I am using AVAudioSession to detect whether an external mic is attached to the device I'm using (an iPad 2 in this case). However, the below call is returning nil when I have an external mic attached, and when I don't.
NSArray *availableInputs = [[AVAudioSession sharedInstance] availableInputs];
AVAudioSessionPortDescription *port = [availableInputs objectAtIndex:0];
I would have assumed that when the mic is not attached this would return a list including the internal mic alone, with the external microphone attached it would return a list including the internal mic and the external mic.
This thread indicates that it should be returning these sort of results (with an error in this case, but that seems irrelevant), so I'm confused as to why I'm not getting the correct output. Perhaps there's a flag that needs to be set to show that I'm using multi-route audio.
Any help would be appreciated.
I am creating an app that use google webrtc API. When I connect two devices into a session. I enable audio channel so that they can talk through the devices. I know that in the webrtc Library, they already setting the sessionMode to be VoiceChat, but I have to set the category to be playAndRecord myself as well because I want to play a ringTone sound when someone calls when the app is in the background.
So When I setting the audioSessionCatogory to PlayAndRecord, the app will freeze and the status bar will flash red for couple time before the connection is established.
I tried not to set category by myself and everything works fine, but I really need to do so in order to fulfill my goal of the app.
Does anyone know what the problem might be? I do not know if it is a problem of I am setting the category while the webrtc is setting it as well, or my code for setting the catergory is not correct.
So this is the code I use to change the catergory.
UInt32 value = kAudioSessionCategory_PlayAndRecord;
AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(value), &value);
value = YES;
AudioSessionSetProperty(kAudioSessionProperty_OverrideCategoryMixWithOthers, sizeof(value), &value);
AudioSessionSetProperty(kAudioSessionProperty_OverrideCategoryDefaultToSpeaker, sizeof(value), &value);
value = kAudioSessionMode_VoiceChat;
AudioSessionSetProperty(kAudioSessionProperty_Mode, sizeof(value), &value);
AudioSessionSetActive(YES);
I tried to use the AVAudioSession class intead, but that does not work out the way I want, so I am using this. Could this be a thread problem? Does this code need to be run in a specify thread?
Also, I am getting this Error when I switch Category:
ERROR: [0x8731000] >aurioc> 1455: AURemoteIO#0x17dbb020:
IOThread exiting with error 0x10004006
Thank you for all your helps
The iPhone 5 has three microphones - top front, top back, and bottom. I would like to record on all of them at the same time to do some signal processing. I've tried for several days unsuccessfully.
Using AVAudioSession, I can see the microphones:
NSLog(#"%#", [AVAudioSession sharedInstance].availableInputs);
"<AVAudioSessionPortDescription: 0x14554400, type = MicrophoneBuiltIn; name = iPhone Microphone; UID = Built-In Microphone; selectedDataSource = Back>"
NSLog(#"%#", [AVAudioSession sharedInstance].availableInputs[0].inputDataSources);
"<AVAudioSessionDataSourceDescription: 0x145afb00, ID = 1835216945; name = Bottom>",
"<AVAudioSessionDataSourceDescription: 0x145b1870, ID = 1835216946; name = Front>",
"<AVAudioSessionDataSourceDescription: 0x145b3650, ID = 1835216947; name = Back>"
I can use AVAudioSessionPortDescription -setPreferredDataSource:error: to record from one of the three. But I cannot record on more than one simultaneously. If I set the number of input channels to 2, I get two identical tracks from the same microphone.
AVAudioRecorder has a property channelAssignments which seems like it should work, but AVAudioSession inputNumberOfChannels and maximumInputNumberOfChannels are both 1. The property channelAssignments is designed for auxiliary microphones which have multiple channels.
I tried using the low-level AudioUnit, but I get the same result. I could not find any properties on AudioUnit to change the input source.
Any help would be appreciated.
My understanding, after all my research trying to do the same thing, is just what you've described - you can't prefer multiple data sources for the one device, thus you can't record from multiple built-in mics at once. If anyone can prove me wrong, I'd VERY much love to hear it!
Sidenote: I can't seem to run your code. As written, I get
Property availableInputs not found on object of type 'id'
Even after massaging what you've got into a format that doesn't require any explicit casts:
NSLog(#"%#", [[[AVAudioSession sharedInstance] availableInputs][0] inputDataSources]);
I get SIGABRT:
-[AVAudioSessionPortDescription inputDataSources]: unrecognized selector sent to instance 0xd59dbe0'
what SDK are you using that your code actually compiles, much less runs?
