iOS AVPlayer slow rebuffering after connection loss - ios

I'm building a music streaming app using AVPlayer.
Everything is working fine, music keeps playing in the background, etc.
My problem is when I simulate connection loss on the phone (switch cellular data off, wait for the stream to stop and then switch back) it will take about 2 mins for the app to fill the buffer even if there's a 3G network present (I can surf the web meanwhile).
Everything is working in simulator, but not on device.
If I wait 2 mins I'll get a proper playbackLikelyToKeepUp notification, and from that on everything is fine, but that rebuffering should be just a few seconds. It's ok when I simulate low bandwidth by turning off bandwidth control on my router, but when I simulate carrier change by switching off cellular data and switch it back its that long.
I'm calling beginInterruption on "playbackBufferEmpty" and call endInterruption on "playbackLikelyToKeepUp". The main problem is "playbackLikelyToKeepUp" arrives way too late.
- (void)beginInterruption {
self.backgroundTaskIdentifier = [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:nil];
}
- (void)endInterruptionWithFlags:(NSUInteger)flags {
[[UIApplication sharedApplication] endBackgroundTask:self.backgroundTaskIdentifier];
self.backgroundTaskIdentifier = UIBackgroundTaskInvalid;
if(self.interrupted) [self play];
self.interrupted = NO;
}
Any ideas? I've spent my whole day with this issue, googled everything but I'm stuck.
Thanks in advance.

I suffered the same situation months ago, my conclusion is "playbackLikelyToKeepUp is not reliable".
My solution is checked the buffered TimeRange manually.
FYI, I made a AVPlayer class for remote media playback - HysteriaPlayer.
You can use it directly, or look up the .m file.
Hope this helps.

Related

Spotify audio player stops randomly after few seconds

Sometimes when I play sound file, it stops randomly after few seconds."didChangePlaybackStatus" method of SPTAudioStreamingPlaybackDelegate gets called after fews seconds. The issue is not so frequent but can be reproduced after few tries. Need help.
- (void)audioStreaming:(SPTAudioStreamingController *)audioStreaming didChangePlaybackStatus:(BOOL)isPlaying {
_playerController.nowPlaying = self.isPlaying = isPlaying;
}
-- Here is the screenshot for the call trace, when audio stops automatically.
Please make sure your are not using same spotify account more than one place.
As in my case I was using my account in two devices (android+ios) and was getting same issue.

iOS text-to-speech in background

I am having an intermittent (aargh!) problem playing Text-to-Speech in the background, triggered from Apple Watch. I have properly set up the background mode, the AVSession category, and the WatchKitExtensionRequest handler. (See below.) I had this working before, and can't figure out what changed. (Could it be iOS 9 has issues? "Before" means, among other things, iOS 8.)
The problem is this: when the app gets the request from the Watch and the app is either in the background or the phone is sleeping (locked), the speech sometimes plays right away, and other times doesn't play until the app is brought to the foreground. The OS seems to be sometimes queuing the audio, and sometimes not. I can't find any common thread between success and failure cases. I can verify with logging that the call to speakUtterance() is being made in all situations. But its behavior varies, apparently randomly. The only clue is that it might be the case that the longer the app is in the background, the less likely it is to speak right away.
This is making me pull my hair out. Suggestions welcome.
In info.plist:
Required background modes: App plays audio or streams audio/video using AirPlay
In AppDelegate.application:didFinishLaunching:withOptions():
do {
try AVAudioSession.sharedInstance().setCategory(
AVAudioSessionCategoryPlayback,
withOptions:.DuckOthers
)
try AVAudioSession.sharedInstance().setActive(true)
} catch let error as NSError {
// etc...
}
In AppDelegate.application:handleWatchKitExtensionRequest...():
var bgTaskId:UIBackgroundTaskIdentifier = 0
bgTaskId = application.beginBackgroundTaskWithName(
"Prose WKE handler",
expirationHandler: {
application.endBackgroundTask(bgTaskId)
}
)
//... Post notification to call Text-to-Speech
application.endBackgroundTask(bgTaskId)
Here's a workaround: play a second snippet of sound (I used a half-second of silence), using AVAudioPlayer, right after the call to speakUtterance(), This seems to "jog the pipeline".

