Comment enregistrer de l'audio sur iPhone avec AVAudioRecorder?

Maintenant que l'iPhone 3.0 sdk est public, je pense que je peux poser cette question à ceux d'entre vous qui ont déjà joué avec le sdk 3.0. Je souhaite enregistrer de l'audio dans mon application, mais je souhaite utiliser AVAudioRecorder et non l'ancienne méthode d'enregistrement comme le montre l'exemple SpeakHere. Il n'y a pas d'exemples de la meilleure façon de faire cela dans le centre de développement iPhone et ne font référence qu'aux classes. Je suis un débutant dans le développement d'iPhone, donc je cherche un exemple simple pour me lancer. Merci d'avance.

En fait, il n'y a aucun exemple. Voici mon code de travail. L'enregistrement est déclenché par l'utilisateur qui appuie sur un bouton de la barre de navigation. L'enregistrement utilise une qualité cd (44100 échantillons), stéréo (2 canaux) pcm linéaire. Attention: si vous souhaitez utiliser un format différent, en particulier un format encodé, assurez-vous de bien comprendre comment définir les paramètres de l'AVAudioRecorder (lisez attentivement la documentation des types audio), sinon vous ne pourrez jamais l'initialiser correctement. Encore une chose. Dans le code, je ne montre pas comment gérer les données de mesure, mais vous pouvez le comprendre facilement. Enfin, notez que la méthode AVAudioRecorder deleteRecording à partir de cette écriture plante votre application. C'est pourquoi je supprime le fichier enregistré via le gestionnaire de fichiers. Lorsque l'enregistrement est terminé, j'enregistre l'audio enregistré sous NSData dans l'objet actuellement édité à l'aide de KVC.

#define DOCUMENTS_FOLDER [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"]


- (void) startRecording{

UIBarButtonItem *stopButton = [[UIBarButtonItem alloc] initWithTitle:@"Stop" style:UIBarButtonItemStyleBordered  target:self action:@selector(stopRecording)];
self.navigationItem.rightBarButtonItem = stopButton;
[stopButton release];

AVAudioSession *audioSession = [AVAudioSession sharedInstance];
NSError *err = nil;
[audioSession setCategory :AVAudioSessionCategoryPlayAndRecord error:&err];
if(err){
    NSLog(@"audioSession: %@ %d %@", [err domain], [err code], [[err userInfo] description]);
    return;
}
[audioSession setActive:YES error:&err];
err = nil;
if(err){
    NSLog(@"audioSession: %@ %d %@", [err domain], [err code], [[err userInfo] description]);
    return;
}

recordSetting = [[NSMutableDictionary alloc] init];

[recordSetting setValue :[NSNumber numberWithInt:kAudioFormatLinearPCM] forKey:AVFormatIDKey];
[recordSetting setValue:[NSNumber numberWithFloat:44100.0] forKey:AVSampleRateKey]; 
[recordSetting setValue:[NSNumber numberWithInt: 2] forKey:AVNumberOfChannelsKey];

[recordSetting setValue :[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];
[recordSetting setValue :[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsBigEndianKey];
[recordSetting setValue :[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsFloatKey];



// Create a new dated file
NSDate *now = [NSDate dateWithTimeIntervalSinceNow:0];
NSString *caldate = [now description];
recorderFilePath = [[NSString stringWithFormat:@"%@/%@.caf", DOCUMENTS_FOLDER, caldate] retain];

NSURL *url = [NSURL fileURLWithPath:recorderFilePath];
err = nil;
recorder = [[ AVAudioRecorder alloc] initWithURL:url settings:recordSetting error:&err];
if(!recorder){
    NSLog(@"recorder: %@ %d %@", [err domain], [err code], [[err userInfo] description]);
    UIAlertView *alert =
    [[UIAlertView alloc] initWithTitle: @"Warning"
                               message: [err localizedDescription]
                              delegate: nil
                     cancelButtonTitle:@"OK"
                     otherButtonTitles:nil];
    [alert show];
    [alert release];
    return;
}