I'm trying to get audio in my app to play through the upper speaker on the iPhone, the one you press to your ear during a phone call. I know it's possible, because I've played a game from the App Store ("The Heist" by "tap tap tap") that simulates phone calls and does exactly that.
I've done a lot of research online, but I'm having a surprisingly hard time finding ANYONE who has even discussed the possibility. The overwhelming majority of posts seem to be about the handsfree speaker vs plugged-in earphones, (like this and this and this), rather than the upper "phone call" speaker vs the handsfree speaker. (Part of that problem might be not having a good name for it: "phone speaker" often means the handsfree speaker at the bottom of the device, etc, so it's hard to do a really well-targeted search). I've looked into Apple's Audio Session Category Route Overrides, but those again seem to (correct me if I'm wrong) deal only with the handsfree speaker at the bottom, not the speaker at the top of the phone.
I have found ONE post that seems to be about this: link. It even provides a bunch of code, so I thought I was home free, but now I can't seem to get the code to work. For simplicity I just copied the DisableSpeakerPhone method (which if I understand it correctly should be the one to re-route audio to the upper speaker) into my viewDidLoad to see if it would work, but the first "assert" line fails, and the audio continues to play out the bottom. (I also imported the AudioToolbox Framework, as suggested in the comment, so that isn't the problem.)
Here is the main block of code I'm working with (this is what I copied into my viewDidLoad to test), although there are a few more methods in the article I linked to:
void DisableSpeakerPhone () {
UInt32 dataSize = sizeof(CFStringRef);
CFStringRef currentRoute = NULL;
OSStatus result = noErr;
AudioSessionGetProperty(kAudioSessionProperty_AudioRoute, &dataSize, ¤tRoute);
// Set the category to use the speakers and microphone.
UInt32 sessionCategory = kAudioSessionCategory_PlayAndRecord;
result = AudioSessionSetProperty (
kAudioSessionProperty_AudioCategory,
sizeof (sessionCategory),
&sessionCategory
);
assert(result == kAudioSessionNoError);
Float64 sampleRate = 44100.0;
dataSize = sizeof(sampleRate);
result = AudioSessionSetProperty (
kAudioSessionProperty_PreferredHardwareSampleRate,
dataSize,
&sampleRate
);
assert(result == kAudioSessionNoError);
// Default to speakerphone if a headset isn't plugged in.
// Overriding the output audio route
UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_None;
dataSize = sizeof(audioRouteOverride);
AudioSessionSetProperty(
kAudioSessionProperty_OverrideAudioRoute,
dataSize,
&audioRouteOverride);
assert(result == kAudioSessionNoError);
AudioSessionSetActive(YES);
}
So my question is this: can anyone either A) help me figure out why that code doesn't work, or B) offer a better suggestion for being able to press a button and route the audio up to the upper speaker?
PS I am getting more and more familiar with iOS programming, but this is my first foray into the world of AudioSessions and such, so details and code samples are much appreciated! Thank you for your help!
UPDATE:
From the suggestion of "He Was" (below) I've removed the code quoted above and replaced it with:
[[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategoryPlayAndRecord error:nil];
[[AVAudioSession sharedInstance] setActive: YES error:nil];
at the beginning of viewDidLoad. It still isn't working, though, (by which I mean the audio is still coming out of the speaker at the bottom of the phone instead of the receiver at the top). Apparently the default behavior should be for AVAudioSessionCategoryPlayAndRecord to send audio out of the receiver on its own, so something is still wrong.
More specifically what I'm doing with this code is playing audio through the iPod Music Player (initialized right after the AVAudioSession lines above in viewDidLoad, for what it's worth):
_musicPlayer = [MPMusicPlayerController iPodMusicPlayer];
and the media for that iPod Music Player is chosen through an MPMediaPickerController:
- (void) mediaPicker: (MPMediaPickerController *) mediaPicker didPickMediaItems: (MPMediaItemCollection *) mediaItemCollection {
if (mediaItemCollection) {
[_musicPlayer setQueueWithItemCollection: mediaItemCollection];
[_musicPlayer play];
}
[self dismissViewControllerAnimated:YES completion:nil];
}
This all seems fairly straightforward to me, I've got no errors or warnings, and I know that the Media Picker and Music Player are working correctly because the correct songs start playing, it's just out of the wrong speaker. Could there be a "play media using this AudioSession" method or something? Or is there a way to check what audio session category is currently active, to confirm that nothing could have switched it back or something? Is there a way to emphatically tell the code to USE the receiver, rather than relying on the default to do so? I feel like I'm on the one-yard line, I just need to cross that final bit...
