I am developing an iPhone app that translates voice to text.
The component for the Transcribe is third-party.
Until now everything worked just fine.
Today I tried playing a sound (.wav file) after making the Transcription and noticed that I cannot play anything (by AVAudio or system sound). After debugging I found out that this is happening after initing the third-party component; so I think that the component is not releasing something that belongs to the system audio.
My question is : Is there a way to force the iPhone play the sound that I want?
Have you tried setting AVAudioSession category?
NSError *err = nil;
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:&err];
Maybe other category will work, for example AVAudioSessionCategoryPlayAndRecord
The best way IMO is to save AVAudioSession state (its category, for example) before using your third-party component and restore state afterwards.
Related
I have a codebase which plays audio and video perfectly. I have converted that into a small framework and started using it as a part of another code. When i do this, there is no audio output.... I am unable to hear any audio output while it is being played. All the Audio player delegate methods are being called but there is no sound. The same is happening with Videos as well. All the videos are being played with out sound. Its like watching a silent movie.... Any ideas? I am using AVAudioPlayer for playing audio files and MPMoviePlayerController for playing videos.
edit : This happens only on device. It works all fine in simulator
Just came across this post, I was doing the same thing, and actually AVAduioSession is needed to play audio thru speaker/headset. So having AVAudioSession is a must.
//REALLY NEED THIS LINE FOR MUSIC TO PLAY TO SPEAKER
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:nil];
and for background playing, add these 2 lines and change setting in plist to allow background mode
[[AVAudioSession sharedInstance] setActive: YES error: nil];
[[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
So stupid of me.... The problem was with the volume button on iPad. The volume button in iPad with iOS 5 has some weird bug. It does not update itself when we toggle the button between screen lock and audio output. I guess this is bug from apple and filed a bug. Hope they solve this in their next update.
I got a need to stop (or mute at least) music/sound that is played in iPhone.
Important: I want my app will do that it even if is in background-state!
I'm using:
[[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategorySoloAmbient error:nil]];
[[AVAudioSession sharedInstance] setActive: YES];
The issue is that everything is being stopped, even streaming music from some other app, but only if app is in FOREGROUND. As wrote before, I want it to be working also in BACKGROUND.
I did simple research and realized it's somehow possible, these apps prove:
App Store - Streaming Music Timer or
App Store - Music Sleep Timer
I guess my solution with SoloAmbient can be not so perfect and it may be a wrong way.
Does anybody know how could I stop/sleep/pause/mute global music even if app will be in background state?
These apps I pointed out are doing basically this thing...
You need to enable the audio background mode.
Add the Required Background Modes key to your app's Info.plist and add the App Plays Audio key to it.
See this tutorial for more.
EDIT Also, you probably want the AVAudioSessionCategoryPlayback category, not AVAudioSessionCategorySoloAmbient
I have an App that does the pretty standard operation:
It plays audio (streamed or in filesystem) when the app is in 1) Foreground mode, 2) Screen locked state 3)Background mode.
This was working fine in all iOS prior to iOS5.
I have been using MPMoviePlayerController (Because it can play streamed and local file system audio)
I have the following setup:
info.plist has Background Mode set to "Audio"
I have Audiosession setup as shown at http://developer.apple.com/library/ios/#qa/qa1668/_index.html
NSError *activationError = nil;
AVAudioSession *mySession = [AVAudioSession sharedInstance];
[mySession setCategory: AVAudioSessionCategoryPlayback error: &activationError];
if (activationError) { /* handle the error condition */ }
[mySession setActive: YES error: &activationError];
if (activationError) { /* handle the error condition */ }
I have background timer enabled that gets stopped at the end of audio playback
UIBackgroundTaskIdentifier newId = [[UIApplication sharedApplication]
beginBackgroundTaskWithExpirationHandler:NULL];
I have the Moveplayer's useApplicationAudioSession = NO
I have subscribed to the following events to detect and handle various playback state and to start a new audio file at the end of current file.
MPMoviePlayerLoadStateDidChangeNotification
MPMoviePlayerPlaybackDidFinishNotification
MPMoviePlayerPlaybackStateDidChangeNotification
MPMoviePlayerNowPlayingMovieDidChangeNotification
Problem:
With this the audio starts to play and when the application is put to background state or if the phone is locked, the audio continues to play. But, after when I start another audio file,
I start getting PlaybackDidFinishNotification immediately with the state set to Playback ended (But the file was never played)
The same code plays audio files in foreground mode (After the current audio file ends, the next file is started without any problem)
Is there anything new in iOS5 I should be doing to get this to work? I read through the MPMoviePlayerController class reference and I couldn't see anything specific for iOS5.
Thanks in advance.
Finally figured out the issue. This is solved in this post in apple dev forums (needs login to see). That post was applicable to AVPlayer but also fixes the problem with MPMoviePlayerController as well.
Basically, this is an excerpt from that post:
your app must support remote control events! These are the audio
controller interface prex/nex/play/pause on the left of the multitask
switcher taskbar (not sure about the proper name of the thing). You
to this ensuring your view becomes First Controller and then calling
> [[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
in viewDidLoad. Once you do this, your Player will no longer return
NO!!
My situation was different and I'm only answering here (and in the other SO question) to help future searchers on this error message. This does not answer the original question.
My app plays a sound OR a song but when I first coded it could play both. And in testing I always tested with a song. I played the song in the usual way:
self.musicQuery = [MPMediaQuery songsQuery];
[_musicQuery addFilterPredicate:[MPMediaPropertyPredicate predicateWithValue:selectedSongID forProperty:MPMediaItemPropertyPersistentID comparisonType:MPMediaPredicateComparisonEqualTo]];
[_musicQuery setGroupingType:MPMediaGroupingTitle];
[_myPlayer setQueueWithQuery:_musicQuery];
[_myPlayer play];
Weeks passed and I started testing with the sound, played with AVAudioPlayer. My app started freezing for 5 seconds and I'd get the MediaPlayer: Message playbackState timed out message in the Console.
It turns out that passing a query that was empty was causing the freeze and the message. Changing my app's logic to only play a song when there was a song to play fixed it.
I have been trying to do this for a few days now using AVFoundation as well as trying to use MPMoviePlayerViewController. The closest I can get is allowing one to play at a time. I would like to think that this is possible because of Facetime. However, I know this is a little different because there is no separate video file.
Any ideas would help, and thanks.
I'm not sure where this is documented, but to get AVCaptureVideoPreviewLayer and MPMoviePlayerViewController to play together at the same time you need to set a mixable audio session category first.
Here's one way to do that:
AVAudioSession* session = [AVAudioSession sharedInstance];
[session setCategory:AVAudioSessionCategoryPlayback error:nil];
UInt32 mixable = 1;
AudioSessionSetProperty(kAudioSessionProperty_OverrideCategoryMixWithOthers, sizeof(mixable), &mixable);
[session setActive:YES error:nil];
See the Audio Session Programming Guide and Audio Session Cookbook for more info.
Have you tried to play video on one thread and recording video on another? That would allow both of them to run while maintaining their separation.
How to check whether microphone is muted before recording audio in iPhone?
Actually, you don't have to. You have to "warn" AVAudioSession that you are going to record a bit of Audio. Doing so, even if you are muted (on the IPhone, I Have not tested this with any external device) you will be able to record your audio... here is the piece of code that does that:
[[AVAudioSession sharedInstance]
setCategory: AVAudioSessionCategoryRecord
error: &error];
it even records with a higher volume.
Best of luck...