utils/sofa-info.cpp

   1 /*
   2  * SOFA info utility for inspecting SOFA file metrics and determining HRTF
   3  * utility compatible layouts.
   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 <stdio.h>
  25
  26 #include <array>
  27 #include <cmath>
  28 #include <memory>
  29 #include <vector>
  30
  31 #include <mysofa.h>
  32
  33 #include "win_main_utf8.h"
  34
  35
  36 using uint = unsigned int;
  37 using double3 = std::array<double,3>;
  38
  39 struct MySofaDeleter {
  40     void operator()(MYSOFA_HRTF *sofa) { mysofa_free(sofa); }
  41 };
  42 using MySofaHrtfPtr = std::unique_ptr<MYSOFA_HRTF,MySofaDeleter>;
  43
  44 // Per-field measurement info.
  45 struct HrirFdT {
  46     double mDistance{0.0};
  47     uint mEvCount{0u};
  48     uint mEvStart{0u};
  49     std::vector<uint> mAzCounts;
  50 };
  51
  52 static const char *SofaErrorStr(int err)
  53 {
  54     switch(err)
  55     {
  56     case MYSOFA_OK: return "OK";
  57     case MYSOFA_INVALID_FORMAT: return "Invalid format";
  58     case MYSOFA_UNSUPPORTED_FORMAT: return "Unsupported format";
  59     case MYSOFA_INTERNAL_ERROR: return "Internal error";
  60     case MYSOFA_NO_MEMORY: return "Out of memory";
  61     case MYSOFA_READ_ERROR: return "Read error";
  62     }
  63     return "Unknown";
  64 }
  65
  66 static void PrintSofaAttributes(const char *prefix, struct MYSOFA_ATTRIBUTE *attribute)
  67 {
  68     while(attribute)
  69     {
  70         fprintf(stdout, "%s.%s: %s\n", prefix, attribute->name, attribute->value);
  71         attribute = attribute->next;
  72     }
  73 }
  74
  75 static void PrintSofaArray(const char *prefix, struct MYSOFA_ARRAY *array)
  76 {
  77     PrintSofaAttributes(prefix, array->attributes);
  78
  79     for(uint i{0u};i < array->elements;i++)
  80         fprintf(stdout, "%s[%u]: %.6f\n", prefix, i, array->values[i]);
  81 }
  82
  83 /* Produces a sorted array of unique elements from a particular axis of the
  84  * triplets array.  The filters are used to focus on particular coordinates
  85  * of other axes as necessary.  The epsilons are used to constrain the
  86  * equality of unique elements.
  87  */
  88 static uint GetUniquelySortedElems(const uint m, const double3 *aers, const uint axis,
  89     const double *const (&filters)[3], const double (&epsilons)[3], double *elems)
  90 {
  91     uint count{0u};
  92     for(uint i{0u};i < m;++i)
  93     {
  94         const double elem{aers[i][axis]};
  95
  96         uint j;
  97         for(j = 0;j < 3;j++)
  98         {
  99             if(filters[j] && std::fabs(aers[i][j] - *filters[j]) > epsilons[j])
 100                 break;
 101         }
 102         if(j < 3)
 103             continue;
 104
 105         for(j = 0;j < count;j++)
 106         {
 107             const double delta{elem - elems[j]};
 108
 109             if(delta > epsilons[axis])
 110                 continue;
 111
 112             if(delta >= -epsilons[axis])
 113                 break;
 114
 115             for(uint k{count};k > j;k--)
 116                 elems[k] = elems[k - 1];
 117
 118             elems[j] = elem;
 119             count++;
 120             break;
 121         }
 122
 123         if(j >= count)
 124             elems[count++] = elem;
 125     }
 126
 127     return count;
 128 }
 129
 130 /* Given a list of elements, this will produce the smallest step size that
 131  * can uniformly cover a fair portion of the list.  Ideally this will be over
 132  * half, but in degenerate cases this can fall to a minimum of 5 (the lower
 133  * limit on elevations necessary to build a layout).