//prepare to record
[recorder setDelegate:self];
[recorder prepareToRecord];
recorder.meteringEnabled = YES;

BOOL audioHWAvailable = audioSession.inputIsAvailable;
if (! audioHWAvailable) {
    UIAlertView *cantRecordAlert =
    [[UIAlertView alloc] initWithTitle: @"Warning"
                               message: @"Audio input hardware not available"
                              delegate: nil
                     cancelButtonTitle:@"OK"
                     otherButtonTitles:nil];
    [cantRecordAlert show];
    [cantRecordAlert release]; 
    return;
}

// start recording
[recorder recordForDuration:(NSTimeInterval) 10];

}

- (void) stopRecording{

[recorder stop];

NSURL *url = [NSURL fileURLWithPath: recorderFilePath];
NSError *err = nil;
NSData *audioData = [NSData dataWithContentsOfFile:[url path] options: 0 error:&err];
if(!audioData)
    NSLog(@"audio data: %@ %d %@", [err domain], [err code], [[err userInfo] description]);
[editedObject setValue:[NSData dataWithContentsOfURL:url] forKey:editedFieldKey];   

//[recorder deleteRecording];


NSFileManager *fm = [NSFileManager defaultManager];

err = nil;
[fm removeItemAtPath:[url path] error:&err];
if(err)
    NSLog(@"File Manager: %@ %d %@", [err domain], [err code], [[err userInfo] description]);



UIBarButtonItem *startButton = [[UIBarButtonItem alloc] initWithTitle:@"Record" style:UIBarButtonItemStyleBordered  target:self action:@selector(startRecording)];
self.navigationItem.rightBarButtonItem = startButton;
[startButton release];

}

- (void)audioRecorderDidFinishRecording:(AVAudioRecorder *) aRecorder successfully:(BOOL)flag
{

NSLog (@"audioRecorderDidFinishRecording:successfully:");
// your actions here

}

Bien que ce soit une question avec réponse (et un peu ancienne), j'ai décidé de publier mon code de travail complet pour ceux qui avaient du mal à trouver un bon exemple de jeu et d'enregistrement fonctionnel (prêt à l'emploi) - y compris encodé, pcm, lecture via haut-parleur , écrivez dans le fichier ici c'est:

AudioPlayerViewController.h:

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>

@interface AudioPlayerViewController : UIViewController {
AVAudioPlayer *audioPlayer;
AVAudioRecorder *audioRecorder;
int recordEncoding;
enum
{
    ENC_AAC = 1,
    ENC_ALAC = 2,
    ENC_IMA4 = 3,
    ENC_ILBC = 4,
    ENC_ULAW = 5,
    ENC_PCM = 6,
} encodingTypes;
}

-(IBAction) startRecording;
-(IBAction) stopRecording;
-(IBAction) playRecording;
-(IBAction) stopPlaying;

@end

AudioPlayerViewController.m:

#import "AudioPlayerViewController.h"

@implementation AudioPlayerViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    recordEncoding = ENC_AAC;
}

-(IBAction) startRecording
{
NSLog(@"startRecording");
[audioRecorder release];
audioRecorder = nil;

// Init audio with record capability
AVAudioSession *audioSession = [AVAudioSession sharedInstance];
[audioSession setCategory:AVAudioSessionCategoryRecord error:nil];

NSMutableDictionary *recordSettings = [[NSMutableDictionary alloc] initWithCapacity:10];
if(recordEncoding == ENC_PCM)
{
    [recordSettings setObject:[NSNumber numberWithInt: kAudioFormatLinearPCM] forKey: AVFormatIDKey];
    [recordSettings setObject:[NSNumber numberWithFloat:44100.0] forKey: AVSampleRateKey];
    [recordSettings setObject:[NSNumber numberWithInt:2] forKey:AVNumberOfChannelsKey];
    [recordSettings setObject:[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];
    [recordSettings setObject:[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsBigEndianKey];
    [recordSettings setObject:[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsFloatKey];   
}
else
{
    NSNumber *formatObject;