Audio interruption when iOS application is recording in background

My iPad sound application (iOS 7.1) is able to record while in background. Everything is ok as far as recording is not interrupted while in background. For example if one's has the (stupid?) idea to start listening music while recording something.
I tried to manage this interruption in different ways, with no success. The problem is that the
- (void)audioRecorderEndInterruption:(AVAudioPlayer *)p withOptions:(NSUInteger)flags
is never fired when application was in background as the interruption occurred. I then tried, in another solution, to implement the AVAudioSessionInterruptionNotification and a handleInterruption: method as
- (void) viewDidAppear:(BOOL)animated
{
......
AVAudioSession *session=[AVAudioSession sharedInstance];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(handleInterruption:)
name:AVAudioSessionInterruptionNotification
object:session];
.......
}
// interruption handling
- (void)handleInterruption:(NSNotification *)notification
{
try {
UInt8 theInterruptionType = [[notification.userInfo valueForKey:AVAudioSessionInterruptionTypeKey] intValue];
NSLog(#"Session interrupted > --- %s ---\n", theInterruptionType == AVAudioSessionInterruptionTypeBegan ? "Begin Interruption" : "End Interruption");
.... MANAGE interruption begin
interruptionBeganWhileInBackgroundMode = TRUE;
}
if (theInterruptionType == AVAudioSessionInterruptionTypeEnded) {
.... MANAGE interruption end
}
} catch (CAXException e) {
char buf[256];
fprintf(stderr, "Error: %s (%s)\n", e.mOperation, e.FormatError(buf));
}
}
In this case the handleInterruption: is fired when interruption begins, but it is not when interruption ends (shoulld be fired with theInterruptionType set to AVAudioSessionInterruptionTypeEnded)
To circumvent this problem, I decided to set a flag (interruptionBeganWhileInBackgroundMode) when interruption begins to get the application informed that an interruption has occurred when coming foreground. So that I can manage the end of interruption.
It may seem clever, but it is not! Here is why...
I tried two implementations.
Solution 1. Put a [recorder pause] in handleInterruption: when interruption begins, and manage a [recorder record] in the comingForeground: method when the interruption flag is set.
In this situation, the recording is going on immediately when application comes back to foreground, BUT instead of resuming, the recorder erase the file and restart a new recording, so that everything recorded before interruption is lost.
Solution 2. Put a [recorder stop] in handleInterruption: when interruption begins, to save the file, to be sure to preserve the recorded data. This recording is saved, BUT when application is coming foreground, it stalls for about ten seconds before the user can interact again, as if there was a process (the file saving?) that keep the UI frozen.
Last point: I have exactly the same problems in iPhone version of this application: when application is foreground and a phone call occurs, everything goes OK. But when a phone call occurs as my application is background I see the same bad behaviour as in iPad's version.
I notice that Apple's Voice Memo app in iOS7 correctly manage these background interruptions (it stops and saves the recording) despite it displays a 00:00:00 file length when coming foreground. The iTalk application manages it perfectly, automatically resuming recording when coming foreground.
Did anybody find a workaround for the audio interruption management for backgrounded recording applications? I found plenty of people looking for that in many developer websites, but no answer... Thanks!
I have been going through the same issue myself. It seems as if there is a bug in the iOS7 AVAudioRecorder in how it deals with interrupts. Instead of pausing as I believe the documentation says that is should, it closes the file. I have not been able to figure out what is stalling the app when it comes back to the foreground. In my case, I would see AVAudioRecorder finish (with the success flag set to NO), after 10 seconds.
I ended up rewriting the audio recorder using Audio Queues. I found some sample code here (git#github.com:vecter/Audio-Queue-Services-Example.git) that helped with setting it up in an Objective-C environment and the Apple SpeakHere demo has some code to handle the interrupt notifications.
Essentially, I am stopping the recording on interrupt began and opening an alert for the user to save the file. This alert is deferred until UIApplicationDidBecomeActiveNotification is passed if the interrupt started while the app was in the background.
One other thing to note, there seems to be a minor bug in Audio Queues that the AudioQueueStart method will return -50 sometimes. If you add
AudioSessionInitialize(NULL, NULL,nil,(__bridge void *)(self));
UInt32 sessionCategory = kAudioSessionCategory_PlayAndRecord;
AudioSessionSetProperty(kAudioSessionProperty_AudioCategory,
sizeof(sessionCategory),
&sessionCategory
);
AudioSessionSetActive(true);
Before any AudioQueue methods, the error goes away. These methods are marked as deprecated but seem to be necessary.
Don't know / think this is going to be relevant to the original author of the topic, but here is my experience with it:
I ended up here because of the AVAudioSessionInterruptionNotification thing; the .began flavour came as expected, but the .ended one did not.
In my case, it happened because I was using two AVPlayer instances: one to play music, and the other one to play silence while the first struggled to start streaming a new track (otherwise iOS would suspend my app while in background, if next track loading did not happen fast enough).
Turns out it's not the brightest solution, and it somehow messes up the notification system. Giving up the second AVPlayer (the silence playing one) resulted in .ended being triggered as expected.
Of course, I found the answer / solution for the notification problem, but I'm now left with the old one... :-)

