Developer CD Series 1994 September: Reference Library

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/ Developer CD Series 1994…tember: Reference Library / Dev.CD Sep 94.toast / Periodicals / develop / develop Issue 11 / develop 11 code / MultiBuffer / MultiBuffer Source / AIFFGoodies.c next >

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C/C++ Source or Header | 1992-07-15 | 15.0 KB | 405 lines | [TEXT/MPS ]

/* ** AIFFGoodies ** ** This module contains the routines that pertian to opening, reading and otherwise dealing ** with AIFF Files ** ** (NMD) 9/16/91 created ** (NMD) 9/16/91 OpenAIFFFile ** (NMD) 9/16/91 GetAIFFHeaderInfo ** • Changed to take the paramBlock as an argument and return a long ** indicating the total length of the AIFF data. ** (NMD) 9/20/91 Fixed GetAIFFHeaderInfo to (properly) deal with only 8 bit monophonic samples. ** (NMD) 10/3/91 Changed GetAIFFHeaderInfo so it doesn't stomp on the samplePtr & lenght... ** (NMD) 11/29/91 RecordAIFFFile allows you to record an aiff file to disk... */ #pragma load "MacHeaders" #include <FixMath.h> #ifndef __MAININCLUDES__ #include "MainApp.h" #endif #define kChunkBufferSize 128 #define kChunkHeaderSize 8 enum { // Sample sizes k8bits = 8, k16bits = 16, k24bits = 24, k32bits = 32 }; // these are bit positions for a long flag #define kFORM (1<<0) #define kFormatVersion (1<<1) #define kCommon (1<<2) #define kSoundData (1<<3) #define kMarker (1<<4) #define kInstrument (1<<5) #define kMIDIData (1<<6) #define kAudioRecording (1<<7) #define kApplicationSpecific (1<<8) #define kComment (1<<9) #define kName (1<<10) #define kAuthor (1<<12) #define kCopyright (1<<13) #define kAnnotation (1<<14) typedef union { ChunkHeader generic; ContainerChunk container; FormatVersionChunk formatVersion; CommonChunk common; ExtCommonChunk extCommon; SoundDataChunk soundData; MarkerChunk marker; InstrumentChunk instrument; MIDIDataChunk midiData; AudioRecordingChunk audioRecording; CommentsChunk comments; TextChunk text; } ChunkTemplate, *ChunkTemplatePtr; // // Given an AIFF File gets the sample rate and other relavent pieces of information. // Leaves the file mark at the beginning of the AIFF Sound Data Chunk. Please note // that I'm placing some pretty severe restrictions on the types of samples that this // will actually deal with - 8 bit monophonic, to be more specific... // long GetAIFFHeaderInfo (short frefNum, SoundHeaderPtr theHeader) { OSErr err; // error container long filePosition; // current position in file long dataStart = 0; // where snd data starts long dataSize = 0; // how big snd data is long byteCount; // # if bytes to get from file char chunkBuffer[kChunkBufferSize]; // buffer for chunk data unsigned short chunkFlags = 0; // remember chunks we've seen ChunkTemplatePtr template; // ...for ease of access // Keep track of the beginning of the file err = GetFPos (frefNum, &filePosition); Assert ((err != noErr), "\pCouldn't get file position"); // Now for the fun part ! We're going to assume that these are generic, non-compressed // AIFF files and parse accordingly... do { // Position ourselves at the beginning of the next chunk and read in // a hunk-o-data... err = SetFPos (frefNum, fsFromStart, filePosition); Assert ((err != noErr), "\pCouldn't set file position"); if (err != noErr) break; byteCount = kChunkBufferSize; err = FSRead (frefNum, &byteCount, chunkBuffer); // read a chunk Assert ((err != noErr && err != eofErr), "\pBombed out reading file"); if ( (err != noErr) && (err != eofErr) ) break; // Now, position the template over the data... template = (ChunkTemplatePtr) chunkBuffer; // assume a failure and break out of the do {} while loop if the next case isn't found. // if the case is found and no other error is detected, then each case needs to set noErr err = badFileFormat; switch (template->generic.ckID) { case FORMID : // Format Version Chunk? DebugMessage ("\pfound the form chunk"); Assert ((chunkFlags & kFORM), "\pOH NO!! Found a duplicate FORM Chunk!!"); Assert ((template->container.formType != AIFFID), "\pthis isn't a non-compressed AIFF file"); // make sure that this is a standard, noncompressed AIFF file. if ( !(chunkFlags & kFORM) && (template->container.formType == AIFFID) ) { // see if this chunk already exists chunkFlags |= kFORM; // otherwise mark it found // filePosition += template->container.ckSize + kChunkHeaderSize; // calculate next chunk's position filePosition += 12; err = noErr; } break; case FormatVersionID : // Format Version Chunk? DebugMessage ("\pfound the container chunk"); Assert ((chunkFlags & kFormatVersion), "\pOH NO!! Found a duplicate format version Chunk!!"); if ( !