MovieWriter.m

/*
 
File: MovieWriter.m
 
Author: QuickTime DTS
 
Change History (most recent first): 
 
    <3> 09/19/06 modified to perform audio extraction/conversion for QTExtractAndConvertToMovie
    <2> 03/24/06 must pass NSError objects to exportCompleted
    <1> 11/10/05 initial release as part of ExtractMovieAudioToAIFF
 
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*/
 
/*
 
QTExtractAndConvertToMovie contains two Objective-C objects that are used together to
implement audio extraction and audio conversion from a QuickTime Movie's sound track to
an movie file.
 
The first is a simple class called MovieWriter (this is a modified version of the
AIFFWriter class that was included with the ExtractMovieAudioToAIFF and
QTExtractAndConvertToAIFF samples). MovieWriter uses QuickTime's Movie Audio Extraction,
Movie Storage and Media Creation APIs. The second is another simple class called
AudioConverter which encapsulates Core Audio's Audio Converter API.
 
The sample uses an instance of the MovieWriter class to easily set up audio extraction
from a QTKit QTMovie to a new destination Movie and its associated movie file (or movie
storage as it's called in the API). MovieWriter uses an instance of the AudioConverter
class to perform the conversion to a user selected destination format which is
configured by the Standard Audio Dialog Component. The Audio Converter uses a Movie
Audio Extraction Session in the Read Input Procedure to pull audio out of the source
Movie.
 
QTExtractAndConvertToMovie demonstrates how to call AddMediaSample2 and supports VBR as
well as CBR audio encoding formats.
 
NOTE: This sample uses the default extraction channel layout which is the aggregate
channel layout of the Movie (for example, all Rights mixed together, all Left Surrounds
mixed together, etc).
 
References:
 
http://developer.apple.com/documentation/QuickTime/Conceptual/QT7UpdateGuide/Chapter02/chapter_2_section_6.html
 
http://developer.apple.com/documentation/MusicAudio/Conceptual/CoreAudioOverview/WhatsinCoreAudio/chapter_3_section_4.html
 
*/
 
#import "MovieWriter.h"
 
#pragma mark ---- MovieWriterProgressInfo ----
 
// MovieWriterProgressInfo is the object passed back to the progress callback
// if implemented by the client. It contains information regarding the current
// state of the export session which can be used to drive a UI.
@interface MovieWriterProgressInfo (Private)
 
- (BOOL)continueOperation;
- (void)setPhase:(MovieWriterExportOperationPhase)value;
- (void)setProgressValue:(NSNumber *)value;
- (void)setExportStatus:(NSError *)status;
 
@end
 
@implementation MovieWriterProgressInfo
 
- (MovieWriterExportOperationPhase)phase 
{
    return phase;
}
 
- (NSNumber *)progressValue
{
    return [[progressValue retain] autorelease];
}
 
- (NSError *)exportStatus {
    return [[exportStatus retain] autorelease];
}
 
- (BOOL)continueOperation;
{
    return continueOperation;
}
 
- (void)setContinueOperation:(BOOL)value
{
    continueOperation = value;
}
 
- (void)setPhase:(MovieWriterExportOperationPhase)value
{
    phase = value;
}
 
- (void)setProgressValue:(NSNumber *)value
{
    if (progressValue != value) {
        [progressValue release];
        progressValue = [value copy];
    }
}
 
- (void)setExportStatus:(NSError *)status
{
    if (exportStatus != status) {
        [exportStatus release];
        exportStatus = [status copy];
    }
}
 
- (void)dealloc
{
    [progressValue release];
    [exportStatus release];
    
    [super dealloc];
}
 
@end
 
#pragma mark ---- MovieWriter private interface ----
 
@interface MovieWriter (Private)
 
- (void)exportOnMainThreadCallBack:(id)inObject;
- (void)exportOnWorkerThread:(id)inObject;
 
- (OSStatus)convertAudioToFile:(SInt64 *)ioNumFrames;
 
- (OSStatus)configureExtractionSessionWithMovie:(Movie)inMovie;
- (OSStatus)createOutputFile:(AudioStreamBasicDescription *)inOutputASBD;
- (void)setMovieConversionDuration;
 
- (void)exportCompletedNotification:(NSError *)inError;
 
- (MovieAudioExtractionRef)audioExtractionSession;
- (AudioBufferList *)extractionBufferList;
- (UInt32)extractionBytesPerFrame;
- (BOOL)extractionComplete;
- (void)setExtractionComplete:(BOOL)flag;
 