    switch (recordEncoding) {
        case (ENC_AAC): 
            formatObject = [NSNumber numberWithInt: kAudioFormatMPEG4AAC];
            break;
        case (ENC_ALAC):
            formatObject = [NSNumber numberWithInt: kAudioFormatAppleLossless];
            break;
        case (ENC_IMA4):
            formatObject = [NSNumber numberWithInt: kAudioFormatAppleIMA4];
            break;
        case (ENC_ILBC):
            formatObject = [NSNumber numberWithInt: kAudioFormatiLBC];
            break;
        case (ENC_ULAW):
            formatObject = [NSNumber numberWithInt: kAudioFormatULaw];
            break;
        default:
            formatObject = [NSNumber numberWithInt: kAudioFormatAppleIMA4];
    }

    [recordSettings setObject:formatObject forKey: AVFormatIDKey];
    [recordSettings setObject:[NSNumber numberWithFloat:44100.0] forKey: AVSampleRateKey];
    [recordSettings setObject:[NSNumber numberWithInt:2] forKey:AVNumberOfChannelsKey];
    [recordSettings setObject:[NSNumber numberWithInt:12800] forKey:AVEncoderBitRateKey];
    [recordSettings setObject:[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];
    [recordSettings setObject:[NSNumber numberWithInt: AVAudioQualityHigh] forKey: AVEncoderAudioQualityKey];
}

NSURL *url = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/recordTest.caf", [[NSBundle mainBundle] resourcePath]]];


NSError *error = nil;
audioRecorder = [[ AVAudioRecorder alloc] initWithURL:url settings:recordSettings error:&error];

if ([audioRecorder prepareToRecord] == YES){
    [audioRecorder record];
}else {
    int errorCode = CFSwapInt32HostToBig ([error code]); 
    NSLog(@"Error: %@ [%4.4s])" , [error localizedDescription], (char*)&errorCode); 

}
NSLog(@"recording");
}

-(IBAction) stopRecording
{
NSLog(@"stopRecording");
[audioRecorder stop];
NSLog(@"stopped");
}

-(IBAction) playRecording
{
NSLog(@"playRecording");
// Init audio with playback capability
AVAudioSession *audioSession = [AVAudioSession sharedInstance];
[audioSession setCategory:AVAudioSessionCategoryPlayback error:nil];

NSURL *url = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/recordTest.caf", [[NSBundle mainBundle] resourcePath]]];
NSError *error;
audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:&error];
audioPlayer.numberOfLoops = 0;
[audioPlayer play];
NSLog(@"playing");
}

-(IBAction) stopPlaying
{
NSLog(@"stopPlaying");
[audioPlayer stop];
NSLog(@"stopped");
}

- (void)dealloc
{
[audioPlayer release];
[audioRecorder release];
[super dealloc];
}

@end

J'espère que cela aidera certains d'entre vous.

J'ai téléchargé un exemple de projet. Vous pouvez jeter un oeil.

Enregistreur vocal

C'est vraiment utile. Le seul problème que j'ai eu était la taille du fichier son créé après l'enregistrement. J'avais besoin de réduire la taille du fichier, j'ai donc fait quelques changements dans les paramètres.

NSMutableDictionary *recordSetting = [[NSMutableDictionary alloc] init];
[recordSetting setValue :[NSNumber numberWithInt:kAudioFormatAppleIMA4] forKey:AVFormatIDKey];
[recordSetting setValue:[NSNumber numberWithFloat:16000.0] forKey:AVSampleRateKey];
[recordSetting setValue:[NSNumber numberWithInt: 1] forKey:AVNumberOfChannelsKey];

Taille du fichier réduite de 360 ​​Ko à seulement 25 Ko (enregistrement de 2 secondes).

J'ai essayé de faire fonctionner ce code pendant les 2 dernières heures et bien qu'il n'ait montré aucune erreur sur le simulateur, il y en avait une sur l'appareil.

