iOS 从 avplayer 获取音频时长

Question

我是 ios 的新手，我有一个包含在线音频播放器的应用程序。我需要获得音频的总持续时间。我已经尝试了很多，但所有代码都返回 NaN 或 0 持续时间。获取音频总持续时间的最佳方法是什么......？

我的代码

NSString *songUrl = @"http://9xmusiq.com/songs2/tamil/Kaatru%20Veliyidai/Azhagiye%20%5bStarmusiq.cc%5d.mp3"

AVURLAsset *asset = [AVURLAsset assetWithURL:[NSURL URLWithString:songUrl]];
AVPlayerItem *playerItem1 = [AVPlayerItem playerItemWithAsset:asset];
AVPlayer *player1 = [AVPlayer playerWithPlayerItem:playerItem1];
AVPlayerLayer *playerLayer1 = [AVPlayerLayer playerLayerWithPlayer:player1];
playerLayer1.videoGravity = AVLayerVideoGravityResizeAspectFill;
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.1 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
    playerLayer1.frame = self.view.frame;
});

[self.view.layer insertSublayer:playerLayer1 atIndex:1];
[player1 play];
[playerItem1 addObserver:self forKeyPath:@"status" options:0 context:nil];
[playerItem1 addObserver:self forKeyPath:@"playbackBufferEmpty" options:0 context:nil];


- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context{
if ([object isKindOfClass:[AVPlayerItem class]]){
    AVPlayerItem *item = (AVPlayerItem *)object;
    if ([keyPath isEqualToString:@"status"]){
        switch(item.status){
            case AVPlayerItemStatusFailed:
                NSLog(@"player item status failed");
                break;
            case AVPlayerItemStatusReadyToPlay:
                NSLog(@"player item status is ready to play");
                Float64 duration = CMTimeGetSeconds(self.avPlayer.currentItem.duration);
                NSLog(@"Duration--> %f",duration) // NaN returns
                break;
            case AVPlayerItemStatusUnknown:
                NSLog(@"player item status is unknown");
                break;
        }
    }else if ([keyPath isEqualToString:@"playbackBufferEmpty"]){
        if (item.playbackBufferEmpty){
            NSLog(@"player item playback buffer is empty");
        }
    }
}
}

Answer 1

感谢您的支持 friend ，最后我找到了问题的解决方案而不是使用 AVPlayer 我使用 AVAudioPlayer 并且我解决了问题并且我得到了音频持续时间。

NSString* resourcePath = @"http://9xmusiq.com/songs2/tamil/Kaatru%20Veliyidai/Azhagiye%20%5bStarmusiq.cc%5d.mp3"; //your url
NSData *_objectData = [NSData dataWithContentsOfURL:[NSURL URLWithString:resourcePath]];
NSError *error;

AVAudioPlayer *player1 = [[AVAudioPlayer alloc] initWithData:_objectData error:&error];
player1.numberOfLoops = 0;
player1.volume = 1.0f;
[player1 prepareToPlay];

NSLog(@"Total Duration : %f",player1.duration);

if (player1 == nil){
    NSLog(@"%@", [error description]);
}else{
    [player1 play];
}