EDIT: I just thought of a theory, wherein it's something about the iPod Music Player that doesn't want to play out of the receiver. My reasoning: it is possible to set a song to start playing through the official iPod app and then seamlessly adjust it (pause, skip, etc) through the app I'm developing. The continuous playback from one app to the next made me think that maybe the iPod Music Player has its own audio route settings, or maybe it doesn't stop to check the settings in the new app? Does anyone who knows what they're talking about think it could it be something like that?
Was struggling with this for a while too. Maybe this would help someone later.You can also use the newer methods of overriding ports. Many of the methods in your sample code are actually deprecated.
So if you have your AudioSession sharedInstance by getting,
NSError *error = nil;
AVAudioSession *session = [AVAudioSession sharedInstance];
[session setCategory:AVAudioSessionCategoryPlayAndRecord error:&error];
[session setActive: YES error:nil];
The session category has to be AVAudioSessionCategoryPlayAndRecord
You can get the current output by checking this value.
AVAudioSessionPortDescription *routePort = session.currentRoute.outputs.firstObject;
NSString *portType = routePort.portType;
And now depending on the port you want to send it to, simply toggle the output using
if ([portType isEqualToString:#"Receiver"]) {
[session overrideOutputAudioPort:AVAudioSessionPortOverrideSpeaker error:&error];
} else {
[session overrideOutputAudioPort:AVAudioSessionPortOverrideNone error:&error];
}
This should be a quick way to toggle the outputs to the speaker phone and receiver.
You have to initialise your audio session first.
Using the C API
AudioSessionInitialize (NULL, NULL, NULL, NULL);
In iOS6 you can use AVAudioSession methods instead (you will need to import the AVFoundation framework to use AVAudioSession):
Initialization using AVAudioSession
self.audioSession = [AVAudioSession sharedInstance];
Setting the audioSession category using AVAudioSession
[self.audioSession setCategory:AVAudioSessionCategoryPlayAndRecord
error:nil];
For further research, if you want better search terms, here are the full names of the constants for the speakers:
const CFStringRef kAudioSessionOutputRoute_BuiltInReceiver;
const CFStringRef kAudioSessionOutputRoute_BuiltInSpeaker;
see apple's docs here
But the real mystery is why you are having any trouble routing to the receiver. It's the default behaviour for the playAndRecord category. Apple's documentation of kAudioSessionOverrideAudioRoute_None:
"Specifies, for the kAudioSessionCategory_PlayAndRecord category, that output audio should go to the receiver. This is the default output audio route for this category."
update
In your updated question you reveal that you are using the MPMusicPlayerController class. This class invokes the global music player (the same player used in the Music app). This music player is separate from your app, and so doesn't share the same audio session as your app's audioSession. Any properties you set on your app's audioSession will be ignored by the MPMusicPlayerController.
If you want control over your app's audio behaviour, you need to use an audio framework internal to your app. This would be AVAudioRecorder / AVAudioPlayer or Core Audio (Audio Queues, Audio Units or OpenAL). Whichever method you use, the audio session can be controlled either via AVAudioSession properties or via the Core Audio API. Core Audio gives you more fine-grained control, but with each new release of iOS more of it is ported over to AVFoundation, so start with that.
Also remember that the audio session provides a way for you to describe the intended behaviour of your app's audio in relation to the total iOS environment, but it will not hand you total control. Apple takes care to ensure that the user's expectations of their device's audio behaviour remain consistent between apps, and when one app needs to interrupt another's audio stream.
update 2
In your edit you allude to the possibility of audio sessions checking other app's audio session settings. That does not happen1. The idea is that each app sets it's preferences for it's own audio behaviour using it's self-contained audio session. The operating system arbitrates between conflicting audio requirements when more than one app competes for an unshareable resource, such as the internal microphone or one of the speakers, and will usually decide in favour of that behaviour which is most likely to meet the user's expectations of the device as a whole.