Il s'avère, au moins dans mon cas, que l'erreur provenait du répertoire utilisé (bundle):

NSURL *url = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/recordTest.caf", [[NSBundle mainBundle] resourcePath]]];

Ce n'était pas inscriptible ou quelque chose comme ça ... Il n'y avait pas d'erreur sauf le fait que prepareToRecord a échoué ...

Je l'ai donc remplacé par:

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *recDir = [paths objectAtIndex:0];
NSURL *url = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/recordTest.caf", recDir]]

Cela fonctionne maintenant comme un charme.

J'espère que cela aide les autres.

Un grand merci à @Massimo Cafaro et Shaybc, j'ai pu accomplir les tâches ci-dessous

sous iOS 8:

Enregistrer l'audio et enregistrer

Lire l'enregistrement enregistré

1.Ajoutez "AVFoundation.framework" à votre projet

dans un fichier .h

2.Ajoutez ci-dessous la déclaration d'importation 'AVFoundation / AVFoundation.h'.

3.Définissez «AVAudioRecorderDelegate»

4.Créez une mise en page avec les boutons Enregistrer, Lire et leurs méthodes d'action

5.Définissez l'enregistreur et le lecteur, etc.

Voici l'exemple de code complet qui peut vous aider.

ViewController.h

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>

@interface ViewController : UIViewController <AVAudioRecorderDelegate>

@property(nonatomic,strong) AVAudioRecorder *recorder;
@property(nonatomic,strong) NSMutableDictionary *recorderSettings;
@property(nonatomic,strong) NSString *recorderFilePath;
@property(nonatomic,strong) AVAudioPlayer *audioPlayer;
@property(nonatomic,strong) NSString *audioFileName;

- (IBAction)startRecording:(id)sender;
- (IBAction)stopRecording:(id)sender;

- (IBAction)startPlaying:(id)sender;
- (IBAction)stopPlaying:(id)sender;

@end

Alors fais le travail

ViewController.m

#import "ViewController.h"

#define DOCUMENTS_FOLDER [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"]

@interface ViewController ()
@end

@implementation ViewController

@synthesize recorder,recorderSettings,recorderFilePath;
@synthesize audioPlayer,audioFileName;


#pragma mark - View Controller Life cycle methods
- (void)viewDidLoad
{
    [super viewDidLoad];
}
- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}


#pragma mark - Audio Recording
- (IBAction)startRecording:(id)sender
{
    AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    NSError *err = nil;
    [audioSession setCategory :AVAudioSessionCategoryPlayAndRecord error:&err];
    if(err)
    {
        NSLog(@"audioSession: %@ %ld %@", [err domain], (long)[err code], [[err userInfo] description]);
        return;
    }
    [audioSession setActive:YES error:&err];
    err = nil;
    if(err)
    {
        NSLog(@"audioSession: %@ %ld %@", [err domain], (long)[err code], [[err userInfo] description]);
        return;
    }
    
    recorderSettings = [[NSMutableDictionary alloc] init];
    [recorderSettings setValue :[NSNumber numberWithInt:kAudioFormatLinearPCM] forKey:AVFormatIDKey];
    [recorderSettings setValue:[NSNumber numberWithFloat:44100.0] forKey:AVSampleRateKey];
    [recorderSettings setValue:[NSNumber numberWithInt: 2] forKey:AVNumberOfChannelsKey];
    [recorderSettings setValue :[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];
    [recorderSettings setValue :[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsBigEndianKey];
    [recorderSettings setValue :[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsFloatKey];
    
    // Create a new audio file
    audioFileName = @"recordingTestFile";
    recorderFilePath = [NSString stringWithFormat:@"%@/%@.caf", DOCUMENTS_FOLDER, audioFileName] ;
    
    NSURL *url = [NSURL fileURLWithPath:recorderFilePath];
    err = nil;
    recorder = [[ AVAudioRecorder alloc] initWithURL:url settings:recorderSettings error:&err];
    if(!recorder){
        NSLog(@"recorder: %@ %ld %@", [err domain], (long)[err code], [[err userInfo] description]);
        UIAlertView *alert =
        [[UIAlertView alloc] initWithTitle: @"Warning" message: [err localizedDescription] delegate: nil
                         cancelButtonTitle:@"OK" otherButtonTitles:nil];
        [alert show];
        return;
    }
    
