iphone游戏的声音处理－流播放文件

流播放文件即用AudioStream 和 AudioQueue 来播放文件。好处是可以快速的开始播放，减少读文件的过程，适合大文件特别是背景音乐的播放。坏处是一次只能播放一个文件，如果要换播放文件，中间需要一定的时间。但是因为iPhone的文件读取时间只有10秒，对于资源较大的文件，只能考虑这个方式了。下面我将分享一下我在这方面的一点经验：1. 单个文件播放2. 在线文件播放

 

1. 单个文件播放

BOOL isPlaying; /*-------------------USED FOR LOCAL FILE--------------------*/ AudioFileID audioFile; AudioStreamBasicDescription dataFormat; AudioStreamPacketDescription *packetDescs; UInt64 packetIndex; UInt32 numPacketsToRead; BOOL repeat; BOOL trackClosed; /*--------------------USED FOR PUBLIC------------------------*/ BOOL trackEnded; AudioQueueRef queue; AudioQueueBufferRef buffers[NUM_QUEUE_BUFFERS];

以上是需要定义的为单独文件播放的所需要的元素。可以定义在类里面。

2. 在线文件播放

NSURL *url; AudioFileStreamID audioFileStream; // the audio file stream parser AudioStreamPacketDescription packetDescsQueue[kAQMaxPacketDescs]; // packet descriptions for enqueuing audio CFReadStreamRef stream; unsigned int fillBufferIndex; // the index of the audioQueueBuffer that is being filled size_t bytesFilled; // how many bytes have been filled size_t packetsFilled; // how many packets have been filled bool inuse[kNumAQBufs]; // flags to indicate that a buffer is still in use bool started; // flag to indicate that the queue has been started bool failed; // flag to indicate an error occurred bool discontinuous; // flag to trigger bug-avoidance pthread_mutex_t mutex; // a mutex to protect the inuse flags pthread_cond_t cond; // a condition varable for handling the inuse flags pthread_mutex_t mutex2; // a mutex to protect the AudioQueue buffer BOOL trackEnded; AudioQueueRef queue; AudioQueueBufferRef buffers[NUM_QUEUE_BUFFERS];

利用http1.1协议播放在线文件。以上是在线文件播放所需要的参数。

#define NUM_QUEUE_BUFFERS 3 #define kNumAQBufs 6 // number of audio queue buffers we allocate #define kAQBufSize 32 * 1024 // number of bytes in each audio queue buffer #define kAQMaxPacketDescs 512 // number of packet descriptions in our array

 

这里是定义的一些参数，NUM_QUEUE_BUFFERS 用于播放本地文件，而 kNumAQBufs 用于播放在线文件。


3. 本地文件初始化
- (id)initWithPath:(NSString*)path { UInt32 size, maxPacketSize; char *cookie; int i; if (kxxxTrackActive) { NSLog(@"Other music is playing."); return nil; } if (path == nil) return nil; if(!(self = [super init])) return nil; // try to open up the file using the specified path if (noErr != AudioFileOpenURL((CFURLRef)[NSURL fileURLWithPath:path], 0x01, 0, &audioFile)) { NSLog(@"File can not be opened!"); return nil; } // get the data format of the file size = sizeof(dataFormat); AudioFileGetProperty(audioFile, kAudioFilePropertyDataFormat, &size, &dataFormat); // create a new playback queue using the specified data format and buffer callback AudioQueueNewOutput(&dataFormat, BufferCallback, self, nil, nil, 0, &queue); // calculate number of packets to read and allocate space for packet descriptions if needed if (dataFormat.mBytesPerPacket == 0 || dataFormat.mFramesPerPacket == 0) { // Ask Core Audio to give us a conservative estimate of the largest packet size = sizeof(maxPacketSize); AudioFileGetProperty(audioFile, kAudioFilePropertyPacketSizeUpperBound, &size, &maxPacketSize); if (maxPacketSize > kxxxBufferSizeBytes) { /*Limitation for the maximum buffer size*/ maxPacketSize = kxxxBufferSizeBytes; NSLog(@"Size out of bounds!"); } // calculate how many packs to read numPacketsToRead = kxxxBufferSizeBytes / maxPacketSize; // will need a packet description for each packet to allocate space accordingly packetDescs = malloc(sizeof(AudioStreamPacketDescription) * numPacketsToRead); } else { // constant bitrate numPacketsToRead = kxxxBufferSizeBytes / dataFormat.mBytesPerPacket; // don't need packet descriptions for CBR data packetDescs = nil; } // see if file uses a magic cookie (a magic cookie is meta data which some formats use) AudioFileGetPropertyInfo(audioFile, kAudioFilePropertyMagicCookieData, &size, nil); if (size > 0) { // copy the cookie data from the file into the audio queue cookie = malloc(sizeof(char) * size); AudioFileGetProperty(audioFile, kAudioFilePropertyMagicCookieData, &size, cookie); AudioQueueSetProperty(queue, kAudioQueueProperty_MagicCookie, cookie, size); free(cookie); } // we want to know when the playing state changes so we can properly dispose of the audio queue when it's done AudioQueueAddPropertyListener(queue, kAudioQueueProperty_IsRunning, propertyListenerCallback, self); // allocate and prime buffers with some data packetIndex = 0; for (i = 0; i < NUM_QUEUE_BUFFERS; i++) { AudioQueueAllocateBuffer(queue, kxxxBufferSizeBytes, &buffers); if ([self readPacketsIntoBuffer:buffers] == 0) { // this might happen if the file was so short that it needed less buffers than we planned on using break; } } repeat = NO; trackClosed = NO; trackEnded = NO; kxxxTrackActive = YES; return self; }

