IOS10 系統自帶的語音識別功能

前奏：

　　iOS 10 出來之後，我們開發者也可以使用類似Siri的功能。它是使用Siri裏面的一個語音識別框架Speech framework來處理siri的。現在， 讓我們來看看 一些 主要的代碼吧。 我們需要一個 UITextView 和 UIButton 就 能體現了。

 

實現：

• 第一步：定義屬性

@interface ViewController ()  <SFSpeechRecognizerDelegate>
@property (strong, nonatomic) UIButton *siriBtu;//siri按鈕
@property (strong, nonatomic) UITextView *siriTextView; //顯示語音轉化成的文本
@property (strong, nonatomic) SFSpeechRecognitionTask *recognitionTask; //語音識別任務
@property (strong, nonatomic)SFSpeechRecognizer *speechRecognizer; //語音識別器
@property (strong, nonatomic) SFSpeechAudioBufferRecognitionRequest *recognitionRequest; //識別請求
@property (strong, nonatomic)AVAudioEngine *audioEngine; //錄音引擎
@end

• 第二步：進行語音識別檢測

- (void)viewDidLoad {
    [super viewDidLoad];

 //設備識別語言爲中文
    NSLocale *cale = [[NSLocale alloc]initWithLocaleIdentifier:@"zh-CN"];
    self.speechRecognizer = [[SFSpeechRecognizer alloc]initWithLocale:cale];
    self.siriBtu.enabled = false;

　　//設置代理
    _speechRecognizer.delegate = self;

　　//發送語音認證請求(首先要判斷設備是否支持語音識別功能)
    [SFSpeechRecognizer requestAuthorization:^(SFSpeechRecognizerAuthorizationStatus status) {
        bool isButtonEnabled = false;
        switch (status) {
            case SFSpeechRecognizerAuthorizationStatusAuthorized:
                isButtonEnabled = true;
                NSLog(@"可以語音識別");
                break;
            case SFSpeechRecognizerAuthorizationStatusDenied:
                isButtonEnabled = false;
                NSLog(@"用戶被拒絕訪問語音識別");
                break;
            case SFSpeechRecognizerAuthorizationStatusRestricted:
                isButtonEnabled = false;
                NSLog(@"不能在該設備上進行語音識別");
                break;
            case SFSpeechRecognizerAuthorizationStatusNotDetermined:
                isButtonEnabled = false;
                NSLog(@"沒有授權語音識別");
                break;
            default:
                break;
        }
        self.siriBtu.enabled = isButtonEnabled;
    }];

　　//創建錄音引擎
    self.audioEngine = [[AVAudioEngine alloc]init];
}

• 第三步：按鈕的點擊事件

- (void)microphoneTap:(UIButton *)sender {
    if ([self.audioEngine isRunning]) {
        [self.audioEngine stop];
        [self.recognitionRequest endAudio];
        self.siriBtu.enabled = YES;
        [self.siriBtu setTitle:@"開始錄製" forState:UIControlStateNormal];
    }else{
        [self startRecording];
        [self.siriBtu setTitle:@"停止錄製" forState:UIControlStateNormal];
    }
}

• 第四步：開始錄製語音，並將語音轉爲文本

-(void)startRecording{
    if (self.recognitionTask) {
        [self.recognitionTask cancel];
        self.recognitionTask = nil;
    }
    AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    bool  audioBool = [audioSession setCategory:AVAudioSessionCategoryRecord error:nil];
    bool  audioBool1= [audioSession setMode:AVAudioSessionModeMeasurement error:nil];
    bool  audioBool2= [audioSession setActive:true withOptions:AVAudioSessionSetActiveOptionNotifyOthersOnDeactivation error:nil];
    if (audioBool || audioBool1||  audioBool2) {
        NSLog(@"可以使用");
    }else{
        NSLog(@"這裏說明有的功能不支持");
    }
    self.recognitionRequest = [[SFSpeechAudioBufferRecognitionRequest alloc]init];
    AVAudioInputNode *inputNode = self.audioEngine.inputNode;
    SFSpeechAudioBufferRecognitionRequest *recognitionRequest;
    self.recognitionRequest.shouldReportPartialResults = true;

　　//開始識別任務
    self.recognitionTask = [self.speechRecognizer recognitionTaskWithRequest:self.recognitionRequest resultHandler:^(SFSpeechRecognitionResult * _Nullable result, NSError * _Nullable error) {
        bool isFinal = false;
        if (result) {
            self.siriTextView.text = [[result bestTranscription] formattedString]; //語音轉文本
            isFinal = [result isFinal];
        }
        if (error || isFinal) {
            [self.audioEngine stop];
            [inputNode removeTapOnBus:0];
            self.recognitionRequest = nil;
            self.recognitionTask = nil;
            self.siriBtu.enabled = true;
        }
    }];
    AVAudioFormat *recordingFormat = [inputNode outputFormatForBus:0];
    [inputNode installTapOnBus:0 bufferSize:1024 format:recordingFormat block:^(AVAudioPCMBuffer * _Nonnull buffer, AVAudioTime * _Nonnull when) {
        [self.recognitionRequest appendAudioPCMBuffer:buffer];
    }];    
    [self.audioEngine prepare];
    bool audioEngineBool = [self.audioEngine startAndReturnError:nil];
    NSLog(@"%d",audioEngineBool);
    self.siriTextView.text = @"我是小冰！Siri 冰，你說我聽";
}

• 第五步：識別功能是否可用的改變通知

-(void)speechRecognizer:(SFSpeechRecognizer *)speechRecognizer availabilityDidChange:(BOOL)available{
    if(available){
        self.siriBtu.enabled = true;
    }else{
        self.siriBtu.enabled = false;
    }
}

爲原博主點贊：http://www.jianshu.com/p/b29069529bc2