libs/appleutility/CAStreamBasicDescription.cpp

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  38 /*=============================================================================
  39         CAStreamBasicDescription.cpp
  40
  41 =============================================================================*/
  42
  43 #include "CAConditionalMacros.h"
  44
  45 #include "CAStreamBasicDescription.h"
  46 #include "CAMath.h"
  47
  48 #if !defined(__COREAUDIO_USE_FLAT_INCLUDES__)
  49         #include <CoreFoundation/CFByteOrder.h>
  50 #else
  51         #include <CFByteOrder.h>
  52 #endif
  53
  54 #pragma mark    This file needs to compile on more earlier versions of the OS, so please keep that in mind when editing it
  55
  56 const AudioStreamBasicDescription       CAStreamBasicDescription::sEmpty = { 0.0, 0, 0, 0, 0, 0, 0, 0, 0 };
  57
  58 CAStreamBasicDescription::CAStreamBasicDescription(double inSampleRate,         UInt32 inFormatID,
  59                                                                         UInt32 inBytesPerPacket,        UInt32 inFramesPerPacket,
  60                                                                         UInt32 inBytesPerFrame,         UInt32 inChannelsPerFrame,
  61                                                                         UInt32 inBitsPerChannel,        UInt32 inFormatFlags)
  62 {
  63         mSampleRate = inSampleRate;
  64         mFormatID = inFormatID;
  65         mBytesPerPacket = inBytesPerPacket;
  66         mFramesPerPacket = inFramesPerPacket;
  67         mBytesPerFrame = inBytesPerFrame;
  68         mChannelsPerFrame = inChannelsPerFrame;
  69         mBitsPerChannel = inBitsPerChannel;
  70         mFormatFlags = inFormatFlags;
  71 }
  72
  73 void CAStreamBasicDescription::PrintFormat(FILE *f, const char *indent, const char *name) const
  74 {
  75         fprintf(f, "%s%s ", indent, name);
  76         char formatID[5];
  77         *(UInt32 *)formatID = CFSwapInt32HostToBig(mFormatID);
  78         formatID[4] = '\0';
  79         fprintf(f, "%2ld ch, %6.0f Hz, '%-4.4s' (0x%08lX) ",
  80                                 NumberChannels(), mSampleRate, formatID,
  81                                 mFormatFlags);
  82         if (mFormatID == kAudioFormatLinearPCM) {
  83                 bool isInt = !(mFormatFlags & kLinearPCMFormatFlagIsFloat);
  84                 int wordSize = SampleWordSize();
  85                 const char *endian = (wordSize > 1) ?
  86                         ((mFormatFlags & kLinearPCMFormatFlagIsBigEndian) ? " big-endian" : " little-endian" ) : "";
  87                 const char *sign = isInt ?
  88                         ((mFormatFlags & kLinearPCMFormatFlagIsSignedInteger) ? " signed" : " unsigned") : "";
  89                 const char *floatInt = isInt ? "integer" : "float";
  90                 char packed[32];
  91                 if (wordSize > 0 && PackednessIsSignificant()) {
  92                         if (mFormatFlags & kLinearPCMFormatFlagIsPacked)
  93                                 sprintf(packed, "packed in %d bytes", wordSize);
  94                         else
  95                                 sprintf(packed, "unpacked in %d bytes", wordSize);
  96                 } else
  97                         packed[0] = '\0';
  98                 const char *align = (wordSize > 0 && AlignmentIsSignificant()) ?