 

4. 在线文件初始化
- (id)initWithURL:(NSURL*)newUrl { self = [super init]; if (self != nil) { url = [newUrl retain]; } return self; }

算了，废话不多说了，直接上代码，等以后有时间了再逐一解释。

.h文件

#ifdef TARGET_OS_IPHONE #import <UIKit/UIKit.h> #else #import <Cocoa/Cocoa.h> #endif TARGET_OS_IPHONE #import <AudioToolbox/AudioQueue.h> #import <AudioToolbox/AudioFile.h> #include <pthread.h> #include <AudioToolbox/AudioToolbox.h> #define NUM_QUEUE_BUFFERS 3 #define kNumAQBufs 6 // number of audio queue buffers we allocate #define kAQBufSize 32 * 1024 // number of bytes in each audio queue buffer #define kAQMaxPacketDescs 512 // number of packet descriptions in our array @interface xxxxx : NSObject { /*-----------------USED FOR HTTP STREAM------------------*/ NSURL *url; BOOL isPlaying; @public AudioFileStreamID audioFileStream; // the audio file stream parser AudioStreamPacketDescription packetDescsQueue[kAQMaxPacketDescs]; // packet descriptions for enqueuing audio CFReadStreamRef stream; unsigned int fillBufferIndex; // the index of the audioQueueBuffer that is being filled size_t bytesFilled; // how many bytes have been filled size_t packetsFilled; // how many packets have been filled bool inuse[kNumAQBufs]; // flags to indicate that a buffer is still in use bool started; // flag to indicate that the queue has been started bool failed; // flag to indicate an error occurred bool discontinuous; // flag to trigger bug-avoidance pthread_mutex_t mutex; // a mutex to protect the inuse flags pthread_cond_t cond; // a condition varable for handling the inuse flags pthread_mutex_t mutex2; // a mutex to protect the AudioQueue buffer /*-------------------USED FOR LOCAL FILE--------------------*/ AudioFileID audioFile; AudioStreamBasicDescription dataFormat; AudioStreamPacketDescription *packetDescs; UInt64 packetIndex; UInt32 numPacketsToRead; BOOL repeat; BOOL trackClosed; /*--------------------USED FOR PUBLIC------------------------*/ BOOL trackEnded; AudioQueueRef queue; AudioQueueBufferRef buffers[NUM_QUEUE_BUFFERS]; } @property BOOL isPlaying; @property BOOL trackClosed; - (id) initWithURL:(NSURL*) newURL; - (id) initWithPath:(NSString*) path; - (void) setGain:(Float32)gain; - (void) setRepeat:(BOOL)yn; - (void) setPlayingWhenAutoLock; - (void) play; - (void) playURL; - (void) pause; - (void) stopURL; - (void) close; extern NSString *xxxTrackFinishedPlayingNotification; @end

 

 

