如何使用 AVAudioRecorder 在 iPhone 上录制音频？

Question

既然 iPhone 3.0 SDK 已经公开，我想我可以向那些已经使用过 3.0 SDK 的人问这个问题。 我想在我的应用程序中录制音频，但我想使用 AVAudioRecorder 而不是示例 SpeakHere 所示的旧式录制方式。 iPhone 开发中心没有任何关于如何最好地做到这一点的示例，仅参考了这些类。 我是 iPhone 开发的新手，所以我正在寻找一个简单的示例来帮助我入门。

Answer 1

-(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];

    }

Answer 2

根据上面的答案，我做了一些更改，并得到了正确的输出。

第1步：在“inf.plist”下添加麦克风使用权限==>

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

第2步：

1. 将录音音频文件保存到本地文档目录

2. 播放/停止录音

3. 获取保存的音频文件的持续时间

这是源代码。 请看一次并使用它。

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

Answer 3

这些答案都是 Objective-C 中的，这里是 Swift 中的答案。 这里唯一未包含的是允许录制所需的 pList 麦克风权限。

17 条评论中列出了这些步骤

class ViewController: UIViewController {    

    var arrOfRecordingUrls: [URL]() // 0. this is for the recordings once you stop recording in step 15. What you do with the recordings afterwards is up to to you.

    var micRecorder: AVAudioRecorder? // 1. AVAudioRecorder instance that you will initialize every time you start to record in step 6
    
    override func viewDidLoad() {
        super.viewDidLoad()

        // 2. set the AudioSession - you should make sure that the user has accepted the microphone permissions in your info.pList sometime before this 
        do {
            try AVAudioSession.sharedInstance().setCategory(.playAndRecord, mode: .default, options: .defaultToSpeaker)
            try AVAudioSession.sharedInstance().setActive(true)

        } catch {
            print(error.debugDescription)
        }
    }

    // 3. recordButton - if the micRecorder is nil start a recording, if not then a recording is currently taking place so stop it 
    @IBAction func recordButtonTapped(_ sender: Any) {
    
        if micRecorder == nil {
    
            startMicRecording()
    
        } else  {
    
            stopMicRecording()
        }
    }

    // *** if the pList Mic Permissions aren't granted then this won't work ***
    func startMicRecording() {

        // 4. create audioSettings
        let myAudioSettings: [String:Any] = [AVFormatIDKey: kAudioFormatMPEG4AAC,
                                                 AVNumberOfChannelsKey: 2,
                                                 AVSampleRateKey: 44100.0,
                                                 AVEncoderBitRateKey: 64000,
                                                 AVEncoderAudioQualityKey: AVAudioQuality.min.rawValue
        ]

        // 5. create a file/url which will be where the recording is stored
        let dirPath = "\(NSTemporaryDirectory())_Recordings_\(UUID().uuidString).m4a"
        let fileURL = URL(fileURLWithPath: dirPath)

        do {

            // 6. initialize the micRecorder with the audio settings from step 4. and the file/url from step 5
            micRecorder = try AVAudioRecorder(url: fileURL, settings: myAudioSettings)

            micRecorder?.prepareToRecord() // 7. prepare the micRecorder

            micRecorder?.delegate = self // 8. set the delegate so that you can access the recording file/url from step 5 once you are done 

            micRecorder?.isMeteringEnabled = true // optional
    
            micRecorder?.record() // 9. call .record() to start recording

        } catch {
            print(error.localizedDescription)
        }
    }
    
    func stopMicRecording() {
    
        micRecorder?.stop() // 10. call .stop() to stop the recording. At this point the delegate methods from step 12/13/17 will be where the recording output (file/url from step 5) will end up

        micRecorder = nil // 11. set the micRecorder to nil
    }
}

// 12. set the AVAudioRecorderDelegate which is the .delegate = self from step 8
extension ViewController: AVAudioRecorderDelegate {

    // your recording should end up here
    func audioRecorderDidFinishRecording(_ recorder: AVAudioRecorder, successfully flag: Bool) {