(chunkFlags & kFormatVersion) ) { // see if this chunk already exists chunkFlags |= kFormatVersion; // otherwise mark it found filePosition += template->formatVersion.ckSize + kChunkHeaderSize; // calculate next chunk's position err = noErr; } break; case CommonID : DebugMessage ("\pfound the common chunk"); Assert ((chunkFlags & kCommon), "\pOH NO!! Found a duplicate common Chunk!!"); Assert ((template->common.numChannels != 1), "\pToo many channels"); Assert ((template->common.sampleSize != k8bits), "\pWrong sample size"); if ( !(chunkFlags & kCommon) && (template->common.numChannels == 1) && (template->common.sampleSize == k8bits)) { // see if this chunk already exists chunkFlags |= kCommon; // otherwise mark it found filePosition += template->common.ckSize + kChunkHeaderSize; // calculate next chunk's position // Now that we theoretically have all the relavant information, put it into a header the sound manager // can deal with. Note that we're not returning the length of the file in theHeader->length, because it is // EXTREMELY unlikely that the AIFF file is small enough to feed the SM without resorting to multiple buffers. // • Note that we're not modifying the header's samplePtr or lenght, cause those may contain valid entries!! theHeader->sampleRate = X2Fix (template->common.sampleRate); theHeader->loopStart = 0; theHeader->loopEnd = 0; theHeader->encode = 0; theHeader->baseFrequency = 60; // Perhaps some explanation is in order here: we're interested in how many bytes of data we're going to // be dealing with later on. Since AIFF is interleaved, multiply the number of channels present by // the number of frames in the sample, by the number of bits per sample. Divide by 8 bits/byte and // you done got the number of bytes. So a stereo 8 bit sample actually looks like this: // // |------------- frame 1 -----------| |------------- frame 2 -----------| ... // // [{ch1 sample pt 1} {ch2 sample pt 1}] [{ch1 sample pt 2} {ch2 sample pt 2}] ... dataSize = (template->common.numChannels * template->common.numSampleFrames * template->common.sampleSize) / 8; err = noErr; } break; case SoundDataID: DebugMessage ("\pfound the sound chunk"); Assert ((chunkFlags & kSoundData), "\pOH NO!! Found a duplicate sound data Chunk!!"); if ( !(chunkFlags & kSoundData) ) { // see if this chunk already exists // Let's remember where the Sound Data starts, so we can find the position in the file later. // The mark will be positioned at the beginning of the chunk, so move 16 bytes past to get past // the header information to the data. dataStart = filePosition + 16; chunkFlags |= kSoundData; // otherwise mark it found filePosition += template->soundData.ckSize + kChunkHeaderSize; // calculate next chunk's position err = noErr; } break; // // The following list of chunks we don't care about, so we'll just skip over them. // case MarkerID: DebugMessage ("\pfound a marker chunk"); Assert ((chunkFlags & kMarker), "\pOH NO!! Found a duplicate marker Chunk!!"); if ( !(chunkFlags & kMarker) ) { // see if this chunk already exists chunkFlags |= kMarker; // otherwise mark it found filePosition += template->marker.ckSize + kChunkHeaderSize; // calculate next chunk's position err = noErr; } break; case CommentID: DebugMessage ("\pfound a comment chunk"); Assert ((chunkFlags & kComment), "\pOH NO!! Found a duplicate comment Chunk!!"); if ( !(chunkFlags & kComment) ) { // see if this chunk already exists chunkFlags |= kComment; // otherwise mark it found filePosition += template->marker.ckSize + kChunkHeaderSize; // calculate next chunk's position err = noErr; } break; case InstrumentID: DebugMessage ("\pfound an instrument chunk"); Assert ((chunkFlags & kInstrument), "\pOH NO!! Found a duplicate instrument Chunk!!"); if ( !(chunkFlags & kInstrument) ) { // see if this chunk already exists chunkFlags |= kInstrument; // otherwise mark it found filePosition += template->instrument.ckSize + kChunkHeaderSize; // calculate next chunk's position err = noErr; } break; case MIDIDataID: DebugMessage ("\pfound a MIDI Data chunk"); Assert ((chunkFlags & kMIDIData), "\pOH NO!! Found a duplicate MIDI Chunk!!"); if ( !(chunkFlags & kMIDIData) ) { // see if this chunk already exists chunkFlags |= kMIDIData; // otherwise mark it found filePosition += template->midiData.ckSize + kChunkHeaderSize; // calculate next chunk's position err = noErr; } break; case AudioRecordingID: DebugMessage ("\pfound an audio recording chunk"); Assert ((chunkFlags & kAudioRecording), "\pOH NO!! Found a duplicate Audio Recording Chunk!!"); if ( !