ios AudioUnit bluetooth 錄音 播放 實現

ios AudioUnit bluetooth 錄音 播放 實現

因爲拍攝短視頻的時候有時候手機離主人比較遠的時候，這樣錄音效果就不好了， 爲了方便記錄聲音，則最好的方式就是使用藍牙耳機，但是ios關於藍牙耳機的使用特別少，以下是我總結的內容。

#import "XYRecorder.h"
#import <AVFoundation/AVFoundation.h>

#define INPUT_BUS 1
#define OUTPUT_BUS 0

AudioUnit audioUnit;
AudioBufferList *buffList;

@implementation XYRecorder

#pragma mark - init

- (instancetype)init {
    self = [super init];
    
    if (self) {
        AudioUnitInitialize(audioUnit);
        [self initRemoteIO];
    }
    
    return self;
}

- (void)initRemoteIO {
    [self initAudioSession];
    
    [self initBuffer];
    
    [self initAudioComponent];
    
    [self initFormat];
    
    [self initAudioProperty];
    
    [self initRecordeCallback];
    
    [self initPlayCallback];
}

- (void)initAudioSession {
    NSError *error;
    AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    
    [audioSession setCategory:AVAudioSessionCategoryPlayAndRecord withOptions:AVAudioSessionCategoryOptionAllowBluetooth error:&error];
    [audioSession setPreferredSampleRate:44100 error:&error];
    [audioSession setPreferredInputNumberOfChannels:1 error:&error];
    [audioSession setPreferredIOBufferDuration:0.023 error:&error];

}

- (void)initBuffer {
    UInt32 flag = 0;
    AudioUnitSetProperty(audioUnit,
                         kAudioUnitProperty_ShouldAllocateBuffer,
                         kAudioUnitScope_Output,
                         INPUT_BUS,
                         &flag,
                         sizeof(flag));
    
    buffList = (AudioBufferList*)malloc(sizeof(AudioBufferList));
    buffList->mNumberBuffers = 1;
    buffList->mBuffers[0].mNumberChannels = 1;
    
    buffList->mBuffers[0].mDataByteSize = 1024 * sizeof(short);
    buffList->mBuffers[0].mData = (short *)malloc(sizeof(short) * 1024);
}

- (void)initAudioComponent {
    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);
}

- (void)initFormat {
    AudioStreamBasicDescription audioFormat;
    audioFormat.mSampleRate = 44100;
    audioFormat.mFormatID = kAudioFormatLinearPCM;
    audioFormat.mFormatFlags = kAudioFormatFlagIsSignedInteger | kAudioFormatFlagIsPacked;
    audioFormat.mFramesPerPacket = 1;
    audioFormat.mChannelsPerFrame = 1;
    audioFormat.mBitsPerChannel = 16;
    audioFormat.mBytesPerPacket = 2;
    audioFormat.mBytesPerFrame = 2;
    
    AudioUnitSetProperty(audioUnit,
                         kAudioUnitProperty_StreamFormat,
                         kAudioUnitScope_Output,
                         OUTPUT_BUS,
                         &audioFormat,
                         sizeof(audioFormat));
    AudioUnitSetProperty(audioUnit,
                         kAudioUnitProperty_StreamFormat,
                         kAudioUnitScope_Input,
                         INPUT_BUS,
                         &audioFormat,
                         sizeof(audioFormat));
}

- (void)initRecordeCallback {
    AURenderCallbackStruct recordCallback;
    recordCallback.inputProc = RecordCallback;
    recordCallback.inputProcRefCon = (__bridge void *)self;
    AudioUnitSetProperty(audioUnit,
                         kAudioOutputUnitProperty_SetInputCallback,
                         kAudioUnitScope_Global,
                         INPUT_BUS,
                         &recordCallback,
                         sizeof(recordCallback));
}

- (void)initPlayCallback {
    AURenderCallbackStruct playCallback;
    playCallback.inputProc = PlayCallback;
    playCallback.inputProcRefCon = (__bridge void *)self;
    AudioUnitSetProperty(audioUnit,
                         kAudioUnitProperty_SetRenderCallback,
                         kAudioUnitScope_Global,
                         OUTPUT_BUS,
                         &playCallback,
                         sizeof(playCallback));
}

- (void)initAudioProperty {
    UInt32 flag = 1;
    
    AudioUnitSetProperty(audioUnit,
                         kAudioOutputUnitProperty_EnableIO,
                         kAudioUnitScope_Input,
                         INPUT_BUS,
                         &flag,
                         sizeof(flag));
    AudioUnitSetProperty(audioUnit,
                         kAudioOutputUnitProperty_EnableIO,
                         kAudioUnitScope_Input,
                         OUTPUT_BUS,
                         &flag,
                         sizeof(flag));

}

#pragma mark - callback function

static OSStatus RecordCallback(void *inRefCon,
                               AudioUnitRenderActionFlags *ioActionFlags,
                               const AudioTimeStamp *inTimeStamp,
                               UInt32 inBusNumber,
                               UInt32 inNumberFrames,
                               AudioBufferList *ioData)
{
    
    AudioUnitRender(audioUnit, ioActionFlags, inTimeStamp, inBusNumber, inNumberFrames, buffList);
    
    short *data = (short *)buffList->mBuffers[0].mData;
    NSLog(@"%d %d %d ", buffList->mBuffers[0].mDataByteSize, inBusNumber, inNumberFrames);
    
    return noErr;
}

static OSStatus PlayCallback(void *inRefCon,
                            AudioUnitRenderActionFlags *ioActionFlags,
                            const AudioTimeStamp *inTimeStamp,
                            UInt32 inBusNumber,
                            UInt32 inNumberFrames,
                            AudioBufferList *ioData) {
//    memcpy(ioData->mBuffers[0].mData, buffList->mBuffers[0].mData, buffList->mBuffers[0].mDataByteSize);
    AudioUnitRender(audioUnit, ioActionFlags, inTimeStamp, 1, inNumberFrames, ioData);
    
    return noErr;
}

#pragma mark - public methods

- (void)startRecorder {
    AudioOutputUnitStart(audioUnit);
}

- (void)stopRecorder {
    AudioOutputUnitStop(audioUnit);
}


@end