  99                         ((mFormatFlags & kLinearPCMFormatFlagIsAlignedHigh) ? " high-aligned" : " low-aligned") : "";
 100                 const char *deinter = (mFormatFlags & kAudioFormatFlagIsNonInterleaved) ? ", deinterleaved" : "";
 101                 const char *commaSpace = (packed[0]!='\0') || (align[0]!='\0') ? ", " : "";
 102
 103                 fprintf(f, "%ld-bit%s%s %s%s%s%s%s\n",
 104                         mBitsPerChannel, endian, sign, floatInt,
 105                         commaSpace, packed, align, deinter);
 106         } else if (mFormatID == 'alac') {       //      kAudioFormatAppleLossless
 107                 int sourceBits = 0;
 108                 switch (mFormatFlags)
 109                 {
 110                         case 1: //      kAppleLosslessFormatFlag_16BitSourceData
 111                                 sourceBits = 16;
 112                                 break;
 113                 case 2: //      kAppleLosslessFormatFlag_20BitSourceData
 114                         sourceBits = 20;
 115                         break;
 116                 case 3: //      kAppleLosslessFormatFlag_24BitSourceData
 117                         sourceBits = 24;
 118                         break;
 119                 case 4: //      kAppleLosslessFormatFlag_32BitSourceData
 120                         sourceBits = 32;
 121                         break;
 122                 }
 123                 if (sourceBits)
 124                         fprintf(f, "from %d-bit source, ", sourceBits);
 125                 else
 126                         fprintf(f, "from UNKNOWN source bit depth, ");
 127
 128                 fprintf(f, "%ld frames/packet\n", mFramesPerPacket);
 129         }
 130         else
 131                 fprintf(f, "%ld bits/channel, %ld bytes/packet, %ld frames/packet, %ld bytes/frame\n",
 132                         mBitsPerChannel, mBytesPerPacket, mFramesPerPacket, mBytesPerFrame);
 133 }
 134
 135 void    CAStreamBasicDescription::NormalizeLinearPCMFormat(AudioStreamBasicDescription& ioDescription)
 136 {
 137         //  the only thing that changes is to make mixable linear PCM into the canonical linear PCM format
 138         if((ioDescription.mFormatID == kAudioFormatLinearPCM) && ((ioDescription.mFormatFlags & kIsNonMixableFlag) == 0))
 139         {
 140                 //  the canonical linear PCM format is 32 bit native endian floats
 141                 ioDescription.mFormatFlags = kAudioFormatFlagsNativeFloatPacked;
 142                 ioDescription.mBytesPerPacket = sizeof(Float32) * ioDescription.mChannelsPerFrame;
 143                 ioDescription.mFramesPerPacket = 1;
 144                 ioDescription.mBytesPerFrame = sizeof(Float32) * ioDescription.mChannelsPerFrame;
 145                 ioDescription.mBitsPerChannel = 8 * sizeof(Float32);
 146         }
 147 }
 148
 149 void    CAStreamBasicDescription::ResetFormat(AudioStreamBasicDescription& ioDescription)
 150 {
 151         ioDescription.mSampleRate = 0;
 152         ioDescription.mFormatID = 0;
 153         ioDescription.mBytesPerPacket = 0;
 154         ioDescription.mFramesPerPacket = 0;
 155         ioDescription.mBytesPerFrame = 0;
 156         ioDescription.mChannelsPerFrame = 0;
 157         ioDescription.mBitsPerChannel = 0;
 158         ioDescription.mFormatFlags = 0;
 159 }
 160
 161 void    CAStreamBasicDescription::FillOutFormat(AudioStreamBasicDescription& ioDescription, const AudioStreamBasicDescription& inTemplateDescription)
 162 {
 163         if(fiszero(ioDescription.mSampleRate))
 164         {
 165                 ioDescription.mSampleRate = inTemplateDescription.mSampleRate;
 166         }
 167         if(ioDescription.mFormatID == 0)
 168         {
 169                 ioDescription.mFormatID = inTemplateDescription.mFormatID;
 170         }
 171         if(ioDescription.mFormatFlags == 0)
 172         {
 173                 ioDescription.mFormatFlags = inTemplateDescription.mFormatFlags;
 174         }
 175         if(ioDescription.mBytesPerPacket == 0)
 176         {
 177                 ioDescription.mBytesPerPacket = inTemplateDescription.mBytesPerPacket;
 178         }
 179         if(ioDescription.mFramesPerPacket == 0)
 180         {
 181                 ioDescription.mFramesPerPacket = inTemplateDescription.mFramesPerPacket;
 182         }
 183         if(ioDescription.mBytesPerFrame == 0)
 184         {
 185                 ioDescription.mBytesPerFrame = inTemplateDescription.mBytesPerFrame;
 186         }
 187         if(ioDescription.mChannelsPerFrame == 0)
 188         {
 189                 ioDescription.mChannelsPerFrame = inTemplateDescription.mChannelsPerFrame;
 190         }
 191         if(ioDescription.mBitsPerChannel == 0)
 192         {
 193                 ioDescription.mBitsPerChannel = inTemplateDescription.mBitsPerChannel;