 134  */
 135 static double GetUniformStepSize(const double epsilon, const uint m, const double *elems)
 136 {
 137     auto steps = std::vector<double>(m, 0.0);
 138     auto counts = std::vector<uint>(m, 0u);
 139     uint count{0u};
 140
 141     for(uint stride{1u};stride < m/2;stride++)
 142     {
 143         for(uint i{0u};i < m-stride;i++)
 144         {
 145             const double step{elems[i + stride] - elems[i]};
 146
 147             uint j;
 148             for(j = 0;j < count;j++)
 149             {
 150                 if(std::fabs(step - steps[j]) < epsilon)
 151                 {
 152                     counts[j]++;
 153                     break;
 154                 }
 155             }
 156
 157             if(j >= count)
 158             {
 159                 steps[j] = step;
 160                 counts[j] = 1;
 161                 count++;
 162             }
 163         }
 164
 165         for(uint i{1u};i < count;i++)
 166         {
 167             if(counts[i] > counts[0])
 168             {
 169                 steps[0] = steps[i];
 170                 counts[0] = counts[i];
 171             }
 172         }
 173
 174         count = 1;
 175
 176         if(counts[0] > m/2)
 177             return steps[0];
 178     }
 179
 180     if(counts[0] > 5)
 181         return steps[0];
 182     return 0.0;
 183 }
 184
 185 /* Attempts to produce a compatible layout.  Most data sets tend to be
 186  * uniform and have the same major axis as used by OpenAL Soft's HRTF model.
 187  * This will remove outliers and produce a maximally dense layout when
 188  * possible.  Those sets that contain purely random measurements or use
 189  * different major axes will fail.
 190  */
 191 static void PrintCompatibleLayout(const uint m, const float *xyzs)
 192 {
 193     auto aers = std::vector<double3>(m, double3{});
 194     auto elems = std::vector<double>(m, {});
 195
 196     fprintf(stdout, "\n");
 197
 198     for(uint i{0u};i < m;++i)
 199     {
 200         float aer[3]{xyzs[i*3], xyzs[i*3 + 1], xyzs[i*3 + 2]};
 201         mysofa_c2s(&aer[0]);
 202         aers[i][0] = aer[0];
 203         aers[i][1] = aer[1];
 204         aers[i][2] = aer[2];
 205     }
 206
 207     uint fdCount{GetUniquelySortedElems(m, aers.data(), 2, { nullptr, nullptr, nullptr },
 208         { 0.1, 0.1, 0.001 }, elems.data())};
 209     if(fdCount > (m / 3))
 210     {
 211         fprintf(stdout, "Incompatible layout (inumerable radii).\n");
 212         return;
 213     }
 214
 215     std::vector<HrirFdT> fds(fdCount);
 216     for(uint fi{0u};fi < fdCount;fi++)
 217         fds[fi].mDistance = elems[fi];
 218
 219     for(uint fi{0u};fi < fdCount;fi++)
 220     {
 221         const double dist{fds[fi].mDistance};
 222         uint evCount{GetUniquelySortedElems(m, aers.data(), 1, { nullptr, nullptr, &dist },
 223             { 0.1, 0.1, 0.001 }, elems.data())};
 224
 225         if(evCount > (m / 3))
 226         {
 227             fprintf(stdout, "Incompatible layout (innumerable elevations).\n");
 228             return;
 229         }
 230
 231         double step{GetUniformStepSize(0.1, evCount, elems.data())};
 232         if(step <= 0.0)
 233         {
 234             fprintf(stdout, "Incompatible layout (non-uniform elevations).\n");
 235             return;
 236         }
 237
 238         uint evStart{0u};
 239         for(uint ei{0u};ei < evCount;ei++)
 240         {
 241             double ev{90.0 + elems[ei]};
 242             double eif{std::round(ev / step)};
 243             const uint ev_start{static_cast<uint>(eif)};
 244
 245             if(std::fabs(eif - static_cast<double>(ev_start)) < (0.1/step))
 246             {
 247                 evStart = ev_start;
 248                 break;
 249             }
 250         }
 251
