/* * HRTF utility for producing and demonstrating the process of creating an * OpenAL Soft compatible HRIR data set. * * Copyright (C) 2018-2019 Christopher Fitzgerald * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * * Or visit: http://www.gnu.org/licenses/old-licenses/gpl-2.0.html */ #include <memory> #include <numeric> #include <algorithm> #include "mysofa.h" #include "loadsofa.h" static const char *SofaErrorStr(int err) { switch(err) { case MYSOFA_OK: return "OK"; case MYSOFA_INVALID_FORMAT: return "Invalid format"; case MYSOFA_UNSUPPORTED_FORMAT: return "Unsupported format"; case MYSOFA_INTERNAL_ERROR: return "Internal error"; case MYSOFA_NO_MEMORY: return "Out of memory"; case MYSOFA_READ_ERROR: return "Read error"; } return "Unknown"; } /* Produces a sorted array of unique elements from a particular axis of the * triplets array. The filters are used to focus on particular coordinates * of other axes as necessary. The epsilons are used to constrain the * equality of unique elements. */ static uint GetUniquelySortedElems(const uint m, const float *triplets, const int axis, const double *const (&filters)[3], const double (&epsilons)[3], float *elems) { uint count{0u}; for(uint i{0u};i < 3*m;i += 3) { const float elem{triplets[i + axis]}; uint j; for(j = 0;j < 3;j++) { if(filters[j] && std::fabs(triplets[i + j] - *filters[j]) > epsilons[j]) break; } if(j < 3) continue; for(j = 0;j < count;j++) { const float delta{elem - elems[j]}; if(delta > epsilons[axis]) continue; if(delta >= -epsilons[axis]) break; for(uint k{count};k > j;k--) elems[k] = elems[k - 1]; elems[j] = elem; count++; break; } if(j >= count) elems[count++] = elem; } return count; } /* Given a list of elements, this will produce the smallest step size that * can uniformly cover a fair portion of the list. Ideally this will be over * half, but in degenerate cases this can fall to a minimum of 5 (the lower * limit on elevations necessary to build a layout). */ static float GetUniformStepSize(const double epsilon, const uint m, const float *elems) { auto steps = std::vector<float>(m, 0.0f); auto counts = std::vector<uint>(m, 0u); float step{0.0f}; uint count{0u}; for(uint stride{1u};stride < m/2;stride++) { for(uint i{0u};i < m-stride;i++) { const float step{elems[i + stride] - elems[i]}; uint j; for(j = 0;j < count;j++) { if(std::fabs(step - steps[j]) < epsilon) { counts[j]++; break; } } if(j >= count) { steps[j] = step; counts[j] = 1; count++; } } for(uint i{1u};i < count;i++) { if(counts[i] > counts[0]) { steps[0] = steps[i]; counts[0] = counts[i]; } } count = 1; if(counts[0] > m/2) { step = steps[0]; return step; } } if(counts[0] > 5) step = steps[0]; return step; } /* Attempts to produce a compatible layout. Most data sets tend to be * uniform and have the same major axis as used by OpenAL Soft's HRTF model. * This will remove outliers and produce a maximally dense layout when * possible. Those sets that contain purely random measurements or use * different major axes will fail. */ static bool PrepareLayout(const uint m, const float *xyzs, HrirDataT *hData) { std::vector<float> aers(3*m, 0.0f); std::vector<float> elems(m, 0.0f); for(uint i{0u};i < 3*m;i += 3) { aers[i] = xyzs[i]; aers[i + 1] = xyzs[i + 1]; aers[i + 2] = xyzs[i + 2]; mysofa_c2s(&aers[i]); } const uint fdCount{GetUniquelySortedElems(m, aers.data(), 2, { nullptr, nullptr, nullptr }, { 0.1, 0.1, 0.001 }, elems.data())}; if(fdCount > MAX_FD_COUNT) { fprintf(stdout, "Incompatible layout (inumerable radii).