        // 13. if the recording was successful this flag will be true
        if flag {

             // 14. the file/url from step 5 which is the recording
             let successfullyRecordedURL = recorder.url

             // 15. add the file/url to the array from step 0.    
             arrOfRecordingUrls.append(successfullyRecordedURL)

        } else {

            // 16. the flag was false something went wrong with the recording ???
        }
    }

    // 17. if an error occurs while encoding it will be reported to the delegate
    func audioRecorderEncodeErrorDidOccur(_ recorder: AVAudioRecorder, error: Error?) {

        guard let error = error else { return }
        print(error.localizedDescription)
    }
}

Answer 4

非常感谢@Massimo Cafaro和Shaybc
我能够

在 iOS 8 中实现以下任务：

录制音频和音频 保存

播放保存的录音

1.将“AVFoundation.framework”添加到项目的

.h文件中

2.添加以下导入语句“AVFoundation/AVFoundation.h”。

3.定义“AVAudioRecorderDelegate”

4.创建一个包含“录制”、“播放”按钮及其操作方法的布局

5.定义“录音机”和“播放器”等。

以下是完整的示例代码，可能会对您有所帮助。

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

然后做工作

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

Answer 5

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;
}
}

Answer 6

在以下链接中，您可以找到有关使用 AVAudioRecording 进行录音的有用信息。 在第一部分“使用音频”的这个链接中，有一个名为“使用 AVAudioRecorder 类进行录制”的锚点。 这会让你看到这个例子。

音频视频概念多媒体PG

Answer 7

好的，我得到的答案帮助我找到了正确的方向，我非常感激。 它帮助我弄清楚如何在 iPhone 上实际录制，但我想我还应该包含一些从 iPhone 参考库中获得的有用代码：

AudioandVideoTechnologies

我使用了此代码并将其添加到 avTouch例子相当容易。 通过上面的代码示例和参考库中的示例，我能够让它很好地工作。

Answer 8

对于下面的音频设置参考 wav 格式

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];

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

Answer 9

开始

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];
}

停止

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

Answer 10

虽然这是一个已回答的问题（而且有点旧），但我决定为其他发现很难找到良好工作（开箱即用）播放和录音示例的人发布我的完整工作代码 - 包括编码、pcm、通过扬声器播放，在此处写入文件：

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

希望这会对你们中的一些人有所帮助。

Answer 11

我已经上传了一个示例项目。 你可以看一下。

录音机

Answer 12

它真的很有帮助。 我遇到的唯一问题是录制后创建的声音文件的大小。 我需要减小文件大小，因此我对设置进行了一些更改。

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];

文件大小从 360kb 减少到仅 25kb（2 秒录制）。

Answer 13

在过去的 2 个小时里，我一直在尝试让这段代码正常工作，尽管模拟器上没有显示错误，但设备上却出现了错误。

事实证明，至少在我的情况下，错误来自使用的目录（捆绑包）：

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

它不可写或类似的东西...除了prepareToRecord失败的事实之外没有错误...

因此我将其替换为：

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

它现在就像魅力一样。

希望这对其他人有帮助。

Answer 14

事实上，根本没有例子。
这是我的工作代码。 用户按下导航栏上的按钮即可触发录制。
录音使用 CD 质量（44100 个样本）、立体声（2 通道）线性 PCM。 请注意：如果您想使用不同的格式，尤其是编码格式，请确保您完全了解如何设置 AVAudioRecorder 设置（仔细阅读音频类型文档），否则您将永远无法正确初始化它。 还有一件事。 在代码中，我没有展示如何处理计量数据，但您可以轻松弄清楚。
最后，请注意，在撰写本文时，AVAudioRecorder 方法 deleteRecording 会使您的应用程序崩溃。 这就是我通过文件管理器删除录制文件的原因。 录制完成后，我使用 KVC 将录制的音频保存为当前编辑的对象中的 NSData。

#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

}