 194         }
 195 }
 196
 197 void    CAStreamBasicDescription::GetSimpleName(const AudioStreamBasicDescription& inDescription, char* outName, bool inAbbreviate)
 198 {
 199         switch(inDescription.mFormatID)
 200         {
 201                 case kAudioFormatLinearPCM:
 202                         {
 203                                 const char* theEndianString = NULL;
 204                                 if((inDescription.mFormatFlags & kAudioFormatFlagIsBigEndian) != 0)
 205                                 {
 206                                         #if     TARGET_RT_LITTLE_ENDIAN
 207                                                 theEndianString = "Big Endian";
 208                                         #endif
 209                                 }
 210                                 else
 211                                 {
 212                                         #if     TARGET_RT_BIG_ENDIAN
 213                                                 theEndianString = "Little Endian";
 214                                         #endif
 215                                 }
 216
 217                                 const char* theKindString = NULL;
 218                                 if((inDescription.mFormatFlags & kAudioFormatFlagIsFloat) != 0)
 219                                 {
 220                                         theKindString = (inAbbreviate ? "Float" : "Floating Point");
 221                                 }
 222                                 else if((inDescription.mFormatFlags & kAudioFormatFlagIsSignedInteger) != 0)
 223                                 {
 224                                         theKindString = (inAbbreviate ? "SInt" : "Signed Integer");
 225                                 }
 226                                 else
 227                                 {
 228                                         theKindString = (inAbbreviate ? "UInt" : "Unsigned Integer");
 229                                 }
 230
 231                                 const char* thePackingString = NULL;
 232                                 if((inDescription.mFormatFlags & kAudioFormatFlagIsPacked) == 0)
 233                                 {
 234                                         if((inDescription.mFormatFlags & kAudioFormatFlagIsAlignedHigh) != 0)
 235                                         {
 236                                                 thePackingString = "High";
 237                                         }
 238                                         else
 239                                         {
 240                                                 thePackingString = "Low";
 241                                         }
 242                                 }
 243
 244                                 const char* theMixabilityString = NULL;
 245                                 if((inDescription.mFormatFlags & kIsNonMixableFlag) == 0)
 246                                 {
 247                                         theMixabilityString = "Mixable";
 248                                 }
 249                                 else
 250                                 {
 251                                         theMixabilityString = "Unmixable";
 252                                 }
 253
 254                                 if(inAbbreviate)
 255                                 {
 256                                         if(theEndianString != NULL)
 257                                         {
 258                                                 if(thePackingString != NULL)
 259                                                 {
 260                                                         sprintf(outName, "%s %d Ch %s %s %s%d/%s%d", theMixabilityString, (int)inDescription.mChannelsPerFrame, theEndianString, thePackingString, theKindString, (int)inDescription.mBitsPerChannel, theKindString, (int)(inDescription.mBytesPerFrame / inDescription.mChannelsPerFrame) * 8);
 261                                                 }
 262                                                 else
 263                                                 {
 264                                                         sprintf(outName, "%s %d Ch %s %s%d", theMixabilityString, (int)inDescription.mChannelsPerFrame, theEndianString, theKindString, (int)inDescription.mBitsPerChannel);
 265                                                 }
 266                                         }
 267                                         else
 268                                         {
 269                                                 if(thePackingString != NULL)
 270                                                 {