\n"); return false; } double distances[MAX_FD_COUNT]{}; uint evCounts[MAX_FD_COUNT]{}; auto azCounts = std::vector<uint>(MAX_FD_COUNT * MAX_EV_COUNT); for(uint fi{0u};fi < fdCount;fi++) { distances[fi] = elems[fi]; if(fi > 0 && distances[fi] <= distances[fi-1]) { fprintf(stderr, "Distances must increase.\n"); return 0; } } if(distances[0] < hData->mRadius) { fprintf(stderr, "Distance cannot start below head radius.\n"); return 0; } for(uint fi{0u};fi < fdCount;fi++) { const double dist{distances[fi]}; uint evCount{GetUniquelySortedElems(m, aers.data(), 1, { nullptr, nullptr, &dist }, { 0.1, 0.1, 0.001 }, elems.data())}; if(evCount > MAX_EV_COUNT) { fprintf(stderr, "Incompatible layout (innumerable elevations).\n"); return false; } float step{GetUniformStepSize(0.1, evCount, elems.data())}; if(step <= 0.0f) { fprintf(stderr, "Incompatible layout (non-uniform elevations).\n"); return false; } uint evStart{0u}; for(uint ei{0u};ei < evCount;ei++) { float ev{90.0f + elems[ei]}; float eif{std::round(ev / step)}; if(std::fabs(eif - (uint)eif) < (0.1f / step)) { evStart = static_cast<uint>(eif); break; } } evCount = static_cast<uint>(std::round(180.0f / step)) + 1; if(evCount < 5) { fprintf(stderr, "Incompatible layout (too few uniform elevations).\n"); return false; } evCounts[fi] = evCount; for(uint ei{evStart};ei < evCount;ei++) { const double ev{-90.0 + ei*180.0/(evCount - 1)}; const uint azCount{GetUniquelySortedElems(m, aers.data(), 0, { nullptr, &ev, &dist }, { 0.1, 0.1, 0.001 }, elems.data())}; if(azCount > MAX_AZ_COUNT) { fprintf(stderr, "Incompatible layout (innumerable azimuths).\n"); return false; } if(ei > 0 && ei < (evCount - 1)) { step = GetUniformStepSize(0.1, azCount, elems.data()); if(step <= 0.0f) { fprintf(stderr, "Incompatible layout (non-uniform azimuths).\n"); return false; } azCounts[fi*MAX_EV_COUNT + ei] = static_cast<uint>(std::round(360.0f / step)); } else if(azCount != 1) { fprintf(stderr, "Incompatible layout (non-singular poles).\n"); return false; } else { azCounts[fi*MAX_EV_COUNT + ei] = 1; } } for(uint ei{0u};ei < evStart;ei++) azCounts[fi*MAX_EV_COUNT + ei] = azCounts[fi*MAX_EV_COUNT + evCount - ei - 1]; } return PrepareHrirData(fdCount, distances, evCounts, azCounts.data(), hData) != 0; } bool PrepareSampleRate(MYSOFA_HRTF *sofaHrtf, HrirDataT *hData) { const char *srate_dim{nullptr}; const char *srate_units{nullptr}; MYSOFA_ARRAY *srate_array{&sofaHrtf->DataSamplingRate}; MYSOFA_ATTRIBUTE *srate_attrs{srate_array->attributes}; while(srate_attrs) { if(std::string{"DIMENSION_LIST"} == srate_attrs->name) { if(srate_dim) { fprintf(stderr, "Duplicate SampleRate.DIMENSION_LIST\n"); return false; } srate_dim = srate_attrs->value; } else