How to switch among alternate audio streams using AVPlayer - ios

I have a test application that uses AVPlayer to play video specified by an m3u8 HLS playlist. The playlist specifies several alternate audio streams, similar to the "Listing 10" sample playlist provided by Apple found here: http://developer.apple.com/library/ios/#technotes/tn2288/_index.html#//apple_ref/doc/uid/DTS40012238-CH1-ALTERNATE_MEDIA The app needs to be able to switch among the alternate audio streams while the video is playing. For example, the app should be able to switch among the English, French, and Spanish audio streams by the user tapping buttons in the app while the video is playing.
Which AVFoundation classes and methods would be used by the AVPlayer and its related objects to switch among the audio streams that are specified in the m3u8 playlist? I have looked at the AVFoundation class documentation but do not see how to do this.
A link to some sample code that shows how to do this would be great. I have been searching the web for this information without success. Thanks for any help with this.

For m3u8 playback with AVPlayer, it looks like you cannot use an AVAsset to construct an AVPlayerItem. You need to construct an AVPlayerItem from the URI directly. Upon instantiating an AVPlayer with this AVPlayerItem, and then KVO listening on the property #"status", you will have an asset within the [[avPlayerInstance currentItem] asset] if the status is AVPlayerStatusReadyToPlay. This is described on page 20 of the AV Foundation Programming Guide.
To change audio to various alternates use:
AVMediaSelectionGroup *audioSelectionGroup = [[[avPlayerInstance currentItem] asset] mediaSelectionGroupForMediaCharacteristic: AVMediaCharacteristicAudible];
NSLog(#"audioSelectionGroup: %#", audioSelectionGroup);
// [audioSelectionGroup options] // Array of the options in the group above.
And the select AVMediaSelectionOption (the audio channel you want) with:
[[avPlayerInstance currentItem] selectMediaOption:avMediaSelectionOptionInstance] inMediaSelectionGroup: audioSelectionGroup];
The same will work for video.
This is described in the "Selection of audio and subtitle media according to language and other criteria" section of the AV Foundation Release Notes for IOS 5 (3rd section).

Related

Difference between AV Foundation framework and Media Player framework

Audio and video files can be played using AV Foundation framework and Media Player framework.
What is the better choice when I just want to play the media file?
With Media Player framework, we can access the iPod library, and can find and play audio-based media items synced from iTunes on the desktop.
With AVFoundation, we can examine, create, edit, or reencode media files.
When you want to much customization then it is better to use AVFoundation for example AVPlayer. You can totally customize player, audio, sessions etc. so, it is better to use AVPlayer instead of MPMoviePlayerController when lot's of customization requires.
MPMoviePlayerController are very easy to implements compare to AVPlayer.
MPMoviePlayerController:
You have to set controlStyle to MPMovieControlStyleNone, set up Timer because currentPlaybackTime is not KVO compliance
AVPlayer:
AVPlayer has no built in controls, but it has addPeriodicTimeObserverForInterval:queue:usingBlock: that makes handling the current time easily. The nicer thing about periodTimeObserver is that “The block is also invoked whenever time jumps and whenever playback starts or stops”
etc etc.
You can refer this document for more details and better understanding.
Hope this will help :)
Media Player framework:
This high-level framework provides easy access to a user’s iTunes library and support for playing tracks and playlists. Use this framework when you want to integrate audio into your app quickly and when you don’t need to control playback behavior.
AV Foundation:
AV Foundation is an Objective-C interface for managing the recording and playback of audio and video. Use this framework for recording audio and when you need fine-grained control over the audio playback process.
https://developer.apple.com/library/content/documentation/Miscellaneous/Conceptual/iPhoneOSTechOverview/MediaLayer/MediaLayer.html

ios Can I use MPMoviePlayerController to play .mp3 url

My app needs to play some music files, like .mp3. I would like to use MPMoviePlayerController because it has implemented all the UI stuff for me, i.e. I do not want to bother implementing progress slide bar and things like this.
I tested to use it to play a .mp3 file and it worked fine but I do not know if it is fine to use it to do this because its name says "movie player" and it seems it is supposed to play a movie. Would apple reject this? Thank you.
For playing audio from a file or memory, AVAudioPlayer is your best option but unfortunately it doesn't support a network stream while MPMoviePlayerController can
From documentation :
An instance of the AVAudioPlayer class, called an audio player,
provides playback of audio data from a file or memory.
Apple recommends that you use this class for audio playback unless you
are playing audio captured from a network stream or require very low
I/O latency.
For the Apple validation I don't think that your application can be rejected because you're using the Media Player Framework to play an audio file. In fact here they explicitly say that you can do just that:
Choose the right technology for your needs:
To play the audio items in a user’s iPod library, or to play local or
streamed movies, use the Media Player framework. Classes in this
framework automatically support sending audio and video to AirPlay
devices such as Apple TV.
Not sure about performance and memory issues though!
Best of luck.

How to create a music player for iPhone/iPad which can buffer and play songs from server?

I want to develop a music player for iPhone/iPad with the functionality:
-Buffer and Play MP3 songs from server(no downloading).
-Play.
-Pause.
-Stop.
-Adjust Volume(Slider).
-Song Status/ Playing time for Song(slider).
-Repeat Song.
-Shuffle Songs.
-In the center of the Music Player there must be eq like dancing bars with song etc.
I am using AVPlayer for this but it is giving me trouble with Adjust Volume,Stop,Song Timers etc. With AVPlayer only play/pause and buffering is working.
Even i have used AVAudioPlayer also and it was working fine with all the functionality i needed but with local files only, may be i don't know any method play songs from server in AVAudioPlayer.
Help me with any suggestions,examples,sample code or tutorial.
Playing an MP3 stream seems like it should be a straightforward task that the Cocoa APIs would handle easily.
see this post Live streaming

Muting an AVPlayer playing Http Live Streaming video

I was wondering if I could mute the sound of an AVPlayer playing a HTTP Live Streaming video?
I've already try several things, like the Apple method to set the volume of an AVPlayer explained here but it works only for local files... (cf. the note at the bottom of Apple documentation).
The similar method explained in this post does not working either.
Is there an solution? I really don't want to mute the sound of the device but only one video while other players could have their own audio (the user could balance audio between players).
Thanks in advance.
iOS 7.0 now provides support for muting the player using
[AVPlayer setVolume:(float)volume]
It also works for HTTP Live Streaming, my app is making extensive use of it.
According to the AVFoundation team, it is impossible to mute or disable a track of an HLS video.
You can mute the entire audio session using MPMusicPlayerController shared instance.
[[MPMusicPlayerController applicationMusicPlayer ]setVolume:0];

Playing a .mov file without UIWebView or MPMoviePlayer

I am trying to play a video file with the .mov extension. It is not playing the video in my MPMoviePlayerController. I need to play this type of file in my application. Is it possible to play a video file without using MPMoviePlayerController or UIWebView?
Please anyone suggest me in this issue.
Thanks in Advance
I've never used it directly before, but take a look at the AVPlayer Class Reference.
Under the "Overview", you'll see:
You use an AVPlayer object to implement controllers and user
interfaces for single- or multiple-item playback. The multiple-item
case supports advanced behaviors.
If you look at the AV Foundation Programming guide (linked here), you'll see Apple builds the Media Player upon AV foundation.

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