 252         evCount = static_cast<uint>(std::round(180.0 / step)) + 1;
 253         if(evCount < 5)
 254         {
 255             fprintf(stdout, "Incompatible layout (too few uniform elevations).\n");
 256             return;
 257         }
 258
 259         fds[fi].mEvCount = evCount;
 260         fds[fi].mEvStart = evStart;
 261         fds[fi].mAzCounts.resize(evCount);
 262         auto &azCounts = fds[fi].mAzCounts;
 263
 264         for(uint ei{evStart};ei < evCount;ei++)
 265         {
 266             double ev{-90.0 + static_cast<double>(ei)*180.0/static_cast<double>(evCount - 1)};
 267             uint azCount{GetUniquelySortedElems(m, aers.data(), 0, { nullptr, &ev, &dist },
 268                 { 0.1, 0.1, 0.001 }, elems.data())};
 269
 270             if(azCount > (m / 3))
 271             {
 272                 fprintf(stdout, "Incompatible layout (innumerable azimuths).\n");
 273                 return;
 274             }
 275
 276             if(ei > 0 && ei < (evCount - 1))
 277             {
 278                 step = GetUniformStepSize(0.1, azCount, elems.data());
 279                 if(step <= 0.0)
 280                 {
 281                     fprintf(stdout, "Incompatible layout (non-uniform azimuths).\n");
 282                     return;
 283                 }
 284
 285                 azCounts[ei] = static_cast<uint>(std::round(360.0f / step));
 286             }
 287             else if(azCount != 1)
 288             {
 289                 fprintf(stdout, "Incompatible layout (non-singular poles).\n");
 290                 return;
 291             }
 292             else
 293             {
 294                 azCounts[ei] = 1;
 295             }
 296         }
 297
 298         for(uint ei{0u};ei < evStart;ei++)
 299             azCounts[ei] = azCounts[evCount - ei - 1];
 300     }
 301
 302     fprintf(stdout, "Compatible Layout:\n\ndistance = %.3f", fds[0].mDistance);
 303
 304     for(uint fi{1u};fi < fdCount;fi++)
 305         fprintf(stdout, ", %.3f", fds[fi].mDistance);
 306
 307     fprintf(stdout, "\nazimuths = ");
 308     for(uint fi{0u};fi < fdCount;fi++)
 309     {
 310         for(uint ei{0u};ei < fds[fi].mEvCount;ei++)
 311             fprintf(stdout, "%d%s", fds[fi].mAzCounts[ei],
 312                 (ei < (fds[fi].mEvCount - 1)) ? ", " :
 313                 (fi < (fdCount - 1)) ? ";\n           " : "\n");
 314     }
 315 }
 316
 317 // Load and inspect the given SOFA file.
 318 static void SofaInfo(const char *filename)
 319 {
 320     int err;
 321     MySofaHrtfPtr sofa{mysofa_load(filename, &err)};
 322     if(!sofa)
 323     {
 324         fprintf(stdout, "Error: Could not load source file '%s'.\n", filename);
 325         return;
 326     }
 327
 328     /* NOTE: Some valid SOFA files are failing this check. */
 329     err = mysofa_check(sofa.get());
 330     if(err != MYSOFA_OK)
 331         fprintf(stdout, "Warning: Supposedly malformed source file '%s' (%s).\n", filename,
 332             SofaErrorStr(err));
 333
 334     mysofa_tocartesian(sofa.get());
 335
 336     PrintSofaAttributes("Info", sofa->attributes);
 337
 338     fprintf(stdout, "Measurements: %u\n", sofa->M);
 339     fprintf(stdout, "Receivers: %u\n", sofa->R);
 340     fprintf(stdout, "Emitters: %u\n", sofa->E);
 341     fprintf(stdout, "Samples: %u\n", sofa->N);
 342
 343     PrintSofaArray("SampleRate", &sofa->DataSamplingRate);
 344     PrintSofaArray("DataDelay", &sofa->DataDelay);
 345
 346     PrintCompatibleLayout(sofa->M, sofa->SourcePosition.values);
 347 }
 348
 349 int main(int argc, char *argv[])
 350 {
 351     GET_UNICODE_ARGS(&argc, &argv);
 352
 353     if(argc != 2)
 354     {
 355         fprintf(stdout, "Usage: %s <sofa-file>\n", argv[0]);
 356         return 0;
 357     }
 358
 359     SofaInfo(argv[1]);
 360
 361     return 0;
 362 }
 363