 271                                                         sprintf(outName, "%s %d Ch %s %s%d/%s%d", theMixabilityString, (int)inDescription.mChannelsPerFrame, thePackingString, theKindString, (int)inDescription.mBitsPerChannel, theKindString, (int)((inDescription.mBytesPerFrame / inDescription.mChannelsPerFrame) * 8));
 272                                                 }
 273                                                 else
 274                                                 {
 275                                                         sprintf(outName, "%s %d Ch %s%d", theMixabilityString, (int)inDescription.mChannelsPerFrame, theKindString, (int)inDescription.mBitsPerChannel);
 276                                                 }
 277                                         }
 278                                 }
 279                                 else
 280                                 {
 281                                         if(theEndianString != NULL)
 282                                         {
 283                                                 if(thePackingString != NULL)
 284                                                 {
 285                                                         sprintf(outName, "%s %d Channel %d Bit %s %s Aligned %s in %d Bits", theMixabilityString, (int)inDescription.mChannelsPerFrame, (int)inDescription.mBitsPerChannel, theEndianString, theKindString, thePackingString, (int)(inDescription.mBytesPerFrame / inDescription.mChannelsPerFrame) * 8);
 286                                                 }
 287                                                 else
 288                                                 {
 289                                                         sprintf(outName, "%s %d Channel %d Bit %s %s", theMixabilityString, (int)inDescription.mChannelsPerFrame, (int)inDescription.mBitsPerChannel, theEndianString, theKindString);
 290                                                 }
 291                                         }
 292                                         else
 293                                         {
 294                                                 if(thePackingString != NULL)
 295                                                 {
 296                                                         sprintf(outName, "%s %d Channel %d Bit %s Aligned %s in %d Bits", theMixabilityString, (int)inDescription.mChannelsPerFrame, (int)inDescription.mBitsPerChannel, theKindString, thePackingString, (int)(inDescription.mBytesPerFrame / inDescription.mChannelsPerFrame) * 8);
 297                                                 }
 298                                                 else
 299                                                 {
 300                                                         sprintf(outName, "%s %d Channel %d Bit %s", theMixabilityString, (int)inDescription.mChannelsPerFrame, (int)inDescription.mBitsPerChannel, theKindString);
 301                                                 }
 302                                         }
 303                                 }
 304                         }
 305                         break;
 306
 307                 case kAudioFormatAC3:
 308                         strcpy(outName, "AC-3");
 309                         break;
 310
 311                 case kAudioFormat60958AC3:
 312                         strcpy(outName, "AC-3 for SPDIF");
 313                         break;
 314
 315                 default:
 316                         {
 317                                 char* the4CCString = (char*)&inDescription.mFormatID;
 318                                 outName[0] = the4CCString[0];
 319                                 outName[1] = the4CCString[1];
 320                                 outName[2] = the4CCString[2];
 321                                 outName[3] = the4CCString[3];
 322                                 outName[4] = 0;
 323                         }
 324                         break;
 325         };
 326 }
 327
 328 #if CoreAudio_Debug
 329 #include "CALogMacros.h"
 330
 331 void    CAStreamBasicDescription::PrintToLog(const AudioStreamBasicDescription& inDesc)
 332 {
 333         PrintFloat              ("  Sample Rate:        ", inDesc.mSampleRate);
 334         Print4CharCode  ("  Format ID:          ", inDesc.mFormatID);
 335         PrintHex                ("  Format Flags:       ", inDesc.mFormatFlags);
 336         PrintInt                ("  Bytes per Packet:   ", inDesc.mBytesPerPacket);
 337         PrintInt                ("  Frames per Packet:  ", inDesc.mFramesPerPacket);
 338         PrintInt                ("  Bytes per Frame:    ", inDesc.mBytesPerFrame);
 339         PrintInt                ("  Channels per Frame: ", inDesc.mChannelsPerFrame);
 340         PrintInt                ("  Bits per Channel:   ", inDesc.mBitsPerChannel);
 341 }