The MPMusicPlayerController class is slightly unusual in that it gives you the ability for one app to have some degree of control over another. In this case, your app is not playing the audio, it is sending a request to the Music Player to play audio on your behalf. Your control is limited by the extent of the MPMusicPlayerController API. For more control, your app will have to provide it's own implementation of audio playback.
In your comment you wonder:
Could there be a way to pull an MPMediaItem from the MPMusicPlayerController and then play them through the app-specific audio session, or anything like that?
That's a (big) subject for a new question. Here is a good starting read (from Chris Adamson's blog) From iPod Library to PCM Samples in Far Fewer Steps Than Were Previously Necessary - it's the sequel to From iphone media library to pcm samples in dozens of confounding and potentially lossy steps - that should give you a sense to the complexity you will face. This may have got easier since iOS6 but I wouldn't be so sure!
1 there is an otherAudioPlaying read-only BOOL property in ios6, but that's about it
Swift 3.0 Code
func provider(_ provider: CXProvider, didActivate audioSession: AVAudioSession) {
let routePort: AVAudioSessionPortDescription? = obsession. current Route. outputs. first
let portType: String? = routePort?.portType
if (portType == "Receiver") {
try? audioSession.overrideOutputAudioPort(.speaker)
}
else {
try? audioSession.overrideOutputAudioPort(.none)
}
swift 5.0
func activateProximitySensor(isOn: Bool) {
let device = UIDevice.current
device.isProximityMonitoringEnabled = isOn
if isOn {
NotificationCenter.default.addObserver(self, selector: #selector(proximityStateDidChange), name: UIDevice.proximityStateDidChangeNotification, object: device)
let session = AVAudioSession.sharedInstance()
do{
try session.setCategory(.playAndRecord)
try session.setActive(true)
try session.overrideOutputAudioPort(AVAudioSession.PortOverride.speaker)
} catch {
print ("\(#file) - \(#function) error: \(error.localizedDescription)")
}
} else {
NotificationCenter.default.removeObserver(self, name: UIDevice.proximityStateDidChangeNotification, object: device)
}
}
#objc func proximityStateDidChange(notification: NSNotification) {
if let device = notification.object as? UIDevice {
print(device)
let session = AVAudioSession.sharedInstance()
do{
let routePort: AVAudioSessionPortDescription? = session.currentRoute.outputs.first
let portType = routePort?.portType
if let type = portType, type.rawValue == "Receiver" {
try session.overrideOutputAudioPort(AVAudioSession.PortOverride.speaker)
} else {
try session.overrideOutputAudioPort(AVAudioSession.PortOverride.none)
}
} catch {
print ("\(#file) - \(#function) error: \(error.localizedDescription)")
}
}
}
I'm aware that this is a question already asked, I've found possible duplicates:
Detecting if headphones are plugged into iPhone
headphone plug-in plug-out event when audio route doesn't change - iOS
Detect if headphones (not microphone) are plugged in to an iOS device
...and more info on the WWW. But I've tried out every solution given and everytime I have problem, probably because they are old threads and are referring to iOS 4.
How can I detect it on iOS 5.0?
Thanks
If you're okay with an iOS 6-only solution, Apple added several new AVAudioSession properties that let you detect audio routes in just a few lines (and without the use of C).
Use this method to check for headphones (or adjust it to check for other outputs - "Speaker", "Headset", etc.):
- (BOOL)isHeadsetPluggedIn
{
// Get array of current audio outputs (there should only be one)
NSArray *outputs = [[AVAudioSession sharedInstance] currentRoute].outputs;
NSString *portName = [[outputs objectAtIndex:0] portName];
if ([portName isEqualToString:#"Headphones"]) {
return YES;
}
return NO;
}
If you want to respond to audio route changes passively, you can do this with the new NSNotification, AVAudioSessionRouteChangeNotification. Unfortunately, this notification doesn't tell you what the new route is, just the previous route that it switched from. But, you can just call some variation of the method above to get the current route.
Wes seems to have a great solution. Alas it is not international-proof. This code only works for the English language. In Dutch, for instance, the headset is called 'Koptelefoon' and
*portName
contains indeed 'Koptelefoon' which makes the test fail.
This will do the job internationally correct:
if ([portDescription.portType isEqualToString:AVAudioSessionPortHeadphones])
;