(MYSOFA_HRTF *sofaHrtf) -> std::optional<DelayType>
 168 {
 169     const char *delay_dim{nullptr};
 170     MYSOFA_ARRAY *delay_array{&sofaHrtf->DataDelay};
 171     MYSOFA_ATTRIBUTE *delay_attrs{delay_array->attributes};
 172     while(delay_attrs)
 173     {
 174         if("DIMENSION_LIST"sv == delay_attrs->name)
 175         {
 176             if(delay_dim)
 177             {
 178                 fprintf(stderr, "Duplicate Delay.DIMENSION_LIST\n");
 179                 return std::nullopt;
 180             }
 181             delay_dim = delay_attrs->value;
 182         }
 183         else
 184             fprintf(stderr, "Unexpected delay attribute: %s = %s\n", delay_attrs->name,
 185                 delay_attrs->value ? delay_attrs->value : "<null>");
 186         delay_attrs = delay_attrs->next;
 187     }
 188     if(!delay_dim)
 189     {
 190         fprintf(stderr, "Missing delay dimensions\n");
 191         return DelayType::None;
 192     }
 193     if(delay_dim == "I,R"sv)
 194         return DelayType::I_R;
 195     if(delay_dim == "M,R"sv)
 196         return DelayType::M_R;
 197
 198     fprintf(stderr, "Unsupported delay dimensions: %s\n", delay_dim);
 199     return std::nullopt;
 200 }
 201
 202 bool CheckIrData(MYSOFA_HRTF *sofaHrtf)
 203 {
 204     const char *ir_dim{nullptr};
 205     MYSOFA_ARRAY *ir_array{&sofaHrtf->DataIR};
 206     MYSOFA_ATTRIBUTE *ir_attrs{ir_array->attributes};
 207     while(ir_attrs)
 208     {
 209         if("DIMENSION_LIST"sv == ir_attrs->name)
 210         {
 211             if(ir_dim)
 212             {
 213                 fprintf(stderr, "Duplicate IR.DIMENSION_LIST\n");
 214                 return false;
 215             }
 216             ir_dim = ir_attrs->value;
 217         }
 218         else
 219             fprintf(stderr, "Unexpected IR attribute: %s = %s\n", ir_attrs->name,
 220                 ir_attrs->value ? ir_attrs->value : "<null>");
 221         ir_attrs = ir_attrs->next;
 222     }
 223     if(!ir_dim)
 224     {
 225         fprintf(stderr, "Missing IR dimensions\n");
 226         return false;
 227     }
 228     if(ir_dim != "M,R,N"sv)
 229     {
 230         fprintf(stderr, "Unsupported IR dimensions: %s\n", ir_dim);
 231         return false;
 232     }
 233     return true;
 234 }
 235
 236
 237 /* Calculate the onset time of a HRIR. */
 238 constexpr int OnsetRateMultiple{10};
 239 auto CalcHrirOnset(PPhaseResampler &rs, const uint rate, al::span<double> upsampled,
 240     const al::span<const double> hrir) -> double
 241 {
 242     rs.process(hrir, upsampled);
 243
 244     auto abs_lt = [](const double lhs, const double rhs) -> bool
 245     { return std::abs(lhs) < std::abs(rhs); };
 246     auto iter = std::max_element(upsampled.cbegin(), upsampled.cend(), abs_lt);
 247     return static_cast<double>(std::distance(upsampled.cbegin(), iter)) /
 248         (double{OnsetRateMultiple}*rate);
 249 }
 250
 251 /* Calculate the magnitude response of a HRIR. */
 252 void CalcHrirMagnitude(const uint points, al::span<complex_d> h, const al::span<double> hrir)
 253 {
 254     auto iter = std::copy_n(hrir.cbegin(), points, h.begin());
 255     std::fill(iter, h.end(), complex_d{0.0, 0.0});
 256
 257     forward_fft(h);
