AVAudioPlayer returns wrong duration for audio file

Question

I'm trying to play an audio file in my app, and I want to show progress of playing file.

The file completely plays but I can't get correct duration of file to display. The returned value is considerably lower than the actual duration. For example it returns 1 second for a 4-Seconds audio file, or 9 seconds for a 41-Seconds one.

Please do not say it only returns correct value while playing, because I tried that too and it doesn't. I always get 1 second for any file using AVAudioPlayer duration method, and I tried the solution here via AVURLAssets I get that weird 9 seconds instead of 41 !

There's also another problem with AVAudioPlayer. It plays the file but meanwhile its isPlaying method returns NO

I don't know if it makes any difference but my audio file is an AMR file.

Any help is really appreciated. Thanks.

**** UPDATE : I TRIED WITH OTHER FILES, IT WORKS FINE, SO NOW, I NEED TO GET THE DURATION OF AN AMR AUDIO FILE ****

Answer 1

The below code may help you to get the right progress on slider

NSURL *soundFileURL = [NSURL fileURLWithPath:path];
NSError *error;
_audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:soundFileURL error:&error];
_sliderSong.maximumValue = _audioPlayer.duration; //_sliderSong is a UISlider property
_sliderSong.value = 0.0; //_audioPlayer is a AVAudioPlayer property
[NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(updateTime:) userInfo:nil repeats:YES];

if (error)
{
    NSLog(@"Error in audioPlayer: %@",
          [error localizedDescription]);
} else {
    _audioPlayer.delegate = self;
    [_audioPlayer prepareToPlay];
    [_audioPlayer play];
}
}
- (IBAction)slide { //called when we drag the slider explicitly (we have to bind it with slider) 
    _audioPlayer.currentTime = _sliderSong.value;
}
- (void)updateTime:(NSTimer *)timer { //slider updation
    _sliderSong.value = _audioPlayer.currentTime;
}