iPhone PlayAndRecord silences all system audio? - iphone

In my iPhone app I am trying to record audio and play iPod music at the same time, so I set the audio session category to kAudioSessionCategory_PlayAndRecord. But when I set this, all system audio (including vibrate) doesn't work anymore, although the iPod audio still does work. Does anyone know if this is a bug in the SDK or something, or how to get around it? Please help!
Thanks in advance!

Looking at the documentation for kAudioSessionOverrideAudioRoute tells us that the default for the category PlayAndRecord is to route the audio to the receiver (the speaker used when you're talking on the phone). Is it possible that all the audio is being routed to that and you just can't hear without putting your ear there?
If you want to change where the audio is going you need to call AudioSessionSetProperty, and pass it the constant specifying where you want the audio to go. These constants are
kAudioSessionOverrideAudioRoute_None, which specifies that you wish the audio to be routed to the receiver (as it is now), or
kAudioSessionOverrideAudioRoute_Speaker, which specifies that audio should be routed to the speaker at the bottom of the phone
UInt32 routeVar = kAudioSessionOverrideAudioRoute_Speaker;
AudioSessionSetProperty(kAudioSessionProperty_OverrideAudioRoute, sizeof(routeVar), &routeVar);

Related

Recording from radio streaming xcode 4

I'm building an iPhone app which play some radio over internet ..
I want to make user able to record audio from my application to the radio channel he wants ..
what framework I must use .. and what code for implementation please ?
all Regards
Unfortunately, there is no way to directly capture from the "audio bus". You can either capture the audio via the internal microphone or headset microphone, but that's it. If you are rendering the audio, you could obviously also write that audio out to a file as well at the same time. That's pretty much your only option.

How can I record currently playing audio on the iPhone?

I'd like to record what the iPhone is currently outputting. So I'm thinking about recording audio from Apps like Music (iPod), Skype, any Radio Streaming App, Phone, Instacast... I don't want to record my own audio or the mic input.
Is there an official way to do this? How do I do it? It seems like AVAudioRecorder does not allow this, can somebody confirm?
Officially you can't. The audio stream belongs to the app playing it ,and iOS.
The Sandbox paradigm means that a resource owned by your App can't be used by another App. Resource here means Audio/Video stream or file. Exceptions are when a mediator like Document interaction controller are used.
If you want to do this you'd have to start with deducing AVFoundation's private methods and find out if theres a way there. Needless to say this it wouldn't be saleable on the App store and will probably only be possible on a jailbreak.
Good Luck.
TLDR;
This is only feasible only from time to time, as it's a time expensive process.
You can record the screen while listening your songs on Spotify, Music or whatever music application.
This will generate a video on your Photos application. That video can be converted on MP3 from your computer.
Actually, this is not true. The screen recordings will not actually have the audio from Apple Music at all, as it blocks it. Discord also uses this pipe as well, so you cannot record Discord audio either this way.

Using MediaPlayer and AVFoundation Framework simultaniously in XCode

I'm an inexperienced XCode use and programmer in general so keep that in mind. I'm trying to use the microphone on the iPhone while at the same time allowing the user to play audio while using the "iPod music picker", but when the user selects music and plays it the recorder stops working? I have no idea what is going on here? Also, on a side note, how do you implement forward and back iPod buttons?
Thanks so much!
Sounds like this is an Audio Session issue - you're probably in a mode where you can either play or record, but not both at the same time.
Check out the Audio Session Programming Guide which should explain how to configure your session.
AVAudioSessionCategoryPlayAndRecord — Use this category for an application that inputs and outputs audio. The input and output need not occur simultaneously, but can if needed. This is the category to use for audio chat applications.
AVAudioSessionCategoryAmbient - This category allows audio from the iPod, Safari, and other built-in applications to play while your application is playing audio. You could, for example, use this category for an application that provides a virtual musical instrument that a user plays along to iPod audio.

iPhone recording audio

I'm currently working on a project where it is necessary to record sound being played by the iPhone. By this, I mean recording sound being played in the background like a sound clip or whatever, NOT using the built-in microphone.
Can this be done? I am currently experimenting with the AVAudioRecorder but this only captures sound with the built-in microphone.
Any help would be appreciated!
This is possible only when using only the Audio Unit RemoteIO API or only the Audio Queue API with uncompressed raw audio, and with no background audio mixed in. Then you have full access to the audio samples, and can queue them up to be saved in a file.
It is not possible to record sound output of the device itself using any of the other public audio APIs.
Just to elaborate on hotpaw2's answer, if you are responsible for generating the sound then you can retrieve it. But if you are not, you cannot. You only have any control over sounds in your process. yes, you can choose to stifle sounds coming from different processes. but you can't actually get the data for these sounds or process them in any way.

Route audio to earpiece?

Is it possible to route audio such as a local mp3 file to play through the iPhone earpiece instead of speakerphone?
It is possible, yet a bit complicated as it appears. You might want to check the paragraph Audio Session Category Route Overrides in the Audio Sessions Services Reference, to get into the matter.