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objective-cspeech-recognitiontext-to-speechspeech-to-text

Text To Speech And Speech To Text Recognition -->self - Recognition is occurring


I want to developing an app which should support speech to text and text to speech ,

i)Speech to Text- Procedure-i have used Speech framework for speech to text ,whenever i open a app and if i start speaking ,the app should recognize the voice and should convert the speech into text .This is working

ii)Text to Speech - Procedure -i have used AVFoundation and MediaPlayer library If user press the play button it should convert the text i.e,whatever appear in the screen into speech.Working now .

Here is the problem is am facing while processing text to speech ,the speech recognizer recognizes the playing voice and printing the words again in textbox.

Example- if i say "Hello Good Morning" it is printing in text box and then if i press a play button it is playing a voice Hello Good Morning but at this time speech to text recognize recognize this voice i mean self- recognition and it's printing "Hello Good Morning Hello Good Morning"

I want to stop the Speech To Text Process while processing the Text To Speech

For this , i have stopped speech recognition request while playing the speech here is the code,

@implementation ViewController
{
SFSpeechAudioBufferRecognitionRequest *recognitionRequest;
SFSpeechRecognitionTask *recognitionTask;
AVAudioEngine *audioEngine;
NSMutableArray *speechStringsArray;
BOOL SpeechToText;
NSString* resultString;
NSString *str ;
NSString *searchString;
NSString *textToSpeak;
}

- (void)viewDidLoad {
[super viewDidLoad];

//Speech To Text ****

speechStringsArray = [[NSMutableArray alloc]init];

// Initialize background audio session
NSError *error = NULL;
AVAudioSession *session = [AVAudioSession sharedInstance];
[session setCategory:AVAudioSessionCategoryPlayback error:&error];
if(error) {
    NSLog(@"@error: %@", error);
}
[session setActive:YES error:&error];
if (error) {
    NSLog(@"@error: %@", error);
}

// Enabled remote controls
[[UIApplication sharedApplication] beginReceivingRemoteControlEvents];

// Voice setup
self.voicePicker.delegate = self;
self.voice = [AVSpeechSynthesisVoice voiceWithLanguage:@"en-us"];
self.voices = [NSMutableArray arrayWithObjects:
               @{@"voice" : @"en-us", @"label" : @"American English (Female)"},
               @{@"voice" : @"en-au", @"label" : @"Australian English (Female)"},
               @{@"voice" : @"en-gb", @"label" : @"British English (Male)"},
               @{@"voice" : @"en-ie", @"label" : @"Irish English (Female)"},
               @{@"voice" : @"en-za", @"label" : @"South African English (Female)"},
               nil];

// Synthesizer setup
self.synthesizer = [[AVSpeechSynthesizer alloc] init];
self.synthesizer.delegate = self;

// UITextView delegate
self.textView.delegate = self;

// This notifcation is generated from the AppDelegate applicationDidBecomeActive method to make sure that if the play or pause button is updated in the background then the button will be updated in the toolbar
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(updateToolbar) name:@"updateToolbar" object:nil];
  }


-(void)viewDidAppear:(BOOL)animated
{

self.speechRecognizer = [[SFSpeechRecognizer alloc]initWithLocale:[NSLocale localeWithLocaleIdentifier:@"en-US en-UK"]];

self.speechRecognizer.delegate = self;
audioEngine = [[AVAudioEngine alloc]init];
[SFSpeechRecognizer requestAuthorization:^(SFSpeechRecognizerAuthorizationStatus authStatus) {
    switch (authStatus) {
        case SFSpeechRecognizerAuthorizationStatusAuthorized:
            //User gave access to speech recognition
            NSLog(@"Authorized");

            [self start_record];

            break;

        case SFSpeechRecognizerAuthorizationStatusDenied:
            //User denied access to speech recognition
            NSLog(@"AuthorizationStatusDenied");

            break;

        case SFSpeechRecognizerAuthorizationStatusRestricted:
            //Speech recognition restricted on this device
            NSLog(@"AuthorizationStatusRestricted");

            break;

        case SFSpeechRecognizerAuthorizationStatusNotDetermined:
            //Speech recognition not yet authorized

            break;

        default:
            NSLog(@"Default");
            break;
    }
}];

//MARK : Interface Builder Actions

  }

****coding for increase the speed and pitch****

  - (IBAction)handleSpeedStepper:(UIStepper *)sender
  {
double speedValue = self.speedStepper.value;
[self.speedValueLabel setText:[NSString stringWithFormat:@"%.1f", speedValue]];
   }

  - (IBAction)handlePitchStepper:(UIStepper *)sender
  {
double pitchValue = self.pitchStepper.value;
[self.pitchValueLabel setText:[NSString stringWithFormat:@"%.1f", pitchValue]];
   }