    //prepare to record
    [recorder setDelegate:self];
    [recorder prepareToRecord];
    recorder.meteringEnabled = YES;
    
    BOOL audioHWAvailable = audioSession.inputIsAvailable;
    if (! audioHWAvailable) {
        UIAlertView *cantRecordAlert =
        [[UIAlertView alloc] initWithTitle: @"Warning"message: @"Audio input hardware not available"
                                  delegate: nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
        [cantRecordAlert show];
        return;
    }
    
    // start recording
    [recorder recordForDuration:(NSTimeInterval) 60];//Maximum recording time : 60 seconds default
    NSLog(@"Recroding Started");
}

- (IBAction)stopRecording:(id)sender
{
    [recorder stop];
    NSLog(@"Recording Stopped");
}

- (void)audioRecorderDidFinishRecording:(AVAudioRecorder *) aRecorder successfully:(BOOL)flag
{
    NSLog (@"audioRecorderDidFinishRecording:successfully:");
}


#pragma mark - Audio Playing
- (IBAction)startPlaying:(id)sender
{
    NSLog(@"playRecording");
    
    AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    [audioSession setCategory:AVAudioSessionCategoryPlayback error:nil];
    
     NSURL *url = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/%@.caf", DOCUMENTS_FOLDER, audioFileName]];
    NSError *error;
    audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:&error];
    audioPlayer.numberOfLoops = 0;
    [audioPlayer play];
    NSLog(@"playing");
}
- (IBAction)stopPlaying:(id)sender
{
    [audioPlayer stop];
    NSLog(@"stopped");
}

@end

This is from Multimedia programming guide...

- (IBAction) recordOrStop: (id) sender {
if (recording) {
    [soundRecorder stop];
    recording = NO;
    self.soundRecorder = nil;
    [recordOrStopButton setTitle: @"Record" forState:
     UIControlStateNormal];
    [recordOrStopButton setTitle: @"Record" forState:
     UIControlStateHighlighted];
    [[AVAudioSession sharedInstance] setActive: NO error:nil];
} 
else {
    [[AVAudioSession sharedInstance]
     setCategory: AVAudioSessionCategoryRecord
     error: nil];
    NSDictionary *recordSettings =
    [[NSDictionary alloc] initWithObjectsAndKeys:[NSNumber numberWithFloat: 44100.0], AVSampleRateKey,
     [NSNumber numberWithInt: kAudioFormatAppleLossless], AVFormatIDKey,
     [NSNumber numberWithInt: 1], AVNumberOfChannelsKey,
     [NSNumber numberWithInt: AVAudioQualityMax],
     AVEncoderAudioQualityKey,
     nil];
    AVAudioRecorder *newRecorder =
    [[AVAudioRecorder alloc] initWithURL: soundFileURL
                                settings: recordSettings
                                   error: nil];
    [recordSettings release];
    self.soundRecorder = newRecorder;
    [newRecorder release];
    soundRecorder.delegate = self;
    [soundRecorder prepareToRecord];
    [soundRecorder record];
    [recordOrStopButton setTitle: @"Stop" forState: UIControlStateNormal];
    [recordOrStopButton setTitle: @"Stop" forState: UIControlStateHighlighted];
    recording = YES;
}
}

Dans le lien suivant, vous trouverez des informations utiles sur l'enregistrement avec AVAudioRecording. Dans ce lien dans la première partie «Utilisation de l'audio», il y a une ancre nommée «Enregistrement avec la classe AVAudioRecorder». cela vous conduit à l'exemple.

