AudioServicesPlaySystemSound while AVCaptureSession is active

Question

I'm developing a recording application and I want to play a sound when the recording starts.

Unfortunately it appears that since iOS 5 it's not possible to play a system sound when a AVCaptureSession with an audio device is active.

Here's the relevant part of the code I'm using

- (void)viewDidLoad {
    [super viewDidLoad];

    NSURL * soundURL = [[NSBundle mainBundle] URLForResource:@"recording-starts" withExtension:@"aif"];
    AudioServicesCreateSystemSoundID((__bridge CFURLRef)soundURL, &_recStartSound);

    //...

    if ([self.captureManager setupSession]) {
        // ... 

        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
            [self.captureManager.session startRunning];
        });

        // ...                    
    }
}

Later on, I just call AudioServicesPlaySystemSound(_recStartSound) and nothing goes on. However if I make the same call before the session setup, the sound plays as expected.

I found this bug report, which is exactly relevant to my problem, as well as this and this question, but I couldn't find any workaround in none of them.

How can I play a short sound right before starting the AV recording?

This is a very similar previous question: http://stackoverflow.com/questions/16309802/play-system-sound-while-recording-video-audio — David Elliman, Aug 08 '13 at 14:07
can anyone please help me with this question http://stackoverflow.com/questions/21059607/how-to-use-vibration-while-recording-iphone5-ios — BhavikKama, Jan 11 '14 at 07:04

score 1 · Answer 1 · answered Aug 08 '13 at 19:38

1

Play the sound using AVAudioPlayer instead.

answered Aug 08 '13 at 19:38

sc0rp10n

1,118
7
8

I don't understand why this is voted down. This actually works and solves what the question is asking about (play a sound while an AVCaptureSession is active). – simonfi Aug 30 '14 at 11:06

score 0 · Answer 2 · edited May 23 '17 at 11:58

See Are there any other iOS system sounds available other than 'tock'?

After some trial and error with system sounds available, on iOS 8.1.3 / iPhone 6 I was able to play these two:

AudioServicesPlaySystemSound(1114);

and

AudioServicesPlaySystemSound(1113);

requires only one line of code to play the sound after linking:

AudioToolbox/AudioToolbox.h

(see above link for more details)

And here's a partial-list of sounds available (from the comments in the above) http://iphonedevwiki.net/index.php/AudioServices

score -1 · Answer 3 · answered Aug 30 '14 at 11:12

Extending sc0rp10n's answer, the changes to the code in the question would simply be:

Initializing the sound player (_recStartSound being of type AVAudioPlayer*):

- (void)viewDidLoad {
    [super viewDidLoad];

    NSURL * soundURL = [[NSBundle mainBundle] URLForResource:@"recording-starts" withExtension:@"aif"];
    _recStartSound = [[AVAudioPlayer alloc] initWithContentsOfURL: soundURL error: NULL];

    ...
}

When you want to play the sound:

[_recStartSound play];

AudioServicesPlaySystemSound while AVCaptureSession is active

3 Answers3