 258     MagnitudeResponse(h, hrir.first((h.size()/2) + 1));
 259 }
 260
 261 bool LoadResponses(MYSOFA_HRTF *sofaHrtf, HrirDataT *hData, const DelayType delayType,
 262     const uint outRate)
 263 {
 264     std::atomic<uint> loaded_count{0u};
 265
 266     auto load_proc = [sofaHrtf,hData,delayType,outRate,&loaded_count]() -> bool
 267     {
 268         const uint channels{(hData->mChannelType == CT_STEREO) ? 2u : 1u};
 269         hData->mHrirsBase.resize(channels * size_t{hData->mIrCount} * hData->mIrSize, 0.0);
 270         const auto hrirs = al::span{hData->mHrirsBase};
 271
 272         std::vector<double> restmp;
 273         std::optional<PPhaseResampler> resampler;
 274         if(outRate && outRate != hData->mIrRate)
 275         {
 276             resampler.emplace().init(hData->mIrRate, outRate);
 277             restmp.resize(sofaHrtf->N);
 278         }
 279
 280         const auto srcPosValues = al::span{sofaHrtf->SourcePosition.values, sofaHrtf->M*3_uz};
 281         const auto irValues = al::span{sofaHrtf->DataIR.values,
 282             size_t{sofaHrtf->M}*sofaHrtf->R*sofaHrtf->N};
 283         for(uint si{0u};si < sofaHrtf->M;++si)
 284         {
 285             loaded_count.fetch_add(1u);
 286
 287             std::array aer{srcPosValues[3_uz*si], srcPosValues[3_uz*si + 1],
 288                 srcPosValues[3_uz*si + 2]};
 289             mysofa_c2s(aer.data());
 290
 291             if(std::abs(aer[1]) >= 89.999f)
 292                 aer[0] = 0.0f;
 293             else
 294                 aer[0] = std::fmod(360.0f - aer[0], 360.0f);
 295
 296             auto field = std::find_if(hData->mFds.cbegin(), hData->mFds.cend(),
 297                 [&aer](const HrirFdT &fld) -> bool
 298                 { return (std::abs(aer[2] - fld.mDistance) < 0.001); });
 299             if(field == hData->mFds.cend())
 300                 continue;
 301
 302             const double evscale{180.0 / static_cast<double>(field->mEvs.size()-1)};
 303             double ef{(90.0 + aer[1]) / evscale};
 304             auto ei = static_cast<uint>(std::round(ef));
 305             ef = (ef - ei) * evscale;
 306             if(std::abs(ef) >= 0.1) continue;
 307
 308             const double azscale{360.0 / static_cast<double>(field->mEvs[ei].mAzs.size())};
 309             double af{aer[0] / azscale};
 310             auto ai = static_cast<uint>(std::round(af));
 311             af = (af-ai) * azscale;
 312             ai %= static_cast<uint>(field->mEvs[ei].mAzs.size());
 313             if(std::abs(af) >= 0.1) continue;
 314
 315             HrirAzT &azd = field->mEvs[ei].mAzs[ai];
 316             if(!azd.mIrs[0].empty())
 317             {
 318                 fprintf(stderr, "\nMultiple measurements near [ a=%f, e=%f, r=%f ].\n",
 319                     aer[0], aer[1], aer[2]);
 320                 return false;
 321             }
 322
 323             for(uint ti{0u};ti < channels;++ti)
 324             {
 325                 azd.mIrs[ti] = hrirs.subspan(
 326                     (size_t{hData->mIrCount}*ti + azd.mIndex) * hData->mIrSize, hData->mIrSize);
 327                 const auto ir = irValues.subspan((size_t{si}*sofaHrtf->R + ti)*sofaHrtf->N,
 328                     sofaHrtf->N);
 329                 if(!resampler)