AudioVideo Conceptuel MultimédiaPG

Ok donc la réponse que j'ai obtenue m'a aidé dans la bonne direction et je suis très reconnaissant. Cela m'a aidé à comprendre comment enregistrer réellement sur l'iPhone, mais j'ai pensé que j'inclurais également du code utile que j'ai obtenu de la bibliothèque de référence iPhone:

Technologies audio et vidéo

J'ai utilisé ce code et l'ai ajouté assez facilement à l'exemple avTouch. Avec l'exemple de code ci-dessus et l'exemple de la bibliothèque de référence, j'ai pu le faire fonctionner assez bien.

pour le format wav en dessous du réglage audio

NSDictionary *audioSetting = [NSDictionary dictionaryWithObjectsAndKeys:
                              [NSNumber numberWithFloat:44100.0],AVSampleRateKey,
                              [NSNumber numberWithInt:2],AVNumberOfChannelsKey,
                              [NSNumber numberWithInt:16],AVLinearPCMBitDepthKey,
                              [NSNumber numberWithInt:kAudioFormatLinearPCM],AVFormatIDKey,
                              [NSNumber numberWithBool:NO], AVLinearPCMIsFloatKey, 
                              [NSNumber numberWithBool:0], AVLinearPCMIsBigEndianKey,
                              [NSNumber numberWithBool:NO], AVLinearPCMIsNonInterleaved,
                              [NSData data], AVChannelLayoutKey, nil];

réf: http://objective-audio.jp/2010/09/avassetreaderavassetwriter.html

DÉBUT

NSError *sessionError = nil;
[[AVAudioSession sharedInstance] setDelegate:self];
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayAndRecord error:&sessionError];
[[AVAudioSession sharedInstance] setActive: YES error: nil];
UInt32 doChangeDefaultRoute = 1;
AudioSessionSetProperty(kAudioSessionProperty_OverrideCategoryDefaultToSpeaker, sizeof(doChangeDefaultRoute), &doChangeDefaultRoute);

NSError *error = nil;
NSString *filename = [NSString stringWithFormat:@"%@.caf",FILENAME];
NSString *path = [[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"] stringByAppendingPathComponent:filename];
NSURL *soundFileURL = [NSURL fileURLWithPath:path];


NSDictionary *recordSettings = [NSDictionary dictionaryWithObjectsAndKeys:
                                [NSNumber numberWithInt: kAudioFormatMPEG4AAC], AVFormatIDKey,
                                [NSNumber numberWithInt:AVAudioQualityMedium],AVEncoderAudioQualityKey,
                                [NSNumber numberWithInt:AVAudioQualityMedium], AVSampleRateConverterAudioQualityKey,
                                [NSNumber numberWithInt: 1], AVNumberOfChannelsKey,
                                [NSNumber numberWithFloat:22050.0],AVSampleRateKey,
                                nil];

AVAudioRecorder *audioRecorder = [[AVAudioRecorder alloc]
                 initWithURL:soundFileURL
                 settings:recordSettings
                 error:&error];


if (!error && [audioRecorder prepareToRecord])
{
    [audioRecorder record];
}

ARRÊTEZ

[audioRecorder stop];
[audioRecorder release];
audioRecorder = nil;

-(void)viewDidLoad {
 // Setup audio session
    AVAudioSession *session = [AVAudioSession sharedInstance];
    [session setCategory:AVAudioSessionCategoryPlayAndRecord error:nil];

    // Define the recorder setting
    NSMutableDictionary *recordSetting = [[NSMutableDictionary alloc] init];

    [recordSetting setValue:[NSNumber numberWithInt:kAudioFormatMPEG4AAC] forKey:AVFormatIDKey];
    [recordSetting setValue:[NSNumber numberWithFloat:44100.0] forKey:AVSampleRateKey];
    [recordSetting setValue:[NSNumber numberWithInt: 2] forKey:AVNumberOfChannelsKey];

    // Initiate and prepare the recorder
    recorder = [[AVAudioRecorder alloc] initWithURL:outputFileURL settings:recordSetting error:NULL];
    recorder.delegate = self;
    recorder.meteringEnabled = YES;
    [recorder prepareToRecord];