@end
 
@implementation MovieWriter
 
#pragma mark ---- Audio Converter InputDataProc Implementation  ----
 
// Read Input Procedure used to supply data to the Audio Converter
static OSStatus ReadInputProc(AudioConverterRef inAudioConverter,
                              UInt32 *ioNumberDataPackets,
                              AudioBufferList *ioData,
                              AudioStreamPacketDescription **outDataPacketDescription,
                              void *inUserData)
{
#pragma unused(inAudioConverter, outDataPacketDescription)
 
    if (NULL == inUserData) return paramErr;
 
    MovieWriter *theMovieWriter = (MovieWriter *)inUserData;
    
    AudioBufferList *extractionBufferList;
    UInt32 i, flags;
    
    UInt32 numFrames = kMaxExtractionFrameCount;
    UInt32 bytesPerFrame;
    MovieAudioExtractionRef audioExtractionSession;
    
    OSStatus err = noErr;
    
    extractionBufferList = [theMovieWriter extractionBufferList];
    bytesPerFrame = [theMovieWriter extractionBytesPerFrame];
    audioExtractionSession = [theMovieWriter audioExtractionSession];
    
    if (![theMovieWriter extractionComplete]) {
 
        for (i = 0; i < extractionBufferList->mNumberBuffers; i++) {
            extractionBufferList->mBuffers[i].mDataByteSize = numFrames * bytesPerFrame;
        }
        
        // read the number of requested samples from the movie
        // we're using movie audio extraction therefore we know we're supplying pcm so packet descriptions are unnecessary
        err = MovieAudioExtractionFillBuffer(audioExtractionSession, &numFrames, extractionBufferList, &flags);
        
        if (flags & kQTMovieAudioExtractionComplete) {
            [theMovieWriter setExtractionComplete:YES];
        }
            
        *ioNumberDataPackets = numFrames;
        for (i = 0; i < extractionBufferList->mNumberBuffers; i++) {
            ioData->mBuffers[i] = extractionBufferList->mBuffers[i];
        }
    } else {
        *ioNumberDataPackets = 0;
    }
    
    return err;
}
 
#pragma mark ---- initialization/dealocation ----
 
- (id)init;
{
    if (self = [super init]) {
    
        mLock = [[NSLock alloc] init];
        mProgressInfo = [[MovieWriterProgressInfo alloc] init];
    }
 
    return self;
}
 
- (void)dealloc
{
    if (mFileName) {
        [mFileName release];
    }
    
    if (mAudioExtractionSession){
        MovieAudioExtractionEnd(mAudioExtractionSession);
    }
    
    if (mMyAudioConverter) {
        [mMyAudioConverter release];
    }
    
    if (mQTMovie) {
        [mQTMovie release];
    }
    
    if (mSoundDescription) {
        DisposeHandle((Handle)mSoundDescription);
        mSoundDescription = NULL;
    }
    
    if (mExtractionBuffList) {
        free(mExtractionBuffList);
    }
    
    if (mExtractionBuffer) {
        free(mExtractionBuffer);
    }
    
    if (mOutputBufferList) {
        free(mOutputBufferList);
    }
    
    if (mOutputBuffer) {
        free(mOutputBuffer);
    }
    
    if (mPacketDescriptions) {
        free(mPacketDescriptions);
    }
    
    [mLock release];
    
    [mProgressInfo release];
    
    [super dealloc]; 
}
 
#pragma mark ---- public ----
 
// main method call that will produce an output movie file - it will try to
// export the source movie on a separate thread but if it can't will schedule
// callbacks on the main thread
- (OSStatus)exportFromMovie:(QTMovie *)inMovie toFile:(NSString *)inFullPath
{
    BOOL extractionOnWorkerThread = NO;
    BOOL continueExport = YES;
    Handle cloneHandle = NULL;
    FSRef fileRef;
    NSString *directory;
    
    OSStatus err = noErr;
    
    // sanity
    if (nil == inMovie || nil == inFullPath) return paramErr;
    
    // if we're busy already doing an export return
    if (![mLock tryLock]) return kObjectInUseErr;
    
    mIsConverting = YES;
    
    // if the client implemented a progress proc. call it now
    if (TRUE == mDelegateShouldContinueOp) {
        [mProgressInfo setPhase:MovieWriterExportBegin];
        [mProgressInfo setProgressValue:nil];
        [mProgressInfo setExportStatus:nil];
        
        continueExport = [[self delegate] shouldContinueOperationWithProgressInfo:mProgressInfo];
 
        if (NO == continueExport) goto bail;
    }
    
    directory = [inFullPath stringByDeletingLastPathComponent];
    
    mFileName = [[NSString alloc] initWithString:[inFullPath lastPathComponent]];
    
    // retain the QTMovie object passed in, we need it for the duration of
    // the export regardless of what the client decides to do with it
    mQTMovie = [inMovie retain];
    