 330                     std::copy_n(ir.cbegin(), ir.size(), azd.mIrs[ti].begin());
 331                 else
 332                 {
 333                     std::copy_n(ir.cbegin(), ir.size(), restmp.begin());
 334                     resampler->process(restmp, azd.mIrs[ti]);
 335                 }
 336             }
 337
 338             /* Include any per-channel or per-HRIR delays. */
 339             if(delayType == DelayType::I_R)
 340             {
 341                 const auto delayValues = al::span{sofaHrtf->DataDelay.values,
 342                     size_t{sofaHrtf->I}*sofaHrtf->R};
 343                 for(uint ti{0u};ti < channels;++ti)
 344                     azd.mDelays[ti] = delayValues[ti] / static_cast<float>(hData->mIrRate);
 345             }
 346             else if(delayType == DelayType::M_R)
 347             {
 348                 const auto delayValues = al::span{sofaHrtf->DataDelay.values,
 349                     size_t{sofaHrtf->M}*sofaHrtf->R};
 350                 for(uint ti{0u};ti < channels;++ti)
 351                     azd.mDelays[ti] = delayValues[si*sofaHrtf->R + ti] /
 352                         static_cast<float>(hData->mIrRate);
 353             }
 354         }
 355
 356         if(outRate && outRate != hData->mIrRate)
 357         {
 358             const double scale{static_cast<double>(outRate) / hData->mIrRate};
 359             hData->mIrRate = outRate;
 360             hData->mIrPoints = std::min(static_cast<uint>(std::ceil(hData->mIrPoints*scale)),
 361                 hData->mIrSize);
 362         }
 363         return true;
 364     };
 365
 366     std::future_status load_status{};
 367     auto load_future = std::async(std::launch::async, load_proc);
 368     do {
 369         load_status = load_future.wait_for(std::chrono::milliseconds{50});
 370         printf("\rLoading HRIRs... %u of %u", loaded_count.load(), sofaHrtf->M);
 371         fflush(stdout);
 372     } while(load_status != std::future_status::ready);
 373     fputc('\n', stdout);
 374     return load_future.get();
 375 }
 376
 377
 378 /* Calculates the frequency magnitudes of the HRIR set. Work is delegated to
 379  * this struct, which runs asynchronously on one or more threads (sharing the
 380  * same calculator object).
 381  */
 382 struct MagCalculator {
 383     const uint mFftSize{};
 384     const uint mIrPoints{};
 385     std::vector<al::span<double>> mIrs{};
 386     std::atomic<size_t> mCurrent{};
 387     std::atomic<size_t> mDone{};
 388
 389     void Worker()
 390     {
 391         auto htemp = std::vector<complex_d>(mFftSize);
 392
 393         while(true)
 394         {
 395             /* Load the current index to process. */
 396             size_t idx{mCurrent.load()};
 397             do {
 398                 /* If the index is at the end, we're done. */
 399                 if(idx >= mIrs.size())
 400                     return;
 401                 /* Otherwise, increment the current index atomically so other
 402                  * threads know to go to the next one. If this call fails, the
 403                  * current index was just changed by another thread and the new
 404                  * value is loaded into idx, which we'll recheck.