}    

- (IBAction)btnRecordDidClicked:(UIButton *)sender {
        if (player1.playing) {
            [player1 stop];
        }

        if (!recorder.recording) {
            AVAudioSession *session = [AVAudioSession sharedInstance];
            [session setActive:YES error:nil];

            // Start recording
            [recorder record];
            [_recordTapped setTitle:@"Pause" forState:UIControlStateNormal];

        } else {

            // Pause recording
            [recorder pause];
            [_recordTapped setTitle:@"Record" forState:UIControlStateNormal];
        }

        [_stopTapped setEnabled:YES];
        [_playTapped setEnabled:NO];

    }

    - (IBAction)btnPlayDidClicked:(UIButton *)sender {
        if (!recorder.recording){
            player1 = [[AVAudioPlayer alloc] initWithContentsOfURL:recorder.url error:nil];
            [player1 setDelegate:self];
            [player1 play];
        }
    }

    - (IBAction)btnStopDidClicked:(UIButton *)sender {
        [recorder stop];
        AVAudioSession *audioSession = [AVAudioSession sharedInstance];
        [audioSession setActive:NO error:nil];
    }

    - (void) audioRecorderDidFinishRecording:(AVAudioRecorder *)avrecorder successfully:(BOOL)flag{
        [_recordTapped setTitle:@"play" forState:UIControlStateNormal];

        [_stopTapped setEnabled:NO];
        [_playTapped setEnabled:YES];

    }

Selon les réponses ci-dessus, j'ai apporté quelques modifications et j'ai obtenu la sortie correcte.

Étape 1: sous "inf.plist", ajoutez les autorisations d'utilisation du microphone ==>

  <key>NSMicrophoneUsageDescription</key>
  <string>${PRODUCT_NAME} Microphone Usage</string>

Étape 2:

1. Enregistrer le fichier audio enregistré dans le répertoire de documents local

2. Lire / arrêter l'enregistrement

3. Obtenir la durée du fichier audio enregistré

Voici le code source. Jetez-y un coup d'œil et utilisez-le.

ViewController.h

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>

@interface ViewController : UIViewController{
AVAudioPlayer *audioPlayer;
AVAudioRecorder *audioRecorder;
}

-(IBAction) startRecording;
-(IBAction) stopRecording;
-(IBAction) playRecording;
-(IBAction) stopPlaying;

@end

ViewController.m

#import "ViewController.h"
@interface ViewController () <AVAudioRecorderDelegate, AVAudioPlayerDelegate>

@end

@implementation ViewController

- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}

-(IBAction) startRecording{
// Setup audio session
AVAudioSession *audioSession = [AVAudioSession sharedInstance];
NSError *err = nil;
[audioSession setCategory :AVAudioSessionCategoryPlayAndRecord error:&err];
if(err)
{
    NSLog(@"audioSession: %@ %ld %@", [err domain], (long)[err code], [[err userInfo] description]);
    return;
}
[audioSession setActive:YES error:&err];
err = nil;
if(err)
{
    NSLog(@"audioSession: %@ %ld %@", [err domain], (long)[err code], [[err userInfo] description]);
    return;
}
AVAudioSessionRecordPermission permissionStatus = [audioSession recordPermission];
switch (permissionStatus) {
    case AVAudioSessionRecordPermissionUndetermined:{
        [[AVAudioSession sharedInstance] requestRecordPermission:^(BOOL granted) {
            // CALL YOUR METHOD HERE - as this assumes being called only once from user interacting with permission alert!
            if (granted) {
                // Microphone enabled code
                NSLog(@"Mic permission granted.  Call method for granted stuff.");
                [self startRecordingAudioSound];
            }
            else {
                // Microphone disabled code
                NSLog(@"Mic permission indeterminate. Call method for indeterminate stuff.");
                //        UIApplication.sharedApplication().openURL(NSURL(string: UIApplicationOpenSettingsURLString)!)
            }
        }];
        break;
    }
    case AVAudioSessionRecordPermissionDenied:
        // direct to settings...
        NSLog(@"Mic permission denied. Call method for denied stuff.");

        break;
    case AVAudioSessionRecordPermissionGranted:
        // mic access ok...
        NSLog(@"Mic permission granted.  Call method for granted stuff.");
        [self startRecordingAudioSound];
        break;
    default:
        // this should not happen.. maybe throw an exception.
        break;
}
}