if(std::string{"Units"} == srate_attrs->name) { if(srate_units) { fprintf(stderr, "Duplicate SampleRate.Units\n"); return false; } srate_units = srate_attrs->value; } else fprintf(stderr, "Unexpected sample rate attribute: %s = %s\n", srate_attrs->name, srate_attrs->value); srate_attrs = srate_attrs->next; } if(!srate_dim) { fprintf(stderr, "Missing sample rate dimensions\n"); return false; } if(srate_dim != std::string{"I"}) { fprintf(stderr, "Unsupported sample rate dimensions: %s\n", srate_dim); return false; } if(!srate_units) { fprintf(stderr, "Missing sample rate unit type\n"); return false; } if(srate_units != std::string{"hertz"}) { fprintf(stderr, "Unsupported sample rate unit type: %s\n", srate_units); return false; } /* I dimensions guarantees 1 element, so just extract it. */ hData->mIrRate = static_cast<uint>(srate_array->values[0] + 0.5f); if(hData->mIrRate < MIN_RATE || hData->mIrRate > MAX_RATE) { fprintf(stderr, "Sample rate out of range: %u (expected %u to %u)", hData->mIrRate, MIN_RATE, MAX_RATE); return false; } return true; } bool PrepareDelay(MYSOFA_HRTF *sofaHrtf, HrirDataT *hData) { const char *delay_dim{nullptr}; MYSOFA_ARRAY *delay_array{&sofaHrtf->DataDelay}; MYSOFA_ATTRIBUTE *delay_attrs{delay_array->attributes}; while(delay_attrs) { if(std::string{"DIMENSION_LIST"} == delay_attrs->name) { if(delay_dim) { fprintf(stderr, "Duplicate Delay.DIMENSION_LIST\n"); return false; } delay_dim = delay_attrs->value; } else fprintf(stderr, "Unexpected delay attribute: %s = %s\n", delay_attrs->name, delay_attrs->value); delay_attrs = delay_attrs->next; } if(!delay_dim) { fprintf(stderr, "Missing delay dimensions\n"); /*return false;*/ } else if(delay_dim != std::string{"I,R"}) { fprintf(stderr, "Unsupported delay dimensions: %s\n", delay_dim); return false; } else if(hData->mChannelType == CT_STEREO) { /* I,R is 1xChannelCount. Makemhr currently removes any delay constant, * so we can ignore this as long as it's equal. */ if(delay_array->values[0] != delay_array->values[1]) { fprintf(stderr, "Mismatched delays not supported: %f, %f\n", delay_array->values[0], delay_array->values[1]); return false; } } return true; } bool CheckIrData(MYSOFA_HRTF *sofaHrtf) { const char *ir_dim{nullptr}; MYSOFA_ARRAY *ir_array{&sofaHrtf->DataIR}; MYSOFA_ATTRIBUTE *ir_attrs{ir_array->attributes}; while(ir_attrs) { if(std::string{"DIMENSION_LIST"} == ir_attrs->name) { if(ir_dim) { fprintf(stderr, "Duplicate IR.DIMENSION_LIST\n"); return false; } ir_dim = ir_attrs->value; } else fprintf(stderr, "Unexpected IR attribute: %s = %s\n", ir_attrs->name, ir_attrs->value); ir_attrs = ir_attrs->next; } if(!ir_dim) { fprintf(stderr, "Missing IR dimensions\n"); return false; } if(ir_dim != std::string{"M,R,N"}) { fprintf(stderr, "Unsupported IR dimensions: %s\n", ir_dim); return false; } return true; } /* Calculate the onset time of a HRIR. */ static double CalcHrirOnset(const uint rate, const uint n, std::vector<double> &upsampled, const double *hrir) { { ResamplerT rs; ResamplerSetup(&rs, rate, 10 * rate); ResamplerRun(&rs, n, hrir, 10 * n, upsampled.data()); } double