Videos are downloaded up to 10 min only when app goes to background mode in iOS-7

i am trying download load the large videos(400 mb) into background cont.... until end of the video in iOS-7 using Xcode-5 . But After 10 or 5 min downloading is stop .
i wrote the code like below and i set the "background fetch mode is YES". Is There any wrong with my code.
Ref 1: https://developer.apple.com/library/ios/documentation/iphone/conceptual/iphoneosprogrammingguide/ManagingYourApplicationsFlow/ManagingYourApplicationsFlow.html
Ref 2:
Question : How can i kept alive the my URL request upto my videos are downloaded in background mode?
Thanks in Advence.
- (void)applicationDidEnterBackground:(UIApplication *)application
{
UIApplication *app = [UIApplication sharedApplication];
UIBackgroundTaskIdentifier m_backgroundTaskId;
m_backgroundTaskId = [[UIApplication sharedApplication]
beginBackgroundTaskWithExpirationHandler:^(void) {
m_isWentBackground = YES;
[m_dataController saveUnfineshedDownoadsToFile];
[[UIApplication sharedApplication]
endBackgroundTask:m_backgroundTaskId];
m_backgroundTaskId = UIBackgroundTaskInvalid;
}];
}
You are doing it wrong, the beginBackgroundTaskWithExpirationHandler will give you up to 10 extra minutes to download, but if you want real background download, you have to look into Background Transfer Service
You have 2 tutorials:
One from techtopia
Other from tuts plus
Background processing is only allowed to a maximum of 10 minutes in ios unless your app is of one of the following types..
Apps that play audible content to the user while in the background, such as a music player app
Apps that keep users informed of their location at all times, such as a navigation app
Apps that support Voice over Internet Protocol (VoIP)
Newsstand apps that need to download and process new content
Apps that receive regular updates from external accessories
Refer the following for more info..
http://docs.xamarin.com/guides/cross-platform/application_fundamentals/backgrounding/part_3_ios_backgrounding_techniques/ios_backgrounding_with_tasks/
https://stackoverflow.com/a/9738707/919545
The beginBackgroundTaskWithExpirationHandler of UIApplication is supposed to be used a "task finisher". There is nothing wrong with your code, but it is the purpose of this code that is the problem.
This operation will be kept alive for a maximum of 10 min or so, and it is the operating system which decides for how long the task will be operational. If you are downloading a 400mb video, it is not what you need.
You should consider another way to do this task - Which is not in a background operation.
A background operation, by Apple own definition can not last more than 10 minutes.
Perhaps, performing queued background operations, that will gradually append data, until you will have the complete video? Or doing this operation while app is not in background in another thread?
A 400mb video does not sounds like something a mobile device should do, as default.