    // create a new Audio Converter object for this conversion operation
    mMyAudioConverter = [AudioConverter newAudioConverterWithMovie:[mQTMovie quickTimeMovie] status:&err];
    if (NULL == mMyAudioConverter) goto bail;
        
    // set the Audio Converter Read Input Data Proc
    [mMyAudioConverter setInputDataProc:ReadInputProc];
 
    // if the file already exists, delete it
    err = FSPathMakeRef((const UInt8*)[inFullPath fileSystemRepresentation], &fileRef, false);
    if (err == noErr) {
        err = FSDeleteObject(&fileRef);
        if (err) goto bail;
    }
    
    err = FSPathMakeRef((const UInt8*)[directory fileSystemRepresentation], &mParentRef, NULL);
    if (err) goto bail;
    
    // set the movies duration in floating-point seconds
    [self setMovieConversionDuration];
    
    // clone the movie and see if we can migrate it to a worker thread for extraction
    cloneHandle = NewHandle(0);
    if (NULL == cloneHandle) { err = memFullErr; goto bail; }
    
    err = PutMovieIntoHandle([mQTMovie quickTimeMovie], cloneHandle);
    if (err) goto bail;
    
    err = NewMovieFromHandle(&mCloneMovie, cloneHandle, newMovieActive, NULL);
    if (err != noErr || mCloneMovie == NULL) goto bail;
    
    // if we couldn't migrate this movie, export from the movie on the main thread
    if (DetachMovieFromCurrentThread(mCloneMovie) == noErr) {
        extractionOnWorkerThread = YES;
    } else {
        DisposeMovie(mCloneMovie);
        mCloneMovie = NULL;
    }
    
    if (extractionOnWorkerThread == YES) {
        // export on a worker thread if we can...
        [NSThread detachNewThreadSelector:@selector(exportOnWorkerThread:) toTarget:self withObject:nil];
    } else {
        // ...if not, we're on the main thread so just call the main-thread worker method
        [self exportOnMainThreadCallBack:nil];
    }
 
bail:
 
    if (cloneHandle) DisposeHandle(cloneHandle);
    
    if (err) [self exportCompletedNotification:[NSError errorWithDomain:NSOSStatusErrorDomain code:err userInfo:nil]];
    
    return err;
}
 
- (BOOL)isConverting
{
    return mIsConverting;
}
 
#pragma mark ---- private ----
 
// this callback is scheduled on the main thread - In order to keep from locking up the UI,
// it does one slice of export, writes it to file and then reschedule itself
-(void)exportOnMainThreadCallBack:(id)inObject
{
#pragma unused(inObject)
 
    BOOL continueExport = YES;
    
    OSStatus err;
    
    // prepare for extraction if this is the first entry
    if (NULL == mAudioExtractionSession) {
    
        err = [self configureExtractionSessionWithMovie:[mQTMovie quickTimeMovie]];
        if (err) goto bail;
    }
     
    // create the file
    // set the number of total samples to export
    if (0 == mOutputMovieStorageDH) {
        AudioStreamBasicDescription *outputASBD = [mMyAudioConverter outputFormat];
    
        err = [self createOutputFile:outputASBD];
        if (err) goto bail;
        
        mTotalNumberOfOutputFrames = mMovieDuration ? (mMovieDuration * outputASBD->mSampleRate) : -1;
        mOneSegmentOfOutputFrames = (0.50 * outputASBD->mSampleRate);
        
        if (-1 == mTotalNumberOfOutputFrames) { mConversionComplete = YES; err = paramErr; }
    }
    
    // perform conversion
    if (!mConversionComplete) {
    
        // if the client implemented a progress proc. call it now
        if (TRUE == mDelegateShouldContinueOp) {
            NSNumber *progressValue = [NSNumber numberWithFloat:(float)((float)mOutputFramesCompleted / (float)mTotalNumberOfOutputFrames)];
            
            [mProgressInfo setPhase:MovieWriterExportPercent];
            [mProgressInfo setProgressValue:progressValue];
            [mProgressInfo setExportStatus:nil];
            
            continueExport = [[self delegate] shouldContinueOperationWithProgressInfo:mProgressInfo];
            if (NO == continueExport) { err = userCanceledErr; goto bail; }
        }
    
       // convert and write a half-second's worth of data
       SInt64 numFramesThisSlice = mOneSegmentOfOutputFrames;
 