mag{std::accumulate(upsampled.cbegin(), upsampled.cend(), double{0.0}, [](const double mag, const double sample) -> double { return std::max(mag, std::abs(sample)); })}; mag *= 0.15; auto iter = std::find_if(upsampled.cbegin(), upsampled.cend(), [mag](const double sample) -> bool { return (std::abs(sample) >= mag); }); return static_cast<double>(std::distance(upsampled.cbegin(), iter)) / (10.0*rate); } /* Calculate the magnitude response of a HRIR. */ static void CalcHrirMagnitude(const uint points, const uint n, std::vector<complex_d> &h, const double *hrir, double *mag) { auto iter = std::copy_n(hrir, points, h.begin()); std::fill(iter, h.end(), complex_d{0.0, 0.0}); FftForward(n, h.data()); MagnitudeResponse(n, h.data(), mag); } static bool LoadResponses(MYSOFA_HRTF *sofaHrtf, HrirDataT *hData) { const uint channels{(hData->mChannelType == CT_STEREO) ? 2u : 1u}; hData->mHrirsBase.resize(channels * hData->mIrCount * hData->mIrSize); double *hrirs = hData->mHrirsBase.data(); /* Temporary buffers used to calculate the IR's onset and frequency * magnitudes. */ auto upsampled = std::vector<double>(10 * hData->mIrPoints); auto htemp = std::vector<complex_d>(hData->mFftSize); auto hrir = std::vector<double>(hData->mFftSize); for(uint si{0u};si < sofaHrtf->M;si++) { printf("\rLoading HRIRs... %d of %d", si+1, sofaHrtf->M); fflush(stdout); float aer[3]{ sofaHrtf->SourcePosition.values[3*si], sofaHrtf->SourcePosition.values[3*si + 1], sofaHrtf->SourcePosition.values[3*si + 2] }; mysofa_c2s(aer); if(std::abs(aer[1]) >= 89.999f) aer[0] = 0.0f; else aer[0] = std::fmod(360.0f - aer[0], 360.0f); auto field = std::find_if(hData->mFds.cbegin(), hData->mFds.cend(), [&aer](const HrirFdT &fld) -> bool { double delta = aer[2] - fld.mDistance; return (std::abs(delta) < 0.001); }); if(field == hData->mFds.cend()) continue; double ef{(90.0+aer[1]) * (field->mEvCount-1) / 180.0}; auto ei = static_cast<int>(std::round(ef)); ef = (ef-ei) * 180.0f / (field->mEvCount-1); if(std::abs(ef) >= 0.1) continue; double af{aer[0] * field->mEvs[ei].mAzCount / 360.0f}; auto ai = static_cast<int>(std::round(af)); af = (af-ai) * 360.0f / field->mEvs[ei].mAzCount; ai %= field->mEvs[ei].mAzCount; if(std::abs(af) >= 0.1) continue; HrirAzT *azd = &field->mEvs[ei].mAzs[ai]; if(azd->mIrs[0] != nullptr) { fprintf(stderr, "Multiple measurements near [ a=%f, e=%f, r=%f ].\n", aer[0], aer[1], aer[2]); return false; } for(uint ti{0u};ti < channels;++ti) { std::copy_n(&sofaHrtf->DataIR.values[(si*sofaHrtf->R + ti)*sofaHrtf->N], hData->mIrPoints, hrir.begin()); azd->mIrs[ti] = &hrirs[hData->mIrSize * (hData->mIrCount*ti + azd->mIndex)]; azd->mDelays[ti] = CalcHrirOnset(hData->mIrRate, hData->mIrPoints, upsampled, hrir.data()); CalcHrirMagnitude(hData->mIrPoints, hData->mFftSize, htemp, hrir.data(), azd->mIrs[ti]); } // TODO: Since some SOFA files contain minimum phase HRIRs, // it would be beneficial to check for per-measurement delays // (when available) to reconstruct the HRTDs. } printf("\n"); return true; } struct MySofaHrtfDeleter { void operator()(MYSOFA_HRTF *ptr) { mysofa_free(ptr); } }; using MySofaHrtfPtr = std::unique_ptr<MYSOFA_HRTF,MySofaHrtfDeleter>; bool LoadSofaFile(const char *filename, const uint fftSize, const uint truncSize, const ChannelModeT chanMode, HrirDataT *hData) { int err; MySofaHrtfPtr sofaHrtf{mysofa_load(filename, &err)}; if(!sofaHrtf) { fprintf(stdout, "Error: Could not load %s: %s\n", filename, SofaErrorStr(err)); return false; } err = mysofa_check(sofaHrtf.get()); if(err != MYSOFA_OK) /* NOTE: Some valid SOFA files are failing this check. { fprintf(stdout, "Error: Malformed source file '%s' (%s).\n", filename, SofaErrorStr(err)); return false; } */ fprintf(stderr, "Warning: Supposedly malformed source file '%s' (%s).\n", filename, SofaErrorStr(err)); mysofa_tocartesian(sofaHrtf.get()); /* Make sure emitter and receiver counts are sane. */ if(sofaHrtf->E != 1) { fprintf(stderr, "%u emitters not supported\n", sofaHrtf->E); return false; } if(sofaHrtf->R > 2 || sofaHrtf->R < 1) { fprintf(stderr, "%u receivers not supported\n", sofaHrtf->R); return false; } /* Assume R=2 is a stereo measurement, and R=1 is mono left-ear-only. */ if(sofaHrtf->R == 2 && chanMode == CM_AllowStereo) hData->mChannelType = CT_STEREO; else hData->mChannelType = CT_MONO; /* Check and set the FFT and IR size. */ if(sofaHrtf->N > fftSize) { fprintf(stderr, "Sample points exceeds the FFT size.\n"); return false; } if(sofaHrtf->N < truncSize) { fprintf(stderr, "Sample points is below the truncation size.\n"); return false; } hData->mIrPoints = sofaHrtf->N; hData->mFftSize = fftSize; hData->mIrSize = std::max(1u + (fftSize/2u), sofaHrtf->N); /* Assume a default head radius of 9cm. */ hData->mRadius = 0.09; if(!PrepareSampleRate(sofaHrtf.get(), hData) || !PrepareDelay(sofaHrtf.get(), hData) || !CheckIrData(sofaHrtf.get())) return false; if(!PrepareLayout(sofaHrtf->M, sofaHrtf->SourcePosition.values, hData)) return false; if(!LoadResponses(sofaHrtf.get(), hData)) return false; sofaHrtf = nullptr; for(uint fi{0u};fi < hData->mFdCount;fi++) { uint ei{0u}; for(;ei < hData->mFds[fi].mEvCount;ei++) { uint ai{0u}; for(;ai < hData->mFds[fi].mEvs[ei].mAzCount;ai++) { HrirAzT &azd = hData->mFds[fi].mEvs[ei].mAzs[ai]; if(azd.mIrs[0] != nullptr) break; } if(ai < hData->mFds[fi].mEvs[ei].mAzCount) break; } if(ei >= hData->mFds[fi].mEvCount) { fprintf(stderr, "Missing source references [ %d, *, * ].\n", fi); return false; } hData->mFds[fi].mEvStart = ei; for(;ei < hData->mFds[fi].mEvCount;ei++) { for(uint ai{0u};ai < hData->mFds[fi].mEvs[ei].mAzCount;ai++) { HrirAzT &azd = hData->mFds[fi].mEvs[ei].mAzs[ai]; if(azd.mIrs[0] == nullptr) { fprintf(stderr, "Missing source reference [ %d, %d, %d ].\n", fi, ei, ai); return false; } } } } const uint channels{(hData->mChannelType == CT_STEREO) ? 2u : 1u}; double *hrirs = hData->mHrirsBase.data(); for(uint fi{0u};fi < hData->mFdCount;fi++) { for(uint ei{0u};ei < hData->mFds[fi].mEvCount;ei++) { for(uint ai{0u};ai < hData->mFds[fi].mEvs[ei].mAzCount;ai++) { HrirAzT &azd = hData->mFds[fi].mEvs[ei].mAzs[ai]; for(uint ti{0u};ti < channels;ti++) azd.mIrs[ti] = &hrirs[hData->mIrSize * (hData->mIrCount*ti + azd.mIndex)]; } } } return true; }