#pragma mark - Audio Recording
- (BOOL)startRecordingAudioSound{
NSError *error = nil;
NSMutableDictionary *recorderSettings = [[NSMutableDictionary alloc] init];
[recorderSettings setValue :[NSNumber numberWithInt:kAudioFormatLinearPCM] forKey:AVFormatIDKey];
[recorderSettings setValue:[NSNumber numberWithFloat:44100.0] forKey:AVSampleRateKey];
[recorderSettings setValue:[NSNumber numberWithInt: 2] forKey:AVNumberOfChannelsKey];
[recorderSettings setValue :[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];
[recorderSettings setValue :[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsBigEndianKey];
[recorderSettings setValue :[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsFloatKey];

// Create a new audio file
NSArray *searchPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentPath_ = [searchPaths objectAtIndex: 0];
NSString *pathToSave = [documentPath_ stringByAppendingPathComponent:[self dateString]];
NSLog(@"the path is %@",pathToSave);

// File URL
NSURL *url = [NSURL fileURLWithPath:pathToSave];//FILEPATH];

//Save recording path to preferences
NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
[prefs setURL:url forKey:@"Test1"];
[prefs synchronize];

audioRecorder = [[AVAudioRecorder alloc] initWithURL:url settings:recorderSettings error:&error];
if (!audioRecorder)
{
    NSLog(@"Error establishing recorder: %@", error.localizedFailureReason);
    return NO;
}

// Initialize degate, metering, etc.
audioRecorder.delegate = self;
audioRecorder.meteringEnabled = YES;
//self.title = @"0:00";

if (![audioRecorder prepareToRecord])
{
    NSLog(@"Error: Prepare to record failed");
    //[self say:@"Error while preparing recording"];
    return NO;
}

if (![audioRecorder record])
{
    NSLog(@"Error: Record failed");
    //  [self say:@"Error while attempting to record audio"];
    return NO;
}
NSLog(@"Recroding Started");
return YES;
}

#pragma mark - AVAudioRecorderDelegate
- (void) audioRecorderDidFinishRecording:(AVAudioRecorder *)avrecorder successfully:(BOOL)flag{
NSLog (@"audioRecorderDidFinishRecording:successfully:");
}

#pragma mark - AVAudioPlayerDelegate
- (void) audioPlayerDidFinishPlaying:(AVAudioPlayer *)player successfully:(BOOL)flag{
NSLog (@"audioPlayerDidFinishPlaying:successfully:");
}

- (NSString *) dateString {
// return a formatted string for a file name
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
formatter.dateFormat = @"ddMMMYY_hhmmssa";
return [[formatter stringFromDate:[NSDate date]]stringByAppendingString:@".aif"];
}

-(IBAction) stopRecording{
NSLog(@"stopRecording");
[audioRecorder stop];
NSLog(@"stopped");
}

-(IBAction) playRecording{
//Load recording path from preferences
NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
NSURL *temporaryRecFile = [prefs URLForKey:@"Test1"];

//Get Duration of Audio File
AVURLAsset* audioAsset = [AVURLAsset URLAssetWithURL:temporaryRecFile options:nil];
CMTime audioDuration = audioAsset.duration;
float audioDurationSeconds = CMTimeGetSeconds(audioDuration);
NSLog(@"Duration Of Audio: %f", audioDurationSeconds);

audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:temporaryRecFile error:nil];
audioPlayer.delegate = self;
[audioPlayer setNumberOfLoops:0];
audioPlayer.volume = 1;
[audioPlayer prepareToPlay];
[audioPlayer play];
NSLog(@"playing");
}

-(IBAction) stopPlaying{
NSLog(@"stopPlaying");
[audioPlayer stop];
NSLog(@"stopped");
 }

 @end