AVSpeechSynthesizer 文本合成语音

官方文档

AVSpeechSynthesizer 在iOS 系统 将文本转化语音。在MacOS 中使用NSSpeechSynthesizer 。

AVSpeechSynthesizer * synthesizer = [[AVSpeechSynthesizer alloc] init]  ; 
AVSpeechUtterance * utterance = [AVSpeechUtterance speechUtteranceWithString：@"官方文档" ] ;
utterance.volume = 1.0 ; // 音量 0.0 - 1.0 之间
utterance.voice =  [AVSpeechSynthesisVoice voiceWithLanguage:AVSpeechSynthesisVoice.currentLanguageCode] ;        // 获取当前语言的声音 
utterance.rate = 0.5 ;        // 说话的速度
utterance.pitchMultiplier = 0.8 ; // 发出声音的基线音调。 [0.5 - 2] 默认 = 1
[synthesizer speakUtterance:utterance] ;

AVSpeechSynthesizer 中的属性和方法

@interface AVSpeechSynthesizer : NSObject

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

@property(nonatomic, readonly, getter=isSpeaking) BOOL speaking;
@property(nonatomic, readonly, getter=isPaused) BOOL paused;

// 往AVSpeechSynthesizer 添加语音，将语音添加到队列中，没有播放语音的话直接播放。
- (void)speakUtterance:(AVSpeechUtterance *)utterance; 
- (BOOL)stopSpeakingAtBoundary: (AVSpeechBoundary)boundary; // 停止语音 
- (BOOL)pauseSpeakingAtBoundary:(AVSpeechBoundary)boundary; // 暂停语音 
- (BOOL)continueSpeaking; // 继续语音播放 

@property(nonatomic, retain, nullable) NSArray<AVAudioSessionChannelDescription *> *outputChannels
 API_AVAILABLE(ios(10.0), watchos(3.0), tvos(10.0));

@end

AVSpeechUtterance 中的属性和方法

@interface AVSpeechUtterance : NSObject<NSCopying, NSSecureCoding>
+ (instancetype)speechUtteranceWithString:(NSString *)string; // 根据 字符串 创建  
+ (instancetype)speechUtteranceWithAttributedString:(NSAttributedString *)string 
API_AVAILABLE(ios(10.0), watchos(3.0), tvos(10.0));

- (instancetype)initWithString:(NSString *)string;
- (instancetype)initWithAttributedString:(NSAttributedString *)string API_AVAILABLE(ios(10.0), watchos(3.0), tvos(10.0));

@property(nonatomic, retain, nullable) AVSpeechSynthesisVoice *voice;  // 播放的声音 
@property(nonatomic, readonly) NSString *speechString;
@property(nonatomic, readonly) NSAttributedString *attributedSpeechString 
API_AVAILABLE(ios(10.0), watchos(3.0), tvos(10.0));


@property(nonatomic) float rate;          // 值固定在  AVSpeechUtteranceMinimumSpeechRate 和 AVSpeechUtteranceMaximumSpeechRate 之间。
@property(nonatomic) float pitchMultiplier;  // 发出声音的基线音调。 默认为1 值在0.5 - 2 之间。  
@property(nonatomic) float volume;       // 音量值在 0- 1 之间。 

@property(nonatomic) NSTimeInterval preUtteranceDelay;    // Default is 0.0
@property(nonatomic) NSTimeInterval postUtteranceDelay;   // Default is 0.0
@end