 405                  */
 406             } while(!mCurrent.compare_exchange_weak(idx, idx+1, std::memory_order_relaxed));
 407
 408             CalcHrirMagnitude(mIrPoints, htemp, mIrs[idx]);
 409
 410             /* Increment the number of IRs done. */
 411             mDone.fetch_add(1);
 412         }
 413     }
 414 };
 415
 416 } // namespace
 417
 418 bool LoadSofaFile(const std::string_view filename, const uint numThreads, const uint fftSize,
 419     const uint truncSize, const uint outRate, const ChannelModeT chanMode, HrirDataT *hData)
 420 {
 421     int err;
 422     MySofaHrtfPtr sofaHrtf{mysofa_load(std::string{filename}.c_str(), &err)};
 423     if(!sofaHrtf)
 424     {
 425         fprintf(stdout, "Error: Could not load %.*s: %s\n", al::sizei(filename), filename.data(),
 426             SofaErrorStr(err));
 427         return false;
 428     }
 429
 430     /* NOTE: Some valid SOFA files are failing this check. */
 431     err = mysofa_check(sofaHrtf.get());
 432     if(err != MYSOFA_OK)
 433         fprintf(stderr, "Warning: Supposedly malformed source file '%.*s' (%s).\n",
 434             al::sizei(filename), filename.data(), SofaErrorStr(err));
 435
 436     mysofa_tocartesian(sofaHrtf.get());
 437
 438     /* Make sure emitter and receiver counts are sane. */
 439     if(sofaHrtf->E != 1)
 440     {
 441         fprintf(stderr, "%u emitters not supported\n", sofaHrtf->E);
 442         return false;
 443     }
 444     if(sofaHrtf->R > 2 || sofaHrtf->R < 1)
 445     {
 446         fprintf(stderr, "%u receivers not supported\n", sofaHrtf->R);
 447         return false;
 448     }
 449     /* Assume R=2 is a stereo measurement, and R=1 is mono left-ear-only. */
 450     if(sofaHrtf->R == 2 && chanMode == CM_AllowStereo)
 451         hData->mChannelType = CT_STEREO;
 452     else
 453         hData->mChannelType = CT_MONO;
 454
 455     /* Check and set the FFT and IR size. */
 456     if(sofaHrtf->N > fftSize)
 457     {
 458         fprintf(stderr, "Sample points exceeds the FFT size.\n");
 459         return false;
 460     }
 461     if(sofaHrtf->N < truncSize)
 462     {
 463         fprintf(stderr, "Sample points is below the truncation size.\n");
 464         return false;
 465     }
 466     hData->mIrPoints = sofaHrtf->N;
 467     hData->mFftSize = fftSize;
 468     hData->mIrSize = std::max(1u + (fftSize/2u), sofaHrtf->N);
 469
 470     /* Assume a default head radius of 9cm. */
 471     hData->mRadius = 0.09;
 472
 473     hData->mIrRate = static_cast<uint>(std::lround(GetSampleRate(sofaHrtf.get())));
 474     if(!hData->mIrRate)
 475         return false;
 476
 477     const auto delayType = PrepareDelay(sofaHrtf.get());
 478     if(!delayType)
 479         return false;
 480
 481     if(!CheckIrData(sofaHrtf.get()))
 482         return false;
 483     if(!PrepareLayout(al::span{sofaHrtf->SourcePosition.values, sofaHrtf->M*3_uz}, hData))
 484         return false;
 485     if(!LoadResponses(sofaHrtf.get(), hData, *delayType, outRate))
 486         return false;
 487     sofaHrtf = nullptr;
 488
 489     for(uint fi{0u};fi < hData->mFds.size();fi++)
 490     {
 491         uint ei{0u};
 492         for(;ei < hData->mFds[fi].mEvs.size();ei++)
 493         {
 494             uint ai{0u};
 495             for(;ai < hData->mFds[fi].mEvs[ei].mAzs.size();ai++)
 496             {
 497                 HrirAzT &azd = hData->mFds[fi].mEvs[ei].mAzs[ai];
 498                 if(!azd.mIrs[0].empty()) break;
 499             }
 500             if(ai < hData->mFds[fi].mEvs[ei].mAzs.size())
 501                 break;
 502         }
 503         if(ei >= hData->mFds[fi].mEvs.size())
 504         {
 505             fprintf(stderr, "Missing source references [ %d, *, * ].\n", fi);
 506             return false;
 507         }
 508         hData->mFds[fi].mEvStart = ei;
 509         for(;ei < hData->mFds[fi].mEvs.size();ei++)
 510         {
 511             for(uint ai{0u};ai < hData->mFds[fi].mEvs[ei].mAzs.size();ai++)
 512             {
