Audio Duration problem After being exported by AVAssestExportSession

[d4devil]

Hello All,

I have been working on a audio application where a user records the audio and later I have to give user the facility to edit that recorded audio as well. The audio being recorded is in .caf format.. herez the code for the setting em using to record the audio

AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    NSError *err = nil;
    [audioSession setCategory :AVAudioSessionCategoryPlayAndRecord error:&err];

    [audioSession setActive:YES error:nil];

    NSMutableDictionary *recordSetting = [[NSMutableDictionary alloc] init];

    [recordSetting setValue :[NSNumber numberWithInt:kAudioFormatAppleeIMA4 ] forKey:AVFormatIDKey];
    [recordSetting setValue:[NSNumber numberWithFloat:44100.0] forKey:AVSampleRateKey]; 
    [recordSetting setValue:[NSNumber numberWithInt: 2] forKey:AVNumberOfChannelsKey];

    [recordSetting setValue :[NSNumber numberWithInt:128000] forKey:AVEncoderBitRateKey ];
    [recordSetting setValue :[NSNumber numberWithInt:AVAudioQualityMax] forKey:AVEncoderAudioQualityKey ];

I have also developed a function where user can trim an existing audio file by giving the start and end time to create a new audio file. Everything is working fine and audio is being trimmed But after trimming my device/simulator cannot read the duration of the new audio file and displays like -3294323423.9000 etc. Here is the code I am using to trim the audio

-(IBAction) cutButtonTapped: (id) sender {

// inSeconds and outSeconds are float variables which value is being set using the UISlider

if ((inSeconds > 0) && (outSeconds > 0)) {
    if (inSeconds > outSeconds) {
        NSLog(@"inSeconds should not be greater than outSeconds";
        return;
    }

    CMTime inTime = CMTimeMakeWithSeconds(inSeconds, 600);
    CMTime outTime = CMTimeMakeWithSeconds(outSeconds, 600);
    CMTime duration = CMTimeSubtract(outTime, inTime);
    CMTimeRange editRange = CMTimeRangeMake(inTime, duration);
    NSError *editError = nil;
    // Composition is an AVMutableComposition Object which is already initialized 
    [composition insertTimeRange:editRange
                         ofAsset:sourceAsset
                          atTime:composition.duration 
                           error:&editError];
    if (!editError) {

        timeSlider.maximumValue = 
        CMTimeGetSeconds (composition.duration);
    } else {
        NSLog (@"edit error: %@", editError);
    }

    // reset edit points
    inSeconds = -1;
    outSeconds = -1;
    inLabel.text = @"-:--:--";
    outLabel.text = @"-:--:--";
            [self exportAudio];
}

}

ANd finnally exporting the audio file to url path.

AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:composition
                                                                       presetName:AVAssetExportPresetMediumQuality];
NSLog (@"can export: %@", exportSession.supportedFileTypes);
NSArray *dirs = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectoryPath = [dirs objectAtIndex:0];
NSString *exportPath = [documentsDirectoryPath stringByAppendingPathComponent:@"newAudio.caf"];
NSLog(@"Doc Path: %@", exportPath);
[[NSFileManager defaultManager] removeItemAtPath:exportPath error:nil];
NSURL *exportURL = [NSURL fileURLWithPath:exportPath];
exportSession.outputURL = exportURL;
exportSession.outputFileType = @"com.apple.m4a-audio";
NSLog(@"File Types: %@" , exportSession.supportedFileTypes);
[exportSession exportAsynchronouslyWithCompletionHandler:^{
    NSLog (@"status is %d",
           exportSession.status);
    switch (exportSession.status) {
        case AVAssetExportSessionStatusFailed:
        case AVAssetExportSessionStatusCompleted: {
            [self performSelectorOnMainThread:@selector (doPostExportUICleanup:)
                                   withObject:nil
                                waitUntilDone:NO];
            break;
        }
    };
}];
exportProgressView.progress = 0.0;
exportProgressView.hidden = NO;
exportTimer = [NSTimer scheduledTimerWithTimeInterval:0.1
   target:self
 selector:@selector (updateExportProgress:)
 userInfo:exportSession repeats:YES];   

}

Please tell me where I am doing it wrong. Any help will be greatly appreciated and to improve the code any suggestion will also be highly encouraged. I have also posted almost the whole code so that it might help someone else who is looking for the same solution.

[d4devil]

is there no one who can help me ... guys i really need to solve this issue asap ..