 342 #endif
 343
 344 bool    operator<(const AudioStreamBasicDescription& x, const AudioStreamBasicDescription& y)
 345 {
 346         bool theAnswer = false;
 347         bool isDone = false;
 348
 349         //      note that if either side is 0, that field is skipped
 350
 351         //      format ID is the first order sort
 352         if((!isDone) && ((x.mFormatID != 0) && (y.mFormatID != 0)))
 353         {
 354                 if(x.mFormatID != y.mFormatID)
 355                 {
 356                         //      formats are sorted numerically except that linear
 357                         //      PCM is always first
 358                         if(x.mFormatID == kAudioFormatLinearPCM)
 359                         {
 360                                 theAnswer = true;
 361                         }
 362                         else if(y.mFormatID == kAudioFormatLinearPCM)
 363                         {
 364                                 theAnswer = false;
 365                         }
 366                         else
 367                         {
 368                                 theAnswer = x.mFormatID < y.mFormatID;
 369                         }
 370                         isDone = true;
 371                 }
 372         }
 373
 374
 375         //  mixable is always better than non-mixable for linear PCM and should be the second order sort item
 376         if((!isDone) && ((x.mFormatID == kAudioFormatLinearPCM) && (y.mFormatID == kAudioFormatLinearPCM)))
 377         {
 378                 if(((x.mFormatFlags & kIsNonMixableFlag) == 0) && ((y.mFormatFlags & kIsNonMixableFlag) != 0))
 379                 {
 380                         theAnswer = true;
 381                         isDone = true;
 382                 }
 383                 else if(((x.mFormatFlags & kIsNonMixableFlag) != 0) && ((y.mFormatFlags & kIsNonMixableFlag) == 0))
 384                 {
 385                         theAnswer = false;
 386                         isDone = true;
 387                 }
 388         }
 389
 390         //      floating point vs integer for linear PCM only
 391         if((!isDone) && ((x.mFormatID == kAudioFormatLinearPCM) && (y.mFormatID == kAudioFormatLinearPCM)))
 392         {
 393                 if((x.mFormatFlags & kAudioFormatFlagIsFloat) != (y.mFormatFlags & kAudioFormatFlagIsFloat))
 394                 {
 395                         //      floating point is better than integer
 396                         theAnswer = y.mFormatFlags & kAudioFormatFlagIsFloat;
 397                         isDone = true;
 398                 }
 399         }
 400
 401         //      bit depth
 402         if((!isDone) && ((x.mBitsPerChannel != 0) && (y.mBitsPerChannel != 0)))
 403         {
 404                 if(x.mBitsPerChannel != y.mBitsPerChannel)
 405                 {
 406                         //      deeper bit depths are higher quality
 407                         theAnswer = x.mBitsPerChannel < y.mBitsPerChannel;
 408                         isDone = true;
 409                 }
 410         }
 411
 412         //      sample rate
 413         if((!isDone) && fnonzero(x.mSampleRate) && fnonzero(y.mSampleRate))
 414         {
 415                 if(fnotequal(x.mSampleRate, y.mSampleRate))
 416                 {
 417                         //      higher sample rates are higher quality
 418                         theAnswer = x.mSampleRate < y.mSampleRate;
 419                         isDone = true;
 420                 }
 421         }
 422
 423         //      number of channels
 424         if((!isDone) && ((x.mChannelsPerFrame != 0) && (y.mChannelsPerFrame != 0)))
 425         {
 426                 if(x.mChannelsPerFrame != y.mChannelsPerFrame)
 427                 {
 428                         //      more channels is higher quality
 429                         theAnswer = x.mChannelsPerFrame < y.mChannelsPerFrame;
 430                         isDone = true;
 431                 }
 432         }
 433
 434         return theAnswer;
 435 }
 436
 437 static bool MatchFormatFlags(const AudioStreamBasicDescription& x, const AudioStreamBasicDescription& y)
 438 {
 439         UInt32 xFlags = x.mFormatFlags;
 440         UInt32 yFlags = y.mFormatFlags;
 441
 442         // match wildcards
 443         if (x.mFormatID == 0 || y.mFormatID == 0 || xFlags == 0 || yFlags == 0)
 444                 return true;
 445
 446         if (x.mFormatID == kAudioFormatLinearPCM)
 447         {
 448                 // knock off the all clear flag
 449                 xFlags = xFlags & ~kAudioFormatFlagsAreAllClear;
 450                 yFlags = yFlags & ~kAudioFormatFlagsAreAllClear;
 451
 452                 // if both kAudioFormatFlagIsPacked bits are set, then we don't care about the kAudioFormatFlagIsAlignedHigh bit.