 513                 HrirAzT &azd = hData->mFds[fi].mEvs[ei].mAzs[ai];
 514                 if(azd.mIrs[0].empty())
 515                 {
 516                     fprintf(stderr, "Missing source reference [ %d, %d, %d ].\n", fi, ei, ai);
 517                     return false;
 518                 }
 519             }
 520         }
 521     }
 522
 523
 524     size_t hrir_total{0};
 525     const uint channels{(hData->mChannelType == CT_STEREO) ? 2u : 1u};
 526     const auto hrirs = al::span{hData->mHrirsBase};
 527     for(uint fi{0u};fi < hData->mFds.size();fi++)
 528     {
 529         for(uint ei{0u};ei < hData->mFds[fi].mEvStart;ei++)
 530         {
 531             for(uint ai{0u};ai < hData->mFds[fi].mEvs[ei].mAzs.size();ai++)
 532             {
 533                 HrirAzT &azd = hData->mFds[fi].mEvs[ei].mAzs[ai];
 534                 for(size_t ti{0u};ti < channels;ti++)
 535                     azd.mIrs[ti] = hrirs.subspan((hData->mIrCount*ti + azd.mIndex)*hData->mIrSize,
 536                         hData->mIrSize);
 537             }
 538         }
 539
 540         for(uint ei{hData->mFds[fi].mEvStart};ei < hData->mFds[fi].mEvs.size();ei++)
 541             hrir_total += hData->mFds[fi].mEvs[ei].mAzs.size() * channels;
 542     }
 543
 544     std::atomic<size_t> hrir_done{0};
 545     auto onset_proc = [hData,channels,&hrir_done]() -> bool
 546     {
 547         /* Temporary buffer used to calculate the IR's onset. */
 548         auto upsampled = std::vector<double>(size_t{OnsetRateMultiple} * hData->mIrPoints);
 549         /* This resampler is used to help detect the response onset. */
 550         PPhaseResampler rs;
 551         rs.init(hData->mIrRate, OnsetRateMultiple*hData->mIrRate);
 552
 553         for(auto &field : hData->mFds)
 554         {
 555             for(auto &elev : field.mEvs.subspan(field.mEvStart))
 556             {
 557                 for(auto &azd : elev.mAzs)
 558                 {
 559                     for(uint ti{0};ti < channels;ti++)
 560                     {
 561                         hrir_done.fetch_add(1u, std::memory_order_acq_rel);
 562                         azd.mDelays[ti] += CalcHrirOnset(rs, hData->mIrRate, upsampled,
 563                             azd.mIrs[ti].first(hData->mIrPoints));
 564                     }
 565                 }
 566             }
 567         }
 568         return true;
 569     };
 570
 571     std::future_status load_status{};
 572     auto load_future = std::async(std::launch::async, onset_proc);
 573     do {
 574         load_status = load_future.wait_for(std::chrono::milliseconds{50});
 575         printf("\rCalculating HRIR onsets... %zu of %zu", hrir_done.load(), hrir_total);
 576         fflush(stdout);
 577     } while(load_status != std::future_status::ready);
 578     fputc('\n', stdout);
 579     if(!load_future.get())
 580         return false;
 581
 582     MagCalculator calculator{hData->mFftSize, hData->mIrPoints};
 583     for(auto &field : hData->mFds)
 584     {
 585         for(auto &elev : field.mEvs.subspan(field.mEvStart))
 586         {
 587             for(auto &azd : elev.mAzs)
 588             {
 589                 for(uint ti{0};ti < channels;ti++)
 590                     calculator.mIrs.push_back(azd.mIrs[ti]);
 591             }
 592         }
 593     }
 594
 595     std::vector<std::thread> thrds;
 596     thrds.reserve(numThreads);
 597     for(size_t i{0};i < numThreads;++i)
 598         thrds.emplace_back(std::mem_fn(&MagCalculator::Worker), &calculator);
 599     size_t count;
 600     do {
 601         std::this_thread::sleep_for(std::chrono::milliseconds{50});
 602         count = calculator.mDone.load();
 603
 604         printf("\rCalculating HRIR magnitudes... %zu of %zu", count, calculator.mIrs.size());
 605         fflush(stdout);
 606     } while(count != calculator.mIrs.size());
 607     fputc('\n', stdout);
 608
 609     for(auto &thrd : thrds)
 610     {
 611         if(thrd.joinable())
 612             thrd.join();
 613     }
 614     return true;
 615 }