//Play button for text to speech - (IBAction)handlePlayPauseButton:(UIBarButtonItem *)sender {

 if (self.synthesizer.speaking && !self.synthesizer.paused) {
    if (self.pauseSettingSegmentedControl.selectedSegmentIndex == 0) {
        // Stop immediately
        [self.synthesizer pauseSpeakingAtBoundary:AVSpeechBoundaryImmediate];
    }
    else {
        // Stop at end of current word
        [self.synthesizer pauseSpeakingAtBoundary:AVSpeechBoundaryWord];

    }
    [self updateToolbarWithButton:@"play"];
    }
    else if (self.synthesizer.paused) {
    [self.synthesizer continueSpeaking];
    [self updateToolbarWithButton:@"pause"];
     }
    else {
    [self speakUtterance];
    [self updateToolbarWithButton:@"pause"];
    }
    }

//method for speech to text -(void)start_record{

    NSError * outError;
    AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    [audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:&outError];

     [audioSession setMode:AVAudioSessionModeMeasurement error:&outError];
     [audioSession setActive:YES withOptions:AVAudioSessionSetActiveOptionNotifyOthersOnDeactivation  error:&outError];
 recognitionRequest = [[SFSpeechAudioBufferRecognitionRequest alloc]init];
 AVAudioInputNode *inputNode = audioEngine.inputNode;

     if (recognitionRequest  == nil) {
     NSLog(@"Unable to created a SFSpeechAudioBufferRecognitionRequest object");
     }
     if (inputNode == nil) {
     NSLog(@"Audio engine has no input node ");}

     //configure request so that results are returned before audio recording is finished
    [recognitionRequest setShouldReportPartialResults:YES];
    // A recognition task represents a speech recognition session.
    //We keep a reference to the task so that it can be cancelled .


    recognitionTask = [self.speechRecognizer recognitionTaskWithRequest:recognitionRequest resultHandler:^(SFSpeechRecognitionResult * result, NSError *  error1) {

    BOOL isFinal = false;

    if ((result = result)) {


        NSString *speech = result.bestTranscription.formattedString;
        NSLog(@"the speech:%@",speech);

        // coding for fixing append string issue
        for (int i = 0 ;i <speechStringsArray.count;i++)
        {

            str = [speechStringsArray objectAtIndex:i];

            NSRange range = [speech rangeOfString:str options:NSCaseInsensitiveSearch];
            NSLog(@"found: %@", (range.location != NSNotFound) ? @"Yes" : @"No");

            if (range.location != NSNotFound) {

                resultString = [speech stringByReplacingCharactersInRange:range withString:@""];

                speech = resultString;

                NSLog(@" the result is : %@",resultString);

            }

        }

        //specific functions - space for second word
        if (resultString.length>0) {

             self.textView.text = [NSString stringWithFormat:@"%@%@",self.textView.text,resultString];


                [speechStringsArray addObject:resultString];        }

        //specific function space for first word -Working fine
        else
        {
            [speechStringsArray addObject:speech];
                self.textView.text = speech;

            }


        }

        NSLog(@" array %@",speechStringsArray);


        isFinal = result.isFinal;

    }


    if (error1 != nil || isFinal) {

        [audioEngine stop];
        [inputNode removeTapOnBus:0];
        recognitionRequest = nil;
        recognitionTask = nil;

        [self start_record];

        }}];

        AVAudioFormat *recordingFormat =  [inputNode outputFormatForBus:0];
        [inputNode installTapOnBus:0 bufferSize:1024 format:recordingFormat block:^(AVAudioPCMBuffer * _Nonnull buffer, AVAudioTime * _Nonnull when){
        [recognitionRequest appendAudioPCMBuffer:buffer];}
];
        NSError *error1;
        [audioEngine prepare];
        [audioEngine startAndReturnError:&error1];}

        - (void)speakUtterance
        {
        NSLog(@"speakUtterance");
        didStartSpeaking = NO;
        textToSpeak = [NSString stringWithFormat:@"%@", self.textView.text];
        AVSpeechUtterance *utterance = [[AVSpeechUtterance alloc] initWithString:textToSpeak];
        utterance.rate = self.speedStepper.value;
        utterance.pitchMultiplier = self.pitchStepper.value;
        utterance.voice = self.voice;
        [self.synthesizer speakUtterance:utterance];
        [self displayBackgroundMediaFields];
        }

        - (void)displayBackgroundMediaFields
        {
        MPMediaItemArtwork *artwork = [[MPMediaItemArtwork alloc] initWithImage:[UIImage imageNamed:@"Play"]];

         NSDictionary *info = @{ MPMediaItemPropertyTitle: self.textView.text,
                        MPMediaItemPropertyAlbumTitle: @"TextToSpeech App",
                        MPMediaItemPropertyArtwork: artwork};

         [MPNowPlayingInfoCenter defaultCenter].nowPlayingInfo = info;
         }

        - (void)updateToolbar
       {
      if (self.synthesizer.speaking && !self.synthesizer.paused) {
      [self updateToolbarWithButton:@"pause"];
      }
      else {
    [self updateToolbarWithButton:@"play"];
     }}

    - (void)updateToolbarWithButton:(NSString *)buttonType
    {

     //stopping the speech to text process 
     if (audioEngine.isRunning) {

    [audioEngine stop];