        // extract and convert the audio and write it to the file
        err = [self convertAudioToFile:&numFramesThisSlice];    
        if (err) goto bail;
        
        mOutputFramesCompleted += numFramesThisSlice;
    }
 
bail:
    if (err || mConversionComplete) {
        // we're done so close the file if there was no error or delete the file if we errored out
        
        if (mOutputMovieStorageDH) {
            if (noErr == err) {
                Track soundTrack = GetMediaTrack(mSoundMedia);
                
                err = EndMediaEdits(mSoundMedia);
                if (noErr == err)
                    err = InsertMediaIntoTrack(soundTrack, 0, 0, GetMediaDuration(mSoundMedia), fixed1);
                    if (noErr == err)
                        err = AddMovieToStorage(mOutputMovie, mOutputMovieStorageDH);
                
                if (err) DataHDeleteFile(mOutputMovieStorageDH);
            } else {
                DataHDeleteFile(mOutputMovieStorageDH);
            }
            
            CloseMovieStorage(mOutputMovieStorageDH);
            mOutputMovieStorageDH = 0;
            
            if (mOutputMovie) { DisposeMovie(mOutputMovie); mOutputMovie = 0; }
        }
 
        // call the completion routine to clean up
        [self exportCompletedNotification:[NSError errorWithDomain:NSOSStatusErrorDomain code:err userInfo:nil]];
        
    } else {
    
        // reschedule to perform this routine again on the next run loop cycle
        [self performSelectorOnMainThread:@selector(exportOnMainThreadCallBack:)
                                          withObject:(id)nil
                                          waitUntilDone:NO];
    }
}
 
// this method will be performed on a background thread
- (void)exportOnWorkerThread:(id)inObject
{
#pragma unused(inObject)
 
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
    
    BOOL continueExport = YES;
    
    OSStatus err;
 
    [NSThread setThreadPriority:[NSThread threadPriority]+.1];
    
    // attach the movie to this thread
    err = EnterMoviesOnThread(0);
    if (err) goto bail;;
    
    err = AttachMovieToCurrentThread(mCloneMovie);
    if (err) goto bail;
    
    // prepare extraction session
    if (NULL == mAudioExtractionSession) {
         
        err = [self configureExtractionSessionWithMovie:mCloneMovie];
        if (err) goto done;
    }
     
    // create the file
    if (0 == mOutputMovieStorageDH) {
        AudioStreamBasicDescription *outputASBD = [mMyAudioConverter outputFormat];
    
        err = [self createOutputFile:outputASBD];
        if (err) goto bail;
        
        mTotalNumberOfOutputFrames = mMovieDuration ? (mMovieDuration * outputASBD->mSampleRate) : -1;
        mOneSegmentOfOutputFrames = (5.0 * outputASBD->mSampleRate); // five seconds of audio at a time
        
        if (-1 == mTotalNumberOfOutputFrames) { mConversionComplete = YES; err = paramErr; }
    }
    
    // loop until stopped from an external event, or finished the entire operation
    while (YES == continueExport && NO == mConversionComplete) {
        
        if (!mConversionComplete) {
        
            // if the client implemented a progress proc. call it now we wait for the
            // progress fuction to return before continuing so we can check the return code
            if (TRUE == mDelegateShouldContinueOp) {
                NSNumber *progressValue = [NSNumber numberWithFloat:(float)((float)mOutputFramesCompleted / (float)mTotalNumberOfOutputFrames)];
                
                [mProgressInfo setPhase:MovieWriterExportPercent];
                [mProgressInfo setProgressValue:progressValue];
                [mProgressInfo setExportStatus:nil];
                
                [[self delegate] performSelectorOnMainThread:@selector(shouldContinueOperationWithProgressInfo:)
                                 withObject:(id)mProgressInfo
                                 waitUntilDone:YES];
                
                continueExport = [mProgressInfo continueOperation];
                if (NO == continueExport) { err = userCanceledErr; break; }
            }
        
            // read numSamplesThisSlice number of samples
            SInt64 numFramesThisSlice = mOneSegmentOfOutputFrames;
 
            // extract and convert the audio and write it to the file
            err = [self convertAudioToFile:&numFramesThisSlice];    
            if (err) break;
            
            mOutputFramesCompleted += numFramesThisSlice;
        }
    }
 
done:
 
    // detach the exported movie from this thread
    DetachMovieFromCurrentThread(mCloneMovie);
    ExitMoviesOnThread();
        
    if (mOutputMovieStorageDH) {
        if (noErr == err) {
            Track soundTrack = GetMediaTrack(mSoundMedia);
            
            err = EndMediaEdits(mSoundMedia);
            if (noErr == err)
                err = InsertMediaIntoTrack(soundTrack, 0, 0, GetMediaDuration(mSoundMedia), fixed1);
                if (noErr == err)
                    err = AddMovieToStorage(mOutputMovie, mOutputMovieStorageDH);
            
            if (err) DataHDeleteFile(mOutputMovieStorageDH);
        } else {
            DataHDeleteFile(mOutputMovieStorageDH);
        }
        
