cocoa iPhone 音频流媒体 demo

// // AudioStreamer.h // StreamingAudioPlayer // // Created by Matt Gallagher on 27/09/08. // Copyright 2008 Matt Gallagher. All rights reserved. // // This software is provided 'as-is', without any express or implied // warranty. In no event will the authors be held liable for any damages // arising from the use of this software. Permission is granted to anyone to // use this software for any purpose, including commercial applications, and to // alter it and redistribute it freely, subject to the following restrictions: // // 1. The origin of this software must not be misrepresented; you must not // claim that you wrote the original software. If you use this software // in a product, an acknowledgment in the product documentation would be // appreciated but is not required. // 2. Altered source versions must be plainly marked as such, and must not be // misrepresented as being the original software. // 3. This notice may not be removed or altered from any source // distribution. // #if TARGET_OS_IPHONE #import <UIKit/UIKit.h> #else #import <Cocoa/Cocoa.h> #endif TARGET_OS_IPHONE #include <pthread.h> #include <AudioToolbox/AudioToolbox.h> #define LOG_QUEUED_BUFFERS 0 #define kNumAQBufs 16 // Number of audio queue buffers we allocate. // Needs to be big enough to keep audio pipeline // busy (non-zero number of queued buffers) but // not so big that audio takes too long to begin // (kNumAQBufs * kAQBufSize of data must be // loaded before playback will start). // // Set LOG_QUEUED_BUFFERS to 1 to log how many // buffers are queued at any time -- if it drops // to zero too often, this value may need to // increase. Min 3, typical 8-24. #define kAQDefaultBufSize 2048 // Number of bytes in each audio queue buffer // Needs to be big enough to hold a packet of // audio from the audio file. If number is too // large, queuing of audio before playback starts // will take too long. // Highly compressed files can use smaller // numbers (512 or less). 2048 should hold all // but the largest packets. A buffer size error // will occur if this number is too small. #define kAQMaxPacketDescs 512 // Number of packet descriptions in our array typedef enum { AS_INITIALIZED = 0, AS_STARTING_FILE_THREAD, AS_WAITING_FOR_DATA, AS_FLUSHING_EOF, AS_WAITING_FOR_QUEUE_TO_START, AS_PLAYING, AS_BUFFERING, AS_STOPPING, AS_STOPPED, AS_PAUSED } AudioStreamerState; typedef enum { AS_NO_STOP = 0, AS_STOPPING_EOF, AS_STOPPING_USER_ACTION, AS_STOPPING_ERROR, AS_STOPPING_TEMPORARILY } AudioStreamerStopReason; typedef enum { AS_NO_ERROR = 0, AS_NETWORK_CONNECTION_FAILED, AS_FILE_STREAM_GET_PROPERTY_FAILED, AS_FILE_STREAM_SEEK_FAILED, AS_FILE_STREAM_PARSE_BYTES_FAILED, AS_FILE_STREAM_OPEN_FAILED, AS_FILE_STREAM_CLOSE_FAILED, AS_AUDIO_DATA_NOT_FOUND, AS_AUDIO_QUEUE_CREATION_FAILED, AS_AUDIO_QUEUE_BUFFER_ALLOCATION_FAILED, AS_AUDIO_QUEUE_ENQUEUE_FAILED, AS_AUDIO_QUEUE_ADD_LISTENER_FAILED, AS_AUDIO_QUEUE_REMOVE_LISTENER_FAILED, AS_AUDIO_QUEUE_START_FAILED, AS_AUDIO_QUEUE_PAUSE_FAILED, AS_AUDIO_QUEUE_BUFFER_MISMATCH, AS_AUDIO_QUEUE_DISPOSE_FAILED, AS_AUDIO_QUEUE_STOP_FAILED, AS_AUDIO_QUEUE_FLUSH_FAILED, AS_AUDIO_STREAMER_FAILED, AS_GET_AUDIO_TIME_FAILED, AS_AUDIO_BUFFER_TOO_SMALL } AudioStreamerErrorCode; extern NSString * const ASStatusChangedNotification; @interface AudioStreamer : NSObject { NSURL *url; // // Special threading consideration: // The audioQueue property should only ever be accessed inside a // synchronized(self) block and only *after* checking that ![self isFinishing] // AudioQueueRef audioQueue; AudioFileStreamID audioFileStream; // the audio file stream parser AudioStreamBasicDescription asbd; // description of the audio NSThread *internalThread; // the thread where the download and // audio file stream parsing occurs AudioQueueBufferRef audioQueueBuffer[kNumAQBufs]; // audio queue buffers AudioStreamPacketDescription packetDescs[kAQMaxPacketDescs]; // packet descriptions for enqueuing audio unsigned int fillBufferIndex; // the index of the audioQueueBuffer that is being filled UInt32 packetBufferSize; 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 NSInteger buffersUsed; NSDictionary *httpHeaders; AudioStreamerState state; AudioStreamerStopReason stopReason; AudioStreamerErrorCode errorCode; OSStatus err; bool discontinuous; // flag to indicate middle of the stream pthread_mutex_t queueBuffersMutex; // a mutex to protect the inuse flags pthread_cond_t queueBufferReadyCondition; // a condition varable for handling the inuse flags CFReadStreamRef stream; NSNotificationCenter *notificationCenter; UInt32 bitRate; // Bits per second in the file NSInteger dataOffset; // Offset of the first audio packet in the stream NSInteger fileLength; // Length of the file in bytes NSInteger seekByteOffset; // Seek offset within the file in bytes UInt64 audioDataByteCount; // Used when the actual number of audio bytes in // the file is known (more accurate than assuming // the whole file is audio) UInt64 processedPacketsCount; // number of packets accumulated for bitrate estimation UInt64 processedPacketsSizeTotal; // byte size of accumulated estimation packets double seekTime; BOOL seekWasRequested; double requestedSeekTime; double sampleRate; // Sample rate of the file (used to compare with // samples played by the queue for current playback // time) double packetDuration; // sample rate times frames per packet double lastProgress; // last calculated progress point #if TARGET_OS_IPHONE BOOL pausedByInterruption; #endif } @property AudioStreamerErrorCode errorCode; @property (readonly) AudioStreamerState state; @property (readonly) double progress; @property (readonly) double duration; @property (readwrite) UInt32 bitRate; @property (readonly) NSDictionary *httpHeaders; - (id)initWithURL:(NSURL *)aURL; - (void)start; - (void)stop; - (void)pause; - (BOOL)isPlaying; - (BOOL)isPaused; - (BOOL)isWaiting; - (BOOL)isIdle; - (void)seekToTime:(double)newSeekTime; - (double)calculatedBitRate; @end