    [recognitionRequest endAudio];

}



     NSLog(@"updateToolbarWithButton: %@", buttonType);
     UIBarButtonItem *audioControl;
     if ([buttonType isEqualToString:@"play"]) {
     // Play
     audioControl = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemPlay target:self action:@selector(handlePlayPauseButton:)];
     }
     else {
    // Pause
    audioControl = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemPause target:self action:@selector(handlePlayPauseButton:)];
     }
     UIBarButtonItem *flexibleItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];

     [self.toolbar setItems:@[flexibleItem, audioControl, flexibleItem]];
     }

     - (void)remoteControlReceivedWithEvent:(UIEvent *)receivedEvent
     {
     NSLog(@"receivedEvent: %@", receivedEvent);
     if (receivedEvent.type == UIEventTypeRemoteControl) {
     switch (receivedEvent.subtype) {
     case UIEventSubtypeRemoteControlPlay:
            NSLog(@"UIEventSubtypeRemoteControlPlay");
            if (self.synthesizer.speaking) {
                [self.synthesizer continueSpeaking];
            }
            else {
                [self speakUtterance];
            }
            break;

            case UIEventSubtypeRemoteControlPause:
            NSLog(@"pause - UIEventSubtypeRemoteControlPause");

            if (self.pauseSettingSegmentedControl.selectedSegmentIndex == 0) {
                // Pause immediately
                [self.synthesizer pauseSpeakingAtBoundary:AVSpeechBoundaryImmediate];
            }
            else {
                // Pause at end of current word
                [self.synthesizer pauseSpeakingAtBoundary:AVSpeechBoundaryWord];
            }
            break;

        case UIEventSubtypeRemoteControlTogglePlayPause:
            if (self.synthesizer.paused) {
                NSLog(@"UIEventSubtypeRemoteControlTogglePlayPause");
                [self.synthesizer continueSpeaking];
            }
            else {
                NSLog(@"UIEventSubtypeRemoteControlTogglePlayPause");
                if (self.pauseSettingSegmentedControl.selectedSegmentIndex == 0)                   {
                    // Pause immediately
                    [self.synthesizer pauseSpeakingAtBoundary:AVSpeechBoundaryImmediate];
                }
                else {
                    // Pause at end of current word
                    [self.synthesizer pauseSpeakingAtBoundary:AVSpeechBoundaryWord];
                }
                }
                break;

        case UIEventSubtypeRemoteControlNextTrack:
            NSLog(@"UIEventSubtypeRemoteControlNextTrack - appropriate for playlists");
            break;

        case UIEventSubtypeRemoteControlPreviousTrack:
            NSLog(@"UIEventSubtypeRemoteControlPreviousTrack - appropriatefor playlists");
            break;

        default:
            break;
        }     
        }
         }

pragma mark UIPickerViewDelegate Methods

         - (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
          {
           return 1;
           }

           - (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
           {
           return self.voices.count;
            }

           - (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view
           {
            UILabel *rowLabel = [[UILabel alloc] init];
            NSDictionary *voice = [self.voices objectAtIndex:row];
            rowLabel.text = [voice objectForKey:@"label"];
            return rowLabel;
            }

            - (void)pickerView:(UIPickerView *)pickerView didSelectRow: (NSInteger)row inComponent:(NSInteger)component
            {
            NSDictionary *voice = [self.voices objectAtIndex:row];
            NSLog(@"new picker voice selected with label: %@", [voice objectForKey:@"label"]);
            self.voice = [AVSpeechSynthesisVoice voiceWithLanguage:[voice objectForKey:@"voice"]];
             }

pragma mark SpeechSynthesizerDelegate methods

        - (void)speechSynthesizer:(AVSpeechSynthesizer *)synthesizer didFinishSpeechUtterance:(AVSpeechUtterance *)utterance
        {
        // This is a workaround of a bug. When we change the voice the first time the speech utterence is set fails silently. We check that the method willSpeakRangeOfSpeechString is called and set didStartSpeaking to YES there. If this method is not called (silent fail) then we simply request to speak again.
         if (!didStartSpeaking) {
          [self speakUtterance];

         }
         else {
         [self updateToolbarWithButton:@"play"];

        NSLog(@"the text are:%@",self.textView.text);

        }}

        - (void)speechSynthesizer:(AVSpeechSynthesizer *)synthesizer willSpeakRangeOfSpeechString:(NSRange)characterRange utterance:(AVSpeechUtterance *)utterance
        {
didStartSpeaking = YES;
//[self setTextViewTextWithColoredCharacterRange:characterRange];

        }

        #pragma mark UITextViewDelegate Methods

        - (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text {

       if([text isEqualToString:@"\n"]) {
       [textView resignFirstResponder];
       return NO;
       }

       return YES;
       }

Solution

  • Dont initialize all the things in the ViewDidLoad. When You tap on button to convert text to speech, at that that time make the speech to text conversion object as nil also set the delegate the nil. Same things for the vice versa also.