 453                 if (xFlags & yFlags & kAudioFormatFlagIsPacked) {
 454                         xFlags = xFlags & ~kAudioFormatFlagIsAlignedHigh;
 455                         yFlags = yFlags & ~kAudioFormatFlagIsAlignedHigh;
 456                 }
 457
 458                 // if both kAudioFormatFlagIsFloat bits are set, then we don't care about the kAudioFormatFlagIsSignedInteger bit.
 459                 if (xFlags & yFlags & kAudioFormatFlagIsFloat) {
 460                         xFlags = xFlags & ~kAudioFormatFlagIsSignedInteger;
 461                         yFlags = yFlags & ~kAudioFormatFlagIsSignedInteger;
 462                 }
 463
 464                 //      if the bit depth is 8 bits or less and the format is packed, we don't care about endianness
 465                 if((x.mBitsPerChannel <= 8) && ((xFlags & kAudioFormatFlagIsPacked) == kAudioFormatFlagIsPacked))
 466                 {
 467                         xFlags = xFlags & ~kAudioFormatFlagIsBigEndian;
 468                 }
 469                 if((y.mBitsPerChannel <= 8) && ((yFlags & kAudioFormatFlagIsPacked) == kAudioFormatFlagIsPacked))
 470                 {
 471                         yFlags = yFlags & ~kAudioFormatFlagIsBigEndian;
 472                 }
 473
 474                 //      if the number of channels is 0 or 1, we don't care about non-interleavedness
 475                 if (x.mChannelsPerFrame <= 1 && y.mChannelsPerFrame <= 1) {
 476                         xFlags &= ~kLinearPCMFormatFlagIsNonInterleaved;
 477                         yFlags &= ~kLinearPCMFormatFlagIsNonInterleaved;
 478                 }
 479         }
 480         return xFlags == yFlags;
 481 }
 482
 483 bool    operator==(const AudioStreamBasicDescription& x, const AudioStreamBasicDescription& y)
 484 {
 485         //      the semantics for equality are:
 486         //              1) Values must match exactly
 487         //              2) wildcard's are ignored in the comparison
 488
 489 #define MATCH(name) ((x.name) == 0 || (y.name) == 0 || (x.name) == (y.name))
 490
 491         return
 492                         //      check the sample rate
 493                 (fiszero(x.mSampleRate) || fiszero(y.mSampleRate) || fequal(x.mSampleRate, y.mSampleRate))
 494
 495                         //      check the format ids
 496                 && MATCH(mFormatID)
 497
 498                         //      check the format flags
 499                 && MatchFormatFlags(x, y)
 500
 501                         //      check the bytes per packet
 502                 && MATCH(mBytesPerPacket)
 503
 504                         //      check the frames per packet
 505                 && MATCH(mFramesPerPacket)
 506
 507                         //      check the bytes per frame
 508                 && MATCH(mBytesPerFrame)
 509
 510                         //      check the channels per frame
 511                 && MATCH(mChannelsPerFrame)
 512
 513                         //      check the channels per frame
 514                 && MATCH(mBitsPerChannel) ;
 515 }
 516
 517 bool SanityCheck(const AudioStreamBasicDescription& x)
 518 {
 519         return (x.mSampleRate >= 0.);
 520 }