player.duration shows always zero in MPMoviePlayerController for video file - iphone

Question

I am playing a small video in mpmediaplayer controller using this code
MPMoviePlayerController *player = [[MPMoviePlayerController alloc]
initWithContentURL:[NSURL fileURLWithPath:videostr]];
where videostr is path of that video file.
Now i need to get length of that video file for that i am using this code.
length = player.duration;
But it always shows 0.000. But the video is playing well.
I am checking by googling every where code to get video duration is player.duration only.
And i try some other code also
AVURLAsset *asset = [[[AVURLAsset alloc] initWithURL:[NSURL fileURLWithPath:videostr]
options:[NSDictionary dictionaryWithObjectsAndKeys:[NSNumber numberWithBool:YES], AVURLAssetPreferPreciseDurationAndTimingKey, nil]] autorelease];
NSTimeInterval duration;
if (asset)
duration = CMTimeGetSeconds(asset.duration) ;
NSLog(#">>>>>>>>>>>>>>>>>>>> %f", asset.duration);
even though it shows zero.Can any one please help me.
Thank in advance.

Answer 1

You can not get a useful duration until the content is actually playable.
Register for load state changes:
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(MPMoviePlayerLoadStateDidChange:)
name:MPMoviePlayerLoadStateDidChangeNotification
object:nil];
Evaluate the state once being notified:
- (void)MPMoviePlayerLoadStateDidChange:(NSNotification *)notification
{
if ((player.loadState & MPMovieLoadStatePlaythroughOK) == MPMovieLoadStatePlaythroughOK)
{
NSLog(#"content play length is %g seconds", player.duration);
}
}

Answer 2

SWIFT
You can do in swift like this
func getMediaDuration(url: NSURL!) -> Float64{
var asset : AVURLAsset = AVURLAsset.assetWithURL(url) as AVURLAsset
var duration : CMTime = asset.duration
return CMTimeGetSeconds(duration)
}

Answer 3

use MPMovieDurationAvailableNotification
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(movieDurationAvailable:)
MPMovieDurationAvailableNotification object:nil];
- (void)movieDurationAvailable:(NSNotification *)notification {
NSLog(#"content play length is %g seconds", moviePlayer.duration);
}

Answer 4

You can fetch time duration from video file using below code.
NSURL *videoURL = [NSURL fileURLWithPath:VideoFileURL];
AVURLAsset *sourceAsset = [AVURLAsset URLAssetWithURL:videoURL options:nil];
CMTime duration = sourceAsset.duration;
double durationInSeconds = duration.value/duration.timescale;
In durationInSeconds variable you get the exact duration in seconds.