Why is AVAudioRecorder prepareToRecord Failing?
I am trying to setup a basic controller that will record user audio input(voice). However, the AVAudioRecorder's prepareToRecord method is failing and I can't figure out why. I have setup the audio session in my app delegate and I do not receive an errors when I instantiate the AVAudioRecorder instance:
// App delegate snippet
AVAudioSession* audioSession = [AVAudioSession sharedInstance];
NSError* audioSessionError = nil;
[audioSession setCategory: AVAudioSessionCategoryPlayAndRecord
error: &audioSessionError];
if (audioSessionError) {
NSLog (@"Error setting audio category: %@", [audioSessionError localizedDescription]);
} else {
NSLog(@"No session errors for setting category");
}
[audioSession setActive:YES error:&audioSessionError];
if (audioSessionError) {
NSLog (@"Error activating audio session: %@", [audioSessionError localizedDescription]);
} else {
NSLog(@"no session errors for setActive");
}
// VIEW DID LOAD IN RECORDERCONTROLLER
- (void)viewDidLoad {
self.navigationItem.title = [NSString stringWithFormat:@"%@", [[MyAppDelegate loadApplicationPlist] valueForKey:@"recorderViewTitle"]];
self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone
target:self
action:@selector(dismiss)];
[self alertIfNoAudioInput];
[self createAVAudioRecorder];
minutesSecondsFormatter = [[SimpleMinutesSecondsFormatter alloc] init];
currentTimeUpdateTimer = [NSTimer scheduledTimerWithTimeInterval:0.1
target:self selector:@selector(updateAudioDisplay)
userInfo:NULL repeats:YES];
[super viewDidLoad];
}
// CREATE AVAUDIORECORDER
- (NSError *)createAVAudioRecorder {
NSError *recorderSetupError = nil;
[audioRecorder release];
audioRecorder = nil;
NSString *timestamp = [NSString stringWithFormat:@"%d", (long)[[NSDate date] timeIntervalSince1970]];
NSString *destinationString = [[MyAppDelegate getAppDocumentsDirectory] stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.caf", timestamp]];
NSLog(@"destinationString: %@", destinationString);
NSURL *destinationUrl = [NSURL fileURLWithPath: destinationString];
audioRecorder = [[AVAudioRecorder alloc] initWithURL:destinationUrl
settings:[[AVRecordSettings sharedInstance] getSettings]
error:&recorderSetupErro开发者_如何学Gor];
if (recorderSetupError) {
UIAlertView *cantRecordAlert =
[[UIAlertView alloc] initWithTitle:@"Can't record"
message:[recorderSetupError localizedDescription]
delegate:nil
cancelButtonTitle:@"OK"
otherButtonTitles:nil];
[cantRecordAlert show];
[cantRecordAlert release];
return recorderSetupError;
} else {
NSLog(@"no av setup error");
}
if ([audioRecorder prepareToRecord]) {
recordPauseButton.enabled = YES;
audioRecorder.delegate = self;
} else {
NSLog(@"couldn't prepare to record");
}
NSLog (@"recorderSetupError: %@", recorderSetupError);
return recorderSetupError;
}
The prepareToRecord also fails (silently, without an error) if the directory where you try to save the file doesn't exist. Use NSFileManager to check if the directory already exists.
It is failing because you did not initialize the AVAudioRecorder object using proper settings. Do this before initializing it:
NSDictionary *recordSettings =
[[NSDictionary alloc] initWithObjectsAndKeys:
[NSNumber numberWithFloat: 44100.0], AVSampleRateKey,
[NSNumber numberWithInt: kAudioFormatAppleLossless], AVFormatIDKey,
[NSNumber numberWithInt: 1], AVNumberOfChannelsKey,
[NSNumber numberWithInt: AVAudioQualityMax], AVEncoderAudioQualityKey,
nil];
then you can instantiate it using
audioRecorder = [[AVAudioRecorder alloc] initWithURL:destinationUrl
settings:recordSettings
error:&recorderSetupError];
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