        CloseMovieStorage(mOutputMovieStorageDH);
        mOutputMovieStorageDH = 0;
        
        if (mOutputMovie) { DisposeMovie(mOutputMovie); mOutputMovie = 0; }
    }
 
bail:
    // call the completion routine to clean up on the main thread
    [self performSelectorOnMainThread:@selector(exportCompletedNotification:)
                                                withObject:(id)[NSError errorWithDomain:NSOSStatusErrorDomain code:err userInfo:nil]
                                                waitUntilDone:YES];
    
    [pool release];
}
 
// convert a slice of PCM audio and write it to a movie file - we proceed serially
// from the last position, 'ploc' specifies the file offset that the converted buffer should be written to
- (OSStatus)convertAudioToFile:(SInt64 *)ioNumFrames
{   
    UInt32   i;
    UInt32   numFrames, numPackets;
    OSStatus err;
 
    AudioStreamBasicDescription *extractionASBD = [mMyAudioConverter inputFormat];
    AudioStreamBasicDescription *outputASBD = [mMyAudioConverter outputFormat];
    
    // the AudioConverter doesn't seem to like to emit one packet at a time for QDesign/QualComm,
    // so make sure there are at least 2 packets per buffer
    numFrames = *ioNumFrames;
    numPackets = 2 + (numFrames / outputASBD->mFramesPerPacket);
    
    /* First time though we'll need to set up the Extraction Buffer and BufferList
       This is the buffer Movie Audio Extraction is writing into, in other words the source
       buffers for the Audio Converter
       
       We're always pulling non-interleaved buffers of LPCM from Movie Audio Extraction
       
       When working with non-interleaved audio, you need to allocate n buffers of bufferSize,
       and assign each mData to one of them
       
       NOTE - The extraction pull size will always be 4096 is this sample (kMaxExtractionFrameCount)
       
    */    
    if (NULL == mExtractionBuffList) {
    
        mExtractionBufferSize = (kMaxExtractionFrameCount * extractionASBD->mBytesPerFrame);
        mExtractionBuffer = (char *)malloc(mExtractionBufferSize * extractionASBD->mChannelsPerFrame);
        if (NULL == mExtractionBuffer) {
            err = memFullErr;
            goto bail;
        }
        
        mExtractionBuffList = (AudioBufferList *)calloc(1, offsetof(AudioBufferList, mBuffers[extractionASBD->mChannelsPerFrame]));
        if (NULL == mExtractionBuffList) {
            err = memFullErr;
            goto bail;
        }
 
        mExtractionBuffList->mNumberBuffers = extractionASBD->mChannelsPerFrame;
        for (i = 0; i < extractionASBD->mChannelsPerFrame; i++) {
            mExtractionBuffList->mBuffers[i].mNumberChannels = 1;
            mExtractionBuffList->mBuffers[i].mDataByteSize = mExtractionBufferSize;
            mExtractionBuffList->mBuffers[i].mData = &mExtractionBuffer[i * mExtractionBufferSize];
        }       
    }
    
    /* First time though we'll need to set up the Output BufferList
       We're always converting to interleaved data since we're writing to a file
       so one output buffer is all we need
    
    */    
    if (NULL == mOutputBufferList) {
    
        // calculate the output buffer size
        if (0 == outputASBD->mBytesPerPacket) {
            // if bytes per packet value is 0 in the asbd, we will need to use the
            // largest possible packet size - this information is available from the audio converter
            UInt32 propertySize = sizeof(UInt32);
            
            [mMyAudioConverter getProperty:kAudioConverterPropertyMaximumOutputPacketSize: &propertySize: &mMaxPacketSize];
            
            mOutputBufferSize = (numPackets * mMaxPacketSize);
        } else {
            mOutputBufferSize = (numPackets * outputASBD->mBytesPerPacket);
        }
        
        mOutputBuffer = (char *)malloc(mOutputBufferSize);
        if (NULL == mOutputBuffer) {
            err = memFullErr;
            goto bail;
        }
        
        mOutputBufferList = (AudioBufferList *)calloc(1, sizeof(AudioBufferList));
        if (NULL == mOutputBufferList) {
            err = memFullErr;
            goto bail;
        }
        
        // externally framed formats requires packet descriptions
        if ([mMyAudioConverter formatRequiresPacketDescriptions]) {
            
            mPacketDescriptions = (AudioStreamPacketDescription*)calloc(numPackets, sizeof(AudioStreamPacketDescription));
            if (NULL == mPacketDescriptions) {  
                err = memFullErr;
                goto bail;
            }
        }
        
        // tell out custom audio converter class about the output buffer, that's where it's going to put the converted audio
        [mMyAudioConverter setOutputAudioBufferList:mOutputBufferList];
    }
    