(chunkFlags & kAudioRecording) ) { // see if this chunk already exists chunkFlags |= kAudioRecording; // otherwise mark it found filePosition += template->audioRecording.ckSize + kChunkHeaderSize; // calculate next chunk's position err = noErr; } break; case ApplicationSpecificID: DebugMessage ("\pfound an application specifi chunk"); Assert ((chunkFlags & kApplicationSpecific), "\pOH NO!! Found a duplicate application specific Chunk!!"); if ( !(chunkFlags & kApplicationSpecific) ) { // see if this chunk already exists chunkFlags |= kApplicationSpecific; // otherwise mark it found filePosition += template->generic.ckSize + kChunkHeaderSize; // calculate next chunk's position err = noErr; } break; case NameID: DebugMessage ("\pfound a name chunk"); Assert ((chunkFlags & kName), "\pOH NO!! Found a duplicate name Chunk!!"); if ( !(chunkFlags & kName) ) { // see if this chunk already exists chunkFlags |= kName; // otherwise mark it found filePosition += template->generic.ckSize + kChunkHeaderSize; // calculate next chunk's position err = noErr; } break; case AuthorID: DebugMessage ("\pfound an author chunk"); Assert ((chunkFlags & kAuthor), "\pOH NO!! Found a duplicate author Chunk!!"); if ( !(chunkFlags & kAuthor) ) { // see if this chunk already exists chunkFlags |= kAuthor; // otherwise mark it found filePosition += template->generic.ckSize + kChunkHeaderSize; // calculate next chunk's position err = noErr; } break; case CopyrightID: DebugMessage ("\pfound a copyright chunk"); Assert ((chunkFlags & kCopyright), "\pOH NO!! Found a duplicate copyright Chunk!!"); if ( !(chunkFlags & kCopyright) ) { // see if this chunk already exists chunkFlags |= kCopyright; // otherwise mark it found filePosition += template->generic.ckSize + kChunkHeaderSize; // calculate next chunk's position err = noErr; } break; case AnnotationID: DebugMessage ("\pfound an uninteresting chunk"); Assert ((chunkFlags & kAnnotation), "\pOH NO!! Found a duplicate annotation Chunk!!"); if ( !(chunkFlags & kAnnotation) ) { // see if this chunk already exists chunkFlags |= kAnnotation; // otherwise mark it found filePosition += template->generic.ckSize + kChunkHeaderSize; // calculate next chunk's position err = noErr; } break; default : // Unrecognized?? croak. Assert (true, "\pran into an undefined chunk!!"); // If we hit an unrecognized chunk, clear chunkFlags to drop out of the loop // with the assumed error code. chunkFlags = 0; break; } // We're only done when the the FORM, FormatVersion, Common and Sound Data chunks. This is only // true of this incarnation - your needs may vary, so you'll have to modify the following statement // accordingly... // I know, this clause is a pain in the ass: what it really says is this: // As long as we have a FORM Chunk and we don't have all of the {Formatversion, Common, SoundData} chunks // keep going... AND we haven't gotten an error from the file system. } while ( (chunkFlags & kFORM) && (!(chunkFlags & kCommon) || !(chunkFlags & kSoundData)) && (err == noErr) ); // If we completed normally, Position the mark at the beginning of the sound data if (chunkFlags && (err == noErr) ) { err = SetFPos (frefNum, fsFromStart, dataStart); // move mark to data start Assert ((err != noErr), "\pSetFPos failed"); } if (err != noErr) dataSize = 0; // signal a failure return (dataSize); } // // Records from the currently selected sound input device into a file. // The error you get back can be from standardfile, file manager or the sound manager // OSErr RecordAIFFFile (OSType creator) { short fRefNum; OSErr err; Point here; StandardFileReply sReply; StandardPutFile ("\pRecord to:", "\pNew AIFF File", &sReply); Assert ((!sReply.sfGood), "\pFailed in standardfile"); if (sReply.sfGood) { // Valid file selected? // Standard file survived the user!! Decide if the file exists or needs to be created if (sReply.sfReplacing) { err = FSpDelete (&sReply.sfFile); Assert (err, "\pCouldn't delete existing file"); } // Now create a new file and then open it... err = FSpCreate (&sReply.sfFile, creator, 'AIFF',iuSystemScript); Assert (err, "\pCouldn't create file"); if (err == noErr) { err = FSpOpenDF (&sReply.sfFile, fsRdWrPerm, &fRefNum); Assert (err, "\pCouldn't open file"); } } else err = userCanceledErr; // No! return error... if (err == noErr) { // record to the file using the highest level routines available. This gives // us a ready made user interface.... here.h = 30; here.v = 30; err = SndRecordToFile(nil, here, siBestQuality, fRefNum); Assert (err, "\pBombed out recording..."); // Now that we're done (for better or for worse) close the file... FSClose (fRefNum); } return (err); }