既然 iPhone 3.0 SDK 是公开的，我想我可以向那些已经在使用 3.0 SDK 的人提出这个问题。我想在我的应用程序中录制音频，但我想使用AVAudioRecorder，而不是像SpeakHere 示例所示的较旧的录制方式。 iPhone Dev Center 中没有任何关于如何最好地做到这一点的示例，仅引用了这些类。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。
【问题讨论】：
标签： ios objective-c iphone audio recording
实际上，根本没有例子。 这是我的工作代码。记录由用户按下导航栏上的按钮触发。 录音使用 cd 质量（44100 个样本）、立体声（2 通道）线性 pcm。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，但您可以轻松搞定。 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 NSData 在当前编辑的对象中。
#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
}
【讨论】：
虽然这是一个已回答的问题（而且有点老），但我决定将我的完整工作代码发布给那些发现很难找到好的工作（开箱即用）播放和录制示例的其他人 - 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
希望这对你们中的一些人有所帮助。
【讨论】：
我已经上传了一个示例项目。你可以看看。
【讨论】：
真的很有帮助。我唯一的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，所以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（录制 2 秒）。
【讨论】：
在过去的 2 个小时里，我一直试图让这段代码正常工作，虽然它在模拟器上没有显示错误，但在设备上有一个错误。
事实证明，至少在我的情况下，错误来自使用的目录（捆绑）：
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]]
它现在就像一个魅力。
希望这对其他人有所帮助。
【讨论】：
非常感谢 @Massimo Cafaro 和 Shaybc 我能够完成以下任务
在 iOS 8 中：
录制音频并保存
播放保存的录音
1.将“AVFoundation.framework”添加到您的项目中
在.h文件中
2.在导入语句'AVFoundation/AVFoundation.h'下面添加。
3.定义“AVAudioRecorderDelegate”
4.使用录制、播放按钮及其操作方法创建布局
5.定义记录器和播放器等
这是完整的示例代码，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
然后在
中完成工作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
【讨论】：
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;
}
}
【讨论】：
在以下链接中，您可以找到有关使用 AVAudioRecording 进行录制的有用信息。在第一部分“使用音频”的此链接中，有一个名为“使用 AVAudioRecorder 类录制”的锚点。这将引导您进入示例。
【讨论】：
好的，所以我得到的答案帮助我朝着正确的方向前进，我非常感谢。它帮助我弄清楚了如何在 iPhone 上实际录制，但我想我还会包含一些从 iPhone 参考库中获得的有用代码：
我使用了这段代码并很容易地将其添加到 avTouch 示例中。使用上面的代码示例和参考库中的示例，我能够让它工作得很好。
【讨论】：
音频设置下的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];
参考： http://objective-audio.jp/2010/09/avassetreaderavassetwriter.html
【讨论】：
let recordSettings:[String:AnyObject] = [ AVFormatIDKey:Int(kAudioFormatLinearPCM), AVLinearPCMIsFloatKey:false, AVLinearPCMIsBigEndianKey:0, AVLinearPCMIsNonInterleaved:false, AVSampleRateKey:44100.0, AVNumberOfChannelsKey:2, AVEncoderBitRateKey:12800, AVLinearPCMBitDepthKey:16, AVEncoderAudioQualityKey:AVAudioQuality.Max.rawValue]
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;
【讨论】：
-(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];
}
【讨论】：
根据上述答案，我做了一些更改，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：
将录音文件保存到本地文档目录
播放/停止录制
这里是源代码。请看一下并使用它。
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
【讨论】：
-[NSUserDefaults synchronize]。来自Apple's documentation“这个方法是不必要的，不应该使用。”