    // make sure we don't try to convert more than we allocated room for
    if (0 == outputASBD->mBytesPerPacket) {
        if (numPackets > (mOutputBufferSize / mMaxPacketSize)) {
            numPackets = mOutputBufferSize / mMaxPacketSize;
        }
    } else {
        if (numPackets > (mOutputBufferSize / outputASBD->mBytesPerPacket)) {
            numPackets = mOutputBufferSize / outputASBD->mBytesPerPacket;
        }
    }
    
    // set up the buffer list each time through
    mOutputBufferList->mNumberBuffers = 1;
    mOutputBufferList->mBuffers[0].mNumberChannels = outputASBD->mChannelsPerFrame;
    mOutputBufferList->mBuffers[0].mDataByteSize = mOutputBufferSize;
    mOutputBufferList->mBuffers[0].mData = mOutputBuffer;
    
    err = [mMyAudioConverter convert:&numPackets :mPacketDescriptions :self];
    if (err) goto bail;
    
    numFrames = numPackets * outputASBD->mFramesPerPacket;
 
    // we have completed the conversion when AudioConverterFillComplexBuffer returns zero packets
    mConversionComplete = (numPackets == 0);
 
    // write it to the movie file
    if (numPackets > 0) {
    
        // if the format requires packet descriptions, we need to add them one at a time
        // packet descriptions describe the packet layout of a buffer of data where the size of
        // each packet may not be the same or where there is extraneous data between packets
        if (mPacketDescriptions) {
        
            for (i = 0; i < numPackets; i++) {
                err = AddMediaSample2(mSoundMedia,                                                                                                                      // the Media
                                      mOutputBufferList->mBuffers[0].mData + mPacketDescriptions[i].mStartOffset,                                                       // const UInt8 * dataIn
                                      mPacketDescriptions[i].mDataByteSize,                                                                                             // ByteCount size
                                      (mPacketDescriptions[i].mVariableFramesInPacket ? mPacketDescriptions[i].mVariableFramesInPacket : outputASBD->mFramesPerPacket), // TimeValue64 decodeDurationPerSample
                                      0,                                                                                                                                // TimeValue64 displayOffset
                                      (SampleDescriptionHandle)mSoundDescription,                                                                                       // SampleDescriptionHandle sampleDescriptionH
                                      1,                                                                                                                                // ItemCount numberOfSamples
                                      0,                                                                                                                                // MediaSampleFlags sampleFlags
                                      NULL);                                                                                                                            // TimeValue64 * sampleDecodeTimeOut
                if (err) goto bail;
            }
        } else {
            // numSamples should be the same as numFrames calculated above
            UInt32 numSamples = (mOutputBufferList->mBuffers[0].mDataByteSize / outputASBD->mBytesPerPacket) * outputASBD->mFramesPerPacket;
            
            // make believe the frames in each packet are individually accessible (decodeDurationPerSample == 1)
            // this is commonly known as "THE LIE" and while it is the truth for PCM it is a lie for all CBR compressed formats
            err = AddMediaSample2(mSoundMedia,                                  // the Media
                                  mOutputBufferList->mBuffers[0].mData,         // const UInt8 * dataIn
                                  mOutputBufferList->mBuffers[0].mDataByteSize, // ByteCount size
                                  1,                                            // TimeValue64 decodeDurationPerSample
                                  0,                                            // TimeValue64 displayOffset
                                  (SampleDescriptionHandle)mSoundDescription,   // SampleDescriptionHandle sampleDescriptionH
                                  numSamples,                                   // ItemCount numberOfSamples
                                  0,                                            // MediaSampleFlags sampleFlags
                                  NULL);                                        // TimeValue64 * sampleDecodeTimeOut
            if (err) goto bail;
        }
        
        mLocationInFile += numPackets;
    }
        
bail:
    
    if (err) numFrames = 0;
    
    *ioNumFrames = numFrames;
    
    return err;
}
 
// this method prepare the specified movie for extraction by opening an extraction session, configuring
// and setting the output ASBD and the output layout if one exists - it also sets the start time to 0
// and calculates the total number of samples to export
- (OSStatus) configureExtractionSessionWithMovie:(Movie)inMovie
{
    OSStatus err;
    
    // open a movie audio extraction session
    err = MovieAudioExtractionBegin(inMovie, 0, &mAudioExtractionSession);
    if (err) goto bail;
 
    // set the extraction ASBD
    err = MovieAudioExtractionSetProperty(mAudioExtractionSession,
                                          kQTPropertyClass_MovieAudioExtraction_Audio,
                                          kQTMovieAudioExtractionAudioPropertyID_AudioStreamBasicDescription,
                                          sizeof(AudioStreamBasicDescription),
                                          [mMyAudioConverter inputFormat]);
    if (err) goto bail;
    