Running iOS app in the background forever

I have a requirement where my app connects to a country channel (USA) and starts playing records from the channel. This is basically a channel which is run by users, the users upload their records to channel and they are played one by one. The user who connects to channel they start listening to channel.
The server sends the iOS app the URLs for the record that needs to be played via sockets, the iOS app creates AVQueuePlayer to play the URL's (using AVPlayerItems) one by one.
If I keep app in background when the channel is full of records for almost 1 day or so, the app keep running and keep playing all the records one by one. I know that AVQueuePlayer takes care of running the app all the time without killing as it receives new player items to play.
But if there are no records in channel and if user connects to channel, then app doesn't play the records in background if the idle time of the app exceeds 10 minutes.
I have written code with background task identifier which keeps my socket connect open so that new record URLs can be received all the time.
I see some of the crash reports in my device which says "AppName(my app) has active assertions beyond permitted time"
So can I know what wrong is going on here.
I am posting the background task code as well
- (void)keepBroadcastPersistentConnection {
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
if(self._bgTaskIdentifier)
self._bgTaskIdentifier = UIBackgroundTaskInvalid;
self._bgTaskIdentifier = [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler: ^{
[[UIApplication sharedApplication] endBackgroundTask:self._bgTaskIdentifier];
self._bgTaskIdentifier = UIBackgroundTaskInvalid;
CGLog(#"========================================end bg task at time %#", [NSDate date]);
CGLog(#"Time taken by app to run in bg is %f seconds", [[NSDate date] timeIntervalSinceDate:self.date]);
}];
[[BroadcastSocketConnecter sharedSocketConnecter].socketIO sendHeartbeat]; // this keep the socket alive
self.date = [NSDate date];
CGLog(#"========================================begin bg task at time %#", self.date);
});
}
Thanks
From the audio session programming guide:
Why a Default Audio Session Usually Isn’t What You Want
Scenario 3. You write a streaming radio application that uses Audio
Queue Services for playback. While a user is listening, a phone call
arrives and stops your sound, as expected. The user chooses to ignore
the call and dismisses the alert. The user taps Play again to resume
the music stream, but nothing happens. To resume playback, the user
must quit your application and restart it.
To handle the interruption of an audio queue gracefully, implement
delegate methods or write an audio session callback function to allow
your application to continue playing automatically or to allow the
user to manually resume playing. See “Responding to Audio Session
Interruptions.”
Shortly, the solution would be to implement the AVAudioSessionDelegate protocol'a beginInterruption and endInterruption methods. However, the delegate property of the AvAudioSession class was deprecated in iOS6 and Notifications should be used instead. Namely, you are interested in the AVAudioSessionInterruptionNotification
Solution. According to this story if the playback stops, then you should explicitly activate the audio session again to prevent your app from being terminated.
Below is the source for the delegate implementation but the logic doesn't change much with the notifications so I feel it's still a good source for info.
- (void) beginInterruption {
if (playing) {
playing = NO;
interruptedWhilePlaying = YES;
[self updateUserInterface];
}
}
NSError *activationError = nil;
- (void) endInterruption {
if (interruptedWhilePlaying) {
BOOL success = [[AVAudioSession sharedInstance] setActive: YES error: &activationError];
if (!success) { /* handle the error in activationError */ }
[player play];
playing = YES;
interruptedWhilePlaying = NO;
[self updateUserInterface];
}
}
Old response which is still valid but not an elegant solution
You cannot start playing audio in the background. This answer explains what I mentioned in my comment above: https://stackoverflow.com/a/16568437/768935 Doing tricks with the AudioSession does not seem to have an effect on this policy.
As a solution, you need to keep playing audio. If there is no item in the queue, then insert the "silence" audio track. However, I have my doubts that the app with this trick will be admitted in the App Store. It may be better to inform the user that audio playback will be resumed on if the app is started again.

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