Question

I am developing an app that have to stream live audio (from a m3u distant file) and I am looking for a way to check if the live-stream is “On air” or “Off air”. The audio player uses AVPlayer.

I made my homeworks, but did’nt find anything on that subject…

Thanks a lot…

Answer 1

When you are using a AVPlayer and AVPlayerItem, add observers like this method below:

-(void) addMediaObservers {
    [_playerItem addObserver:self forKeyPath:@"player_buffer_empty" options:0 context:@"player_buffer_empty"];
    [_playerItem addObserver:self forKeyPath:@"item_status" options:0 context:@"item_status"];

    [_player addObserver:self forKeyPath:@"player_status" options:0 context:@"player_status"];
}

Please don’t forget to remove these observers when stops the streaming, or in the dealloc method.

- (void)stop
{
    [_playerItem removeObserver:self forKeyPath:@"player_buffer_empty"];
    [_playerItem removeObserver:self forKeyPath:@"item_status"];
    [_player removeObserver:self forKeyPath:@"player_status"];
}

At the methods below you will manage the audio streaming:

- (void)observeValueForKeyPath:(NSString *)keyPath
                  ofObject:(id)object
                    change:(NSDictionary *)change
                   context:(void *)context
{
    if (context && ([context isEqualToString:@"item_status"] || [context isEqualToString:@"player_status"] || [context isEqualToString:@"player_buffer_empty"]))
    {
        [self checkStatus];
    }
}

- (void)checkStatus
{
    AVPlayerItemStatus ps = _playerItem && _playerItem.status ? _playerItem.status : AVPlayerItemStatusUnknown;
    AVPlayerStatus s = _player && _player.status ? _player.status : AVPlayerStatusUnknown;

    BOOL isReady = ps == AVPlayerItemStatusReadyToPlay && s == AVPlayerStatusReadyToPlay;

    if (_isPlaying) {
        if (!_isLoading && _player && _playerItem && _playerItem.playbackBufferEmpty) {
            _isLoading = YES;
            [self performSelector:@selector(unpause) withObject:nil afterDelay:20];
        }
        if (!isReady)
            [self stop];
    } else {
        if (isReady)
            [self play];
    }
}

All the variables used in the methods not declared in the scope of the method are global.
I hope this helps!