    // set the extraction channel layout
    err = MovieAudioExtractionSetProperty(mAudioExtractionSession,
                                          kQTPropertyClass_MovieAudioExtraction_Audio,
                                          kQTMovieAudioExtractionAudioPropertyID_AudioChannelLayout,
                                          [mMyAudioConverter channelLayoutSize],
                                          [mMyAudioConverter channelLayout]);
    if (err) goto bail;
    
    // set the chosen render quality - this is the same quality value set on the Audio Converter
    err = MovieAudioExtractionSetProperty(mAudioExtractionSession,
                                          kQTPropertyClass_MovieAudioExtraction_Audio,
                                          kQTMovieAudioExtractionAudioPropertyID_RenderQuality,
                                          sizeof(UInt32), [mMyAudioConverter renderQuality]);
    if (err) goto bail;
 
    // set the extraction start time - we always start at zero, but you don't have to
    // this is the default but we set it anyway for completeness
    TimeRecord startTime = { 0, 0, GetMovieTimeScale(inMovie), GetMovieTimeBase(inMovie) };
    
    err = MovieAudioExtractionSetProperty(mAudioExtractionSession,
                                          kQTPropertyClass_MovieAudioExtraction_Movie,
                                          kQTMovieAudioExtractionMoviePropertyID_CurrentTime,
                                          sizeof(TimeRecord), &startTime);
    if (err) goto bail;
 
bail:
        
    return err;
}
 
// create and configure the output file
- (OSStatus)createOutputFile:(AudioStreamBasicDescription *)inOutputASBD
{
    Handle outputMovieDataRef;
    OSType outputMovieDataRefType;
    CFStringRef outputMovieFullPathString;
    
    OSStatus err;
 
    err = QTNewDataReferenceFromFSRefCFString(&mParentRef, (CFStringRef)mFileName, 0, &outputMovieDataRef, &outputMovieDataRefType);
    if (err) goto bail;
 
    // create a new movie file. 
    // If you're using CreateMovieFile, consider switching to CreateMovieStorage, which is long-file-name aware and besides, FSSpecs are dead
    err = CreateMovieStorage(outputMovieDataRef, outputMovieDataRefType, 'TVOD', 0, createMovieFileDeleteCurFile, &mOutputMovieStorageDH, &mOutputMovie);
    if (err) goto bail;
 
    // remember a URL for the movie file so we can open it in QuickTime Player after export is complete
    err = QTGetDataReferenceFullPathCFString(outputMovieDataRef, outputMovieDataRefType, kQTPOSIXPathStyle, &outputMovieFullPathString);
    if (err) goto bail;    
    
    mOutputMovieFileURL = CFURLCreateWithFileSystemPath(kCFAllocatorDefault, outputMovieFullPathString, kCFURLPOSIXPathStyle, false);
 
    err = QTSoundDescriptionCreate([mMyAudioConverter outputFormat],
                                   [mMyAudioConverter channelLayout], [mMyAudioConverter channelLayoutSize],
                                   [mMyAudioConverter magicCookie], [mMyAudioConverter magicCookieSize],
                                   kQTSoundDescriptionKind_Movie_LowestPossibleVersion, &mSoundDescription);
    if (err) goto bail;
 
    // create the sound track
    Track track = NewMovieTrack(mOutputMovie, 0, 0, kFullVolume);
    if (err = GetMoviesError()) goto bail;
 
    mSoundMedia = NewTrackMedia(track, SoundMediaType, (TimeScale)inOutputASBD->mSampleRate, NULL, 0);
    if (err = GetMoviesError()) goto bail;
 
    err = BeginMediaEdits(mSoundMedia);
 
bail:
 
    if (outputMovieDataRef) DisposeHandle(outputMovieDataRef);
    if (outputMovieFullPathString) CFRelease(outputMovieFullPathString);
 
    return err;
}
 
// calculate the duration of the longest audio track in the movie
// if the audio tracks end at time N and the movie is much 
// longer we don't want to keep converting - the Movie Audio Extration
// (the API we're using to provide source) will happily
// return zeroes until it reaches the movie duration
- (void)setMovieConversionDuration
{
    TimeValue maxDuration = 0;
    UInt8 i;
 
    SInt32 trackCount = GetMovieTrackCount([mQTMovie quickTimeMovie]);
    
    if (trackCount) {
        for (i = 1; i < trackCount + 1; i++) {
            Track aTrack = GetMovieIndTrackType([mQTMovie quickTimeMovie],
                                                i,
                                                SoundMediaType,
                                                movieTrackMediaType);
            if (aTrack) {
                TimeValue aDuration = GetTrackDuration(aTrack);
            
                if (aDuration > maxDuration) maxDuration = aDuration;
            }
        }
        
        mMovieDuration = (Float64)maxDuration / (Float64)GetMovieTimeScale([mQTMovie quickTimeMovie]);
    }
}
 
// this completion method gets called at the end of the extraction session or may be called
// earlier if an error has occured - its main purpose is to clean up the world so a MovieWriter
// instance can be used over and over again
//
// in this particular case if we completed successfully we launch QTPlayer with the .mov file
// and if an error occurs we pass it back to the client though the progress info object
- (void) exportCompletedNotification:(NSError *)inError
{
    if (noErr == [inError code]) {
        
        NSWorkspace *ws = [NSWorkspace sharedWorkspace];
        
        [ws openFile:[(NSURL *)mOutputMovieFileURL path] withApplication:@"QuickTime Player"];
    }
    
    if (mFileName) {
        [mFileName release];
        mFileName = nil;
    }
    
    if (mOutputMovieFileURL) {
        CFRelease(mOutputMovieFileURL);
        mOutputMovieFileURL = NULL;
    }
    
    if (mAudioExtractionSession){
        MovieAudioExtractionEnd(mAudioExtractionSession);
        mAudioExtractionSession = NULL;
    }
    
    if (mMyAudioConverter) {
        [mMyAudioConverter release];
        mMyAudioConverter = nil;
    }
    
    if (mQTMovie) {
        [mQTMovie release];
        mQTMovie = nil;
    }
    
    mMovieDuration = 0;
    
    if (mCloneMovie) {
        DisposeMovie(mCloneMovie);
        mCloneMovie = NULL;
    }
    
    mExtractionComplete = NO;
    mConversionComplete = NO;
    mIsConverting = NO;
    
    mLocationInFile = 0;
    mOutputFramesCompleted = 0;
    mTotalNumberOfOutputFrames = 0;
    mOneSegmentOfOutputFrames = 0;
    
    if (mOutputMovieStorageDH) {
        CloseComponent(mOutputMovieStorageDH);
        mOutputMovieStorageDH = 0;
    }
    
    mSoundMedia = 0;
    
    if (mSoundDescription) {
        DisposeHandle((Handle)mSoundDescription);
        mSoundDescription = NULL;
    }
    
    if (mExtractionBuffList) {
        free(mExtractionBuffList);
        mExtractionBuffList = NULL;
    }
    
    if (mExtractionBuffer) {
        free(mExtractionBuffer);
        mExtractionBuffer = NULL;
        mExtractionBufferSize = 0;
    }
    
    if (mOutputBufferList) {
        free(mOutputBufferList);
        mOutputBufferList = NULL;
    }
    
    if (mOutputBuffer) {
        free(mOutputBuffer);
        mOutputBuffer = NULL;
        mOutputBufferSize = 0;
    }
    
    if (mPacketDescriptions) {
        free(mPacketDescriptions);
        mPacketDescriptions = NULL;
    }
    
    [mLock unlock];
 
    // if the client implemented a progress proc. call it now
    if (TRUE == mDelegateShouldContinueOp) {
        
        [mProgressInfo setPhase:MovieWriterExportEnd];
        [mProgressInfo setProgressValue:nil];
        [mProgressInfo setExportStatus:((noErr != [inError code]) && (userCanceledErr != [inError code]) ? inError : nil)];
        
        [[self delegate] shouldContinueOperationWithProgressInfo:mProgressInfo];
    }
}
 
- (MovieAudioExtractionRef)audioExtractionSession;
{
    return mAudioExtractionSession;
}
 
- (AudioBufferList *)extractionBufferList
{
    return mExtractionBuffList;
}
 
- (UInt32)extractionBytesPerFrame
{
    AudioStreamBasicDescription *extractionASBD = [mMyAudioConverter inputFormat];
 
    return extractionASBD->mBytesPerFrame;
}
 
- (BOOL)extractionComplete
{
    return mExtractionComplete;
}
 
- (void)setExtractionComplete:(BOOL)flag
{
    mExtractionComplete = flag;
}
 
#pragma mark ---- delegate ----
 
// methods to support setting up a delegate of this class
- (id)delegate
{
    return mDelegate;
}
 
- (void)setDelegate:(id)inDelegate
{
    mDelegate = inDelegate;
    
    mDelegateShouldContinueOp = [mDelegate respondsToSelector:@selector(shouldContinueOperationWithProgressInfo:)];
}
 
@end


Copyright © 2006 Apple Computer, Inc. All Rights Reserved. Terms of Use | Privacy Policy | Updated: 2006-11-08