.m文件

#import "xxxxx.h" #import <CFNetwork/CFNetwork.h> static UInt32 kxxxBufferSizeBytes = 0x10000; // 64k static BOOL kxxxTrackActive = NO; NSString *xxxTrackFinishedPlayingNotification = @"xxxTrackFinishedPlayingNotification"; #pragma mark - #pragma mark CFReadStream Callback Function Prototypes void ReadStreamCallBack(CFReadStreamRef stream, CFStreamEventType eventType, void* dataIn); #pragma mark - #pragma mark Audio Callback Function Prototypes void MyAudioQueueOutputCallback(void* inClientData, AudioQueueRef inAQ, AudioQueueBufferRef inBuffer); void MyAudioQueueIsRunningCallback(void *inUserData, AudioQueueRef inAQ, AudioQueuePropertyID inID); void MyPropertyListenerProc(void *inClientData, AudioFileStreamID inAudioFileStream, AudioFileStreamPropertyID inPropertyID, UInt32 *ioFlags); void MyPacketsProc(void *inClientData, UInt32 inNumberBytes, UInt32 inNumberPackets, const void *inInputData, AudioStreamPacketDescription *inPacketDescriptions); OSStatus MyEnqueueBuffer(xxxxx* myData); #ifdef TARGET_OS_IPHONE void MyAudioSessionInterruptionListener(void *inClientData, UInt32 inInterruptionState); #endif #pragma mark - #pragma mark Audio Callback Function Implementations // // MyPropertyListenerProc // // Receives notification when the AudioFileStream has audio packets to be // played. In response, this function creates the AudioQueue, getting it // ready to begin playback (playback won't begin until audio packets are // sent to the queue in MyEnqueueBuffer). // // This function is adapted from Apple's example in AudioFileStreamExample with // kAudioQueueProperty_IsRunning listening added. // void MyPropertyListenerProc(void *inClientData, AudioFileStreamID inAudioFileStream, AudioFileStreamPropertyID inPropertyID, UInt32 *ioFlags) { // this is called by audio file stream when it finds property values xxxxx* myData = (xxxxx*)inClientData; OSStatus err = noErr; switch (inPropertyID) { case kAudioFileStreamProperty_ReadyToProducePackets : { myData->discontinuous = true; // the file stream parser is now ready to produce audio packets. // get the stream format. AudioStreamBasicDescription asbd; UInt32 asbdSize = sizeof(asbd); err = AudioFileStreamGetProperty(inAudioFileStream, kAudioFileStreamProperty_DataFormat, &asbdSize, &asbd); if (err) { NSLog(@"get kAudioFileStreamProperty_DataFormat"); myData->failed = true; break; } // create the audio queue err = AudioQueueNewOutput(&asbd, MyAudioQueueOutputCallback, myData, NULL, NULL, 0, &myData->queue); if (err) { NSLog(@"AudioQueueNewOutput"); myData->failed = true; break; } // listen to the "isRunning" property err = AudioQueueAddPropertyListener(myData->queue, kAudioQueueProperty_IsRunning, MyAudioQueueIsRunningCallback, myData); if (err) { NSLog(@"AudioQueueAddPropertyListener"); myData->failed = true; break; } // allocate audio queue buffers for (unsigned int i = 0; i < kNumAQBufs; ++i) { err = AudioQueueAllocateBuffer(myData->queue, kAQBufSize, &myData->buffers); if (err) { NSLog(@"AudioQueueAllocateBuffer"); myData->failed = true; break; } } // get the cookie size UInt32 cookieSize; Boolean writable; err = AudioFileStreamGetPropertyInfo(inAudioFileStream, kAudioFileStreamProperty_MagicCookieData, &cookieSize, &writable); if (err) { NSLog(@"info kAudioFileStreamProperty_MagicCookieData"); break; } // get the cookie data void* cookieData = calloc(1, cookieSize); err = AudioFileStreamGetProperty(inAudioFileStream, kAudioFileStreamProperty_MagicCookieData, &cookieSize, cookieData); if (err) { NSLog(@"get kAudioFileStreamProperty_MagicCookieData"); free(cookieData); break; } // set the cookie on the queue. err = AudioQueueSetProperty(myData->queue, kAudioQueueProperty_MagicCookie, cookieData, cookieSize); free(cookieData); if (err) { NSLog(@"set kAudioQueueProperty_MagicCookie"); break; } break; } } } // // MyPacketsProc // // When the AudioStream has packets to be played, this function gets an // idle audio buffer and copies the audio packets into it. The calls to // MyEnqueueBuffer won't return until there are buffers available (or the // playback has been stopped). // // This function is adapted from Apple's example in AudioFileStreamExample with // CBR functionality added. // void MyPacketsProc(void *inClientData, UInt32 inNumberBytes, UInt32 inNumberPackets, const void *inInputData, AudioStreamPacketDescription *inPacketDescriptions) { // this is called by audio file stream when it finds packets of audio xxxxx* myData = (xxxxx*)inClientData; // we have successfully read the first packests from the audio stream, so // clear the "discontinuous" flag myData->discontinuous = false; // the following code assumes we're streaming VBR data. for CBR data, the second branch is used. if (inPacketDescriptions) { for (int i = 0; i < inNumberPackets; ++i) { SInt64 packetOffset = inPacketDescriptions.mStartOffset; SInt64 packetSize = inPacketDescriptions.mDataByteSize; // If the audio was terminated before this point, then // exit. if (myData->trackEnded) { return; } // if the space remaining in the buffer is not enough for this packet, then enqueue the buffer. size_t bufSpaceRemaining = kAQBufSize - myData->bytesFilled; if (bufSpaceRemaining < packetSize) { MyEnqueueBuffer(myData); } pthread_mutex_lock(&myData->mutex2); // If the audio was terminated while waiting for a buffer, then // exit. if (myData->trackEnded) { pthread_mutex_unlock(&myData->mutex2); return; } // copy data to the audio queue buffer AudioQueueBufferRef fillBuf = myData->buffers[myData->fillBufferIndex]; memcpy((char*)fillBuf->mAudioData + myData->bytesFilled, (const char*)inInputData + packetOffset, packetSize); pthread_mutex_unlock(&myData->mutex2); // fill out packet description myData->packetDescsQueue[myData->packetsFilled] = inPacketDescriptions; myData->packetDescsQueue[myData->packetsFilled].mStartOffset = myData->bytesFilled; // keep track of bytes filled and packets filled myData->bytesFilled += packetSize; myData->packetsFilled += 1; // if that was the last free packet description, then enqueue the buffer. size_t packetsDescsRemaining = kAQMaxPacketDescs - myData->packetsFilled; if (packetsDescsRemaining == 0) { MyEnqueueBuffer(myData); } } } else { size_t offset = 0; while (inNumberBytes) { // if the space remaining in the buffer is not enough for this packet, then enqueue the buffer. size_t bufSpaceRemaining = kAQBufSize - myData->bytesFilled; if (bufSpaceRemaining < inNumberBytes) { MyEnqueueBuffer(myData); } pthread_mutex_lock(&myData->mutex2); // If the audio was terminated while waiting for a buffer, then // exit. if (myData->trackEnded) { pthread_mutex_unlock(&myData->mutex2); return; } // copy data to the audio queue buffer AudioQueueBufferRef fillBuf = myData->buffers[myData->fillBufferIndex]; bufSpaceRemaining = kAQBufSize - myData->bytesFilled; size_t copySize; if (bufSpaceRemaining < inNumberBytes) { copySize = bufSpaceRemaining; } else { copySize = inNumberBytes; } memcpy((char*)fillBuf->mAudioData + myData->bytesFilled, (const char*)(inInputData + offset), copySize); pthread_mutex_unlock(&myData->mutex2); // keep track of bytes filled and packets filled myData->bytesFilled += copySize; myData->packetsFilled = 0; inNumberBytes -= copySize; offset += copySize; } } } // // MyEnqueueBuffer // // Called from MyPacketsProc and connectionDidFinishLoading to pass filled audio // bufffers (filled by MyPacketsProc) to the AudioQueue for playback. This // function does not return until a buffer is idle for further filling or // the AudioQueue is stopped. // // This function is adapted from Apple's example in AudioFileStreamExample with // CBR functionality added. // OSStatus MyEnqueueBuffer(xxxxx* myData) { OSStatus err = noErr; myData->inuse[myData->fillBufferIndex] = true; // set in use flag // enqueue buffer AudioQueueBufferRef fillBuf = myData->buffers[myData->fillBufferIndex]; fillBuf->mAudioDataByteSize = myData->bytesFilled; if (myData->packetsFilled) { err = AudioQueueEnqueueBuffer(myData->queue, fillBuf, myData->packetsFilled, myData->packetDescsQueue); } else { err = AudioQueueEnqueueBuffer(myData->queue, fillBuf, 0, NULL); } if (err) { NSLog(@"AudioQueueEnqueueBuffer"); myData->failed = true; return err; } if (!myData->started) { // start the queue if it has not been started already err = AudioQueueStart(myData->queue, NULL); if (err) { NSLog(@"AudioQueueStart"); myData->failed = true; return err; } myData->started = true; } // go to next buffer if (++myData->fillBufferIndex >= kNumAQBufs) myData->fillBufferIndex = 0; myData->bytesFilled = 0; // reset bytes filled myData->packetsFilled = 0; // reset packets filled // wait until next buffer is not in use pthread_mutex_lock(&myData->mutex); while (myData->inuse[myData->fillBufferIndex] && !myData->trackEnded) { pthread_cond_wait(&myData->cond, &myData->mutex); } pthread_mutex_unlock(&myData->mutex); return err; } // // MyFindQueueBuffer // // Returns the index of the specified buffer in the audioQueueBuffer array. // // This function is unchanged from Apple's example in AudioFileStreamExample. // int MyFindQueueBuffer(xxxxx* myData, AudioQueueBufferRef inBuffer) { for (unsigned int i = 0; i < kNumAQBufs; ++i) { if (inBuffer == myData->buffers) return i; } return -1; } // // MyAudioQueueOutputCallback // // Called from the AudioQueue when playback of specific buffers completes. This // function signals from the AudioQueue thread to the AudioStream thread that // the buffer is idle and available for copying data. // // This function is unchanged from Apple's example in AudioFileStreamExample. // void MyAudioQueueOutputCallback(void* inClientData, AudioQueueRef inAQ, AudioQueueBufferRef inBuffer) { // this is called by the audio queue when it has finished decoding our data. // The buffer is now free to be reused. xxxxx* myData = (xxxxx*)inClientData; unsigned int bufIndex = MyFindQueueBuffer(myData, inBuffer); // signal waiting thread that the buffer is free. pthread_mutex_lock(&myData->mutex); myData->inuse[bufIndex] = false; pthread_cond_signal(&myData->cond); pthread_mutex_unlock(&myData->mutex); } // // MyAudioQueueIsRunningCallback // // Called from the AudioQueue when playback is started or stopped. This // information is used to toggle the observable "isPlaying" property and // set the "finished" flag. // void MyAudioQueueIsRunningCallback(void *inUserData, AudioQueueRef inAQ, AudioQueuePropertyID inID) { xxxxx *myData = (xxxxx *)inUserData; NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; if (myData.isPlaying) { myData->trackEnded = true; myData.isPlaying = false; #ifdef TARGET_OS_IPHONE AudioSessionSetActive(false); #endif } else { myData.isPlaying = true; if (myData->trackEnded) { myData.isPlaying = false; } // // Note about this bug avoidance quirk: // // On cleanup of the AudioQueue thread, on rare occasions, there would // be a crash in CFSetContainsValue as a CFRunLoopObserver was getting // removed from the CFRunLoop. // // After lots of testing, it appeared that the audio thread was // attempting to remove CFRunLoop observers from the CFRunLoop after the // thread had already deallocated the run loop. // // By creating an NSRunLoop for the AudioQueue thread, it changes the // thread destruction order and seems to avoid this crash bug -- or // at least I haven't had it since (nasty hard to reproduce error!) // [NSRunLoop currentRunLoop]; } [pool release]; } #ifdef TARGET_OS_IPHONE // // MyAudioSessionInterruptionListener // // Invoked if the audio session is interrupted (like when the phone rings) // void MyAudioSessionInterruptionListener(void *inClientData, UInt32 inInterruptionState) { } #endif #pragma mark - #pragma mark CFReadStream Callback Function Implementations // // ReadStreamCallBack // // This is the callback for the CFReadStream from the network connection. This // is where all network data is passed to the AudioFileStream. // // Invoked when an error occurs, the stream ends or we have data to read. // void ReadStreamCallBack(CFReadStreamRef stream, CFStreamEventType eventType, void* dataIn) { xxxxx *myData = (xxxxx *)dataIn; if (eventType == kCFStreamEventErrorOccurred) { myData->failed = YES; } else if (eventType == kCFStreamEventEndEncountered) { if (myData->failed || myData->trackEnded) { return; } // // If there is a partially filled buffer, pass it to the AudioQueue for // processing // if (myData->bytesFilled) { MyEnqueueBuffer(myData); } // // If the AudioQueue started, then flush it (to make certain everything // sent thus far will be processed) and subsequently stop the queue. // if (myData->started) { OSStatus err = AudioQueueFlush(myData->queue); if (err) { NSLog(@"AudioQueueFlush"); return; } err = AudioQueueStop(myData->queue, false); if (err) { NSLog(@"AudioQueueStop"); return; } CFReadStreamClose(stream); CFRelease(stream); myData->stream = nil; } else { // // If we have reached the end of the file without starting, then we // have failed to find any audio in the file. Abort. // myData->failed = YES; } } else if (eventType == kCFStreamEventHasBytesAvailable) { if (myData->failed || myData->trackEnded) { return; } // // Read the bytes from the stream // UInt8 bytes[kAQBufSize]; CFIndex length = CFReadStreamRead(stream, bytes, kAQBufSize); if (length == -1) { myData->failed = YES; return; } // // Parse the bytes read by sending them through the AudioFileStream // if (length > 0) { if (myData->discontinuous) { OSStatus err = AudioFileStreamParseBytes(myData->audioFileStream, length, bytes, kAudioFileStreamParseFlag_Discontinuity); if (err) { NSLog(@"AudioFileStreamParseBytes"); myData->failed = true;} } else { OSStatus err = AudioFileStreamParseBytes(myData->audioFileStream, length, bytes, 0); if (err) { NSLog(@"AudioFileStreamParseBytes"); myData->failed = true; } } } } } @interface xxxxx (private) static void propertyListenerCallback(void *inUserData, AudioQueueRef queueObject, AudioQueuePropertyID propertyID); - (void) playBackIsRunningStateChanged; static void BufferCallback(void *inUserData, AudioQueueRef inAQ, AudioQueueBufferRef buffer); - (void) callbackForBuffer:(AudioQueueBufferRef)buffer; - (UInt32) readPacketsIntoBuffer:(AudioQueueBufferRef)buffer; @end @implementation xxxxx @synthesize isPlaying, trackClosed; #pragma mark - #pragma mark xxxxx - (void)dealloc { [self close]; if (packetDescs != nil) free(packetDescs); [url release]; [super dealloc]; } - (void)close { // it is preferrable to call close first, if there is a problem waiting for an autorelease if (trackClosed) return; trackClosed = YES; AudioQueueStop(queue, YES); // <-- YES means stop immediately AudioQueueDispose(queue, YES); AudioFileClose(audioFile); kxxxTrackActive = NO; } - (id)initWithURL:(NSURL*)newUrl { self = [super init]; if (self != nil) { url = [newUrl retain]; } return self; } - (id)initWithPath:(NSString*)path { UInt32 size, maxPacketSize; char *cookie; int i; if (kxxxTrackActive) { NSLog(@"Other music is playing."); return nil; } if (path == nil) return nil; if(!(self = [super init])) return nil; // try to open up the file using the specified path if (noErr != AudioFileOpenURL((CFURLRef)[NSURL fileURLWithPath:path], 0x01, 0, &audioFile)) { NSLog(@"File can not be opened!"); return nil; } // get the data format of the file size = sizeof(dataFormat); AudioFileGetProperty(audioFile, kAudioFilePropertyDataFormat, &size, &dataFormat); // create a new playback queue using the specified data format and buffer callback AudioQueueNewOutput(&dataFormat, BufferCallback, self, nil, nil, 0, &queue); // calculate number of packets to read and allocate space for packet descriptions if needed if (dataFormat.mBytesPerPacket == 0 || dataFormat.mFramesPerPacket == 0) { // Ask Core Audio to give us a conservative estimate of the largest packet size = sizeof(maxPacketSize); AudioFileGetProperty(audioFile, kAudioFilePropertyPacketSizeUpperBound, &size, &maxPacketSize); if (maxPacketSize > kxxxBufferSizeBytes) { /*Limitation for the maximum buffer size*/ maxPacketSize = kxxxBufferSizeBytes; NSLog(@"Size out of bounds!"); } // calculate how many packs to read numPacketsToRead = kxxxBufferSizeBytes / maxPacketSize; // will need a packet description for each packet to allocate space accordingly packetDescs = malloc(sizeof(AudioStreamPacketDescription) * numPacketsToRead); } else { // constant bitrate numPacketsToRead = kxxxBufferSizeBytes / dataFormat.mBytesPerPacket; // don't need packet descriptions for CBR data packetDescs = nil; } // see if file uses a magic cookie (a magic cookie is meta data which some formats use) AudioFileGetPropertyInfo(audioFile, kAudioFilePropertyMagicCookieData, &size, nil); if (size > 0) { // copy the cookie data from the file into the audio queue cookie = malloc(sizeof(char) * size); AudioFileGetProperty(audioFile, kAudioFilePropertyMagicCookieData, &size, cookie); AudioQueueSetProperty(queue, kAudioQueueProperty_MagicCookie, cookie, size); free(cookie); } // we want to know when the playing state changes so we can properly dispose of the audio queue when it's done AudioQueueAddPropertyListener(queue, kAudioQueueProperty_IsRunning, propertyListenerCallback, self); // allocate and prime buffers with some data packetIndex = 0; for (i = 0; i < NUM_QUEUE_BUFFERS; i++) { AudioQueueAllocateBuffer(queue, kxxxBufferSizeBytes, &buffers); if ([self readPacketsIntoBuffer:buffers] == 0) { // this might happen if the file was so short that it needed less buffers than we planned on using break; } } repeat = NO; trackClosed = NO; trackEnded = NO; kxxxTrackActive = YES; return self; } - (void) setGain:(Float32) gain { if (trackClosed) return; AudioQueueSetParameter(queue, kAudioQueueParam_Volume, gain); } - (void) setRepeat:(BOOL) yn { repeat = yn; } - (void) play { if (trackClosed) return; OSStatus result = AudioQueuePrime(queue, 1, nil); if (result) { NSLog(@"play: error priming AudioQueue"); return; } AudioQueueStart(queue, nil); } - (void) playURL{ [NSThread detachNewThreadSelector:@selector(startPlay) toTarget:self withObject:nil]; } - (void) stopURL { if (stream) { CFReadStreamClose(stream); CFRelease(stream); stream = nil; if (trackEnded) { return; } if (started) { // // Set finished to true *before* we call stop. This is to handle our // third thread... // - This method is called from main (UI) thread // - The AudioQueue thread (which owns the AudioQueue buffers nad // will delete them as soon as we call AudioQueueStop) // - URL connection thread is copying data from AudioStream to // AudioQueue buffer // We set this flag to tell the URL connection thread to stop // copying. // pthread_mutex_lock(&mutex2); trackEnded = true; OSStatus err = AudioQueueStop(queue, true); if (err) { NSLog(@"AudioQueueStop"); } pthread_mutex_unlock(&mutex2); pthread_mutex_lock(&mutex); pthread_cond_signal(&cond); pthread_mutex_unlock(&mutex); } else { trackEnded = true; self.isPlaying = YES; self.isPlaying = NO; } } } - (void) setPlayingWhenAutoLock { #ifdef TARGET_OS_IPHONE // Set the audio session category so that we continue to play if the iPhone/iPod auto-locks. AudioSessionInitialize (NULL, // 'NULL' to use the default (main) run loop NULL, // 'NULL' to use the default run loop mode MyAudioSessionInterruptionListener, // a reference to your interruption callback self // data to pass to your interruption listener callback ); UInt32 sessionCategory = kAudioSessionCategory_MediaPlayback; AudioSessionSetProperty (kAudioSessionProperty_AudioCategory, sizeof (sessionCategory), &sessionCategory); AudioSessionSetActive(true); #endif } - (void) startPlay{ [self retain]; //NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; // // Attempt to guess the file type from the URL. Reading the MIME type // from the CFReadStream would be a better approach since lots of // URL's don't have the right extension. // // If you have a fixed file-type, you may want to hardcode this. // AudioFileTypeID fileTypeHint = kAudioFileMP3Type; NSString *fileExtension = [[url path] pathExtension]; if ([fileExtension isEqual:@"mp3"]) { fileTypeHint = kAudioFileMP3Type; } else if ([fileExtension isEqual:@"wav"]) { fileTypeHint = kAudioFileWAVEType; } else if ([fileExtension isEqual:@"aifc"]) { fileTypeHint = kAudioFileAIFCType; } else if ([fileExtension isEqual:@"aiff"]) { fileTypeHint = kAudioFileAIFFType; } else if ([fileExtension isEqual:@"m4a"]) { fileTypeHint = kAudioFileM4AType; } else if ([fileExtension isEqual:@"mp4"]) { fileTypeHint = kAudioFileMPEG4Type; } else if ([fileExtension isEqual:@"caf"]) { fileTypeHint = kAudioFileCAFType; } else if ([fileExtension isEqual:@"aac"]) { fileTypeHint = kAudioFileAAC_ADTSType; } // initialize a mutex and condition so that we can block on buffers in use. pthread_mutex_init(&mutex, NULL); pthread_cond_init(&cond, NULL); pthread_mutex_init(&mutex2, NULL); // create an audio file stream parser OSStatus err = AudioFileStreamOpen(self, MyPropertyListenerProc, MyPacketsProc, fileTypeHint, &audioFileStream); if (err) { NSLog(@"AudioFileStreamOpen"); goto cleanup; } // // Create the GET request // CFHTTPMessageRef message= CFHTTPMessageCreateRequest(NULL, (CFStringRef)@"GET", (CFURLRef)url, kCFHTTPVersion1_1); stream = CFReadStreamCreateForHTTPRequest(NULL, message); CFRelease(message); if (!CFReadStreamOpen(stream)) { CFRelease(stream); goto cleanup; } // // Set our callback function to receive the data // CFStreamClientContext context = {0, self, NULL, NULL, NULL}; CFReadStreamSetClient(stream, kCFStreamEventHasBytesAvailable | kCFStreamEventErrorOccurred | kCFStreamEventEndEncountered, ReadStreamCallBack, &context); CFReadStreamScheduleWithRunLoop(stream, CFRunLoopGetCurrent(), kCFRunLoopCommonModes); // // Process the run loop until playback is finished or failed. // do { CFRunLoopRunInMode(kCFRunLoopDefaultMode, 0.25, false); if (failed) { [self stopURL]; #ifdef TARGET_OS_IPHONE UIAlertView *alert = [[UIAlertView alloc] initWithTitle:NSLocalizedStringFromTable(@"Audio Error", @"Errors", nil) message:NSLocalizedStringFromTable(@"Attempt to play streaming audio failed.", @"Errors", nil) delegate:self cancelButtonTitle:@"OK" otherButtonTitles: nil]; [alert performSelector:@selector(show) onThread:[NSThread mainThread] withObject:nil waitUntilDone:YES]; [alert release]; #else NSAlert *alert = [NSAlert alertWithMessageText:NSLocalizedString(@"Audio Error", @"") defaultButton:NSLocalizedString(@"OK", @"") alternateButton:nil otherButton:nil informativeTextWithFormat:@"Attempt to play streaming audio failed."]; [alert performSelector:@selector(runModal) onThread:[NSThread mainThread] withObject:nil waitUntilDone:NO]; #endif break; } } while (isPlaying || !trackEnded); cleanup: // // Cleanup the read stream if it is still open // if (stream) { CFReadStreamClose(stream); CFRelease(stream); stream = nil; } // // Close the audio file strea, // err = AudioFileStreamClose(audioFileStream); if (err) { NSLog(@"AudioFileStreamClose"); goto cleanup; } // // Dispose of the Audio Queue // if (started) { err = AudioQueueDispose(queue, true); if (err) { NSLog(@"AudioQueueDispose"); goto cleanup; } } //[pool release]; [self release]; } - (void)pause { if (trackClosed) return; AudioQueuePause(queue); } #pragma mark - #pragma mark Callback static void propertyListenerCallback(void *inUserData, AudioQueueRef queueObject, AudioQueuePropertyID propertyID) { // redirect back to the class to handle it there instead, so we have direct access to the instance variables if (propertyID == kAudioQueueProperty_IsRunning) [(xxxxx*)inUserData playBackIsRunningStateChanged]; } - (void)playBackIsRunningStateChanged { if (trackEnded) { // go ahead and close the track now trackClosed = YES; AudioQueueDispose(queue, YES); AudioFileClose(audioFile); kxxxTrackActive = NO; // we're not in the main thread during this callback, so enqueue a message on the main thread to post notification // that we're done, or else the notification will have to be handled in this thread, making things more difficult [self performSelectorOnMainThread:@selector(postTrackFinishedPlayingNotification:) withObject:nil waitUntilDone:NO]; } } static void BufferCallback(void *inUserData, AudioQueueRef inAQ, AudioQueueBufferRef buffer) { // redirect back to the class to handle it there instead, so we have direct access to the instance variables [(xxxxx*)inUserData callbackForBuffer:buffer]; } - (void) callbackForBuffer:(AudioQueueBufferRef) buffer { // I guess it's possible for the callback to continue to be called since this is in another thread, so to be safe, // don't do anything else if the track is closed, and also don't bother reading anymore packets if the track ended if (trackClosed || trackEnded) return; if ([self readPacketsIntoBuffer:buffer] == 0) { if (repeat) { // End Of File reached, so rewind and refill the buffer using the beginning of the file instead packetIndex = 0; [self readPacketsIntoBuffer:buffer]; } else { // set it to stop, but let it play to the end, where the property listener will pick up that it actually finished AudioQueueStop(queue, NO); trackEnded = YES; } } } - (void) postTrackFinishedPlayingNotification:(id) object { // if we're here then we're in the main thread as specified by the callback, so now we can post notification that // the track is done without the notification observer(s) having to worry about thread safety and autorelease pools [[NSNotificationCenter defaultCenter] postNotificationName:xxxTrackFinishedPlayingNotification object:self]; } - (UInt32)readPacketsIntoBuffer:(AudioQueueBufferRef)buffer { UInt32 numBytes, numPackets; // read packets into buffer from file numPackets = numPacketsToRead; AudioFileReadPackets(audioFile, NO, &numBytes, packetDescs, packetIndex, &numPackets, buffer->mAudioData); if (numPackets > 0) { // - End Of File has not been reached yet since we read some packets, so enqueue the buffer we just read into // the audio queue, to be played next // - (packetDescs ? numPackets : 0) means that if there are packet descriptions (which are used only for Variable // BitRate data (VBR)) we'll have to send one for each packet, otherwise zero buffer->mAudioDataByteSize = numBytes; AudioQueueEnqueueBuffer(queue, buffer, (packetDescs ? numPackets : 0), packetDescs); // move ahead to be ready for next time we need to read from the file packetIndex += numPackets; } return numPackets; } @end

 

代码中对指针形式和数组形式2种各写了不同的代码，大家可以根据个人爱好使用，而且还将url和文件path2种播放方式写在了一起。这个类是xxxxx.h