How can I overlap audio files and combine for iPhone in Xcode?

2 Solutions Collect From Internet About “How can I overlap audio files and combine for iPhone in Xcode?”

Here’s what I did in my app.

- (void) setUpAndAddAudioAtPath:(NSURL*)assetURL toComposition:(AVMutableComposition *)composition
    AVURLAsset *songAsset = [AVURLAsset URLAssetWithURL:assetURL options:nil];

    AVMutableCompositionTrack *track = [composition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
    AVAssetTrack *sourceAudioTrack = [[songAsset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0];

    NSError *error = nil;
    BOOL ok = NO;

    CMTime startTime = CMTimeMakeWithSeconds(0, 1);
    CMTime trackDuration = songAsset.duration;
    //CMTime longestTime = CMTimeMake(848896, 44100); //(19.24 seconds)
    CMTimeRange tRange = CMTimeRangeMake(startTime, trackDuration);

    //Set Volume
    AVMutableAudioMixInputParameters *trackMix = [AVMutableAudioMixInputParameters audioMixInputParametersWithTrack:track];
    [trackMix setVolume:0.8f atTime:startTime];
    [self.audