iOS 播放pcm文件

直接代码

#import <Foundation/Foundation.h>

@class LYPlayer;
@protocol LYPlayerDelegate <NSObject>

- (void)onPlayToEnd:(LYPlayer *)player;

@end


@interface LYPlayer : NSObject

@property (nonatomic, weak) id<LYPlayerDelegate> delegate;

- (void)play;

- (double)getCurrentTime;

@end

#import "LYPlayer.h"
#import <AudioUnit/AudioUnit.h>
#import <AVFoundation/AVFoundation.h>
#import <assert.h>

const uint32_t CONST_BUFFER_SIZE = 0x10000;

#define INPUT_BUS 1
#define OUTPUT_BUS 0

@implementation LYPlayer
{
    AudioUnit audioUnit;
    AudioBufferList *buffList;
    
    NSInputStream *inputSteam;
}

- (void)play {
    [self initPlayer];
    AudioOutputUnitStart(audioUnit);
}


- (double)getCurrentTime {
    Float64 timeInterval = 0;
    if (inputSteam) {
        
    }
    
    return timeInterval;
}



- (void)initPlayer {
    // open pcm stream
    NSString *document=[NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) objectAtIndex:0];
    
    NSString *folder =[document stringByAppendingPathComponent:@"asr.pcm"];
//    NSURL *url = [[NSBundle mainBundle] URLForResource:@"abc" withExtension:@"pcm"];
//    NSURL *url = [NSURL URLWithString:folder];
    
//    inputSteam = [NSInputStream inputStreamWithURL:url];
    inputSteam = [NSInputStream inputStreamWithFileAtPath:folder];
    if (!inputSteam) {
        NSLog(@"打开文件失败 %@", folder);
    }
    else {
        [inputSteam open];
    }
    
    NSError *error = nil;
    OSStatus status = noErr;
    
    // set audio session
    AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    [audioSession setCategory:AVAudioSessionCategoryPlayback error:&error];
    
    AudioComponentDescription audioDesc;
    audioDesc.componentType = kAudioUnitType_Output;
    audioDesc.componentSubType = kAudioUnitSubType_RemoteIO;
    audioDesc.componentManufacturer = kAudioUnitManufacturer_Apple;
    audioDesc.componentFlags = 0;
    audioDesc.componentFlagsMask = 0;
    
    AudioComponent inputComponent = AudioComponentFindNext(NULL, &audioDesc);
    AudioComponentInstanceNew(inputComponent, &audioUnit);
    
    // buffer
    buffList = (AudioBufferList *)malloc(sizeof(AudioBufferList));
    buffList->mNumberBuffers = 1;
    buffList->mBuffers[0].mNumberChannels = 1;
    buffList->mBuffers[0].mDataByteSize = CONST_BUFFER_SIZE;
    buffList->mBuffers[0].mData = malloc(CONST_BUFFER_SIZE);
    
    //audio property
    UInt32 flag = 1;
    if (flag) {
        status = AudioUnitSetProperty(audioUnit,
                                      kAudioOutputUnitProperty_EnableIO,
                                      kAudioUnitScope_Output,
                                      OUTPUT_BUS,
                                      &flag,
                                      sizeof(flag));
    }
    if (status) {
        NSLog(@"AudioUnitSetProperty error with status:%d", status);
    }
    
    // format
    AudioStreamBasicDescription outputFormat;
    memset(&outputFormat, 0, sizeof(outputFormat));
    outputFormat.mSampleRate       = 16000; // 采样率16000
    outputFormat.mFormatID         = kAudioFormatLinearPCM; // PCM格式
    outputFormat.mFormatFlags      = kLinearPCMFormatFlagIsSignedInteger; // 整形
    outputFormat.mFramesPerPacket  = 1; // 每帧只有1个packet
    outputFormat.mChannelsPerFrame = 1; // 声道数
    outputFormat.mBytesPerFrame    = 2; // 每帧只有2个byte 声道*位深*Packet数
    outputFormat.mBytesPerPacket   = 2; // 每个Packet只有2个byte
    outputFormat.mBitsPerChannel   = 16; // 位深
    [self printAudioStreamBasicDescription:outputFormat];

    status = AudioUnitSetProperty(audioUnit,
                                  kAudioUnitProperty_StreamFormat,
                                  kAudioUnitScope_Input,
                                  OUTPUT_BUS,
                                  &outputFormat,
                                  sizeof(outputFormat));
    if (status) {
        NSLog(@"AudioUnitSetProperty eror with status:%d", status);
    }
    
    
    // callback
    AURenderCallbackStruct playCallback;
    playCallback.inputProc = PlayCallback;
    playCallback.inputProcRefCon = (__bridge void *)self;
    AudioUnitSetProperty(audioUnit,
                         kAudioUnitProperty_SetRenderCallback,
                         kAudioUnitScope_Input,
                         OUTPUT_BUS,
                         &playCallback,
                         sizeof(playCallback));
    
    
    OSStatus result = AudioUnitInitialize(audioUnit);
    NSLog(@"result %d", result);
}


static OSStatus PlayCallback(void *inRefCon,
                             AudioUnitRenderActionFlags *ioActionFlags,
                             const AudioTimeStamp *inTimeStamp,
                             UInt32 inBusNumber,
                             UInt32 inNumberFrames,
                             AudioBufferList *ioData) {
    LYPlayer *player = (__bridge LYPlayer *)inRefCon;
    
    ioData->mBuffers[0].mDataByteSize = (UInt32)[player->inputSteam read:ioData->mBuffers[0].mData maxLength:(NSInteger)ioData->mBuffers[0].mDataByteSize];;
    NSLog(@"out size: %d", ioData->mBuffers[0].mDataByteSize);
    
    if (ioData->mBuffers[0].mDataByteSize <= 0) {
        dispatch_async(dispatch_get_main_queue(), ^{
            [player stop];
        });
    }
    return noErr;
}


- (void)stop {
    AudioOutputUnitStop(audioUnit);
    if (buffList != NULL) {
        if (buffList->mBuffers[0].mData) {
            free(buffList->mBuffers[0].mData);
            buffList->mBuffers[0].mData = NULL;
        }
        free(buffList);
        buffList = NULL;
    }
    
    if (self.delegate && [self.delegate respondsToSelector:@selector(onPlayToEnd:)]) {
        __strong typeof (LYPlayer) *player = self;
        [self.delegate onPlayToEnd:player];
    }
    
    [inputSteam close];
}

- (void)dealloc {
    AudioOutputUnitStop(audioUnit);
    AudioUnitUninitialize(audioUnit);
    AudioComponentInstanceDispose(audioUnit);
    
    if (buffList != NULL) {
        free(buffList);
        buffList = NULL;
    }
}


- (void)printAudioStreamBasicDescription:(AudioStreamBasicDescription)asbd {
    char formatID[5];
    UInt32 mFormatID = CFSwapInt32HostToBig(asbd.mFormatID);
    bcopy (&mFormatID, formatID, 4);
    formatID[4] = '\0';
    printf("Sample Rate:         %10.0f\n",  asbd.mSampleRate);
    printf("Format ID:           %10s\n",    formatID);
    printf("Format Flags:        %10X\n",    (unsigned int)asbd.mFormatFlags);
    printf("Bytes per Packet:    %10d\n",    (unsigned int)asbd.mBytesPerPacket);
    printf("Frames per Packet:   %10d\n",    (unsigned int)asbd.mFramesPerPacket);
    printf("Bytes per Frame:     %10d\n",    (unsigned int)asbd.mBytesPerFrame);
    printf("Channels per Frame:  %10d\n",    (unsigned int)asbd.mChannelsPerFrame);
    printf("Bits per Channel:    %10d\n",    (unsigned int)asbd.mBitsPerChannel);
    printf("\n");
}
@end

使用
导入头文件 #import "LYPlayer.h"
添加代理 LYPlayerDelegate

player = [[LYPlayer alloc] init];
    player.delegate = self;
    [player play];

- (void)onPlayToEnd:(LYPlayer *)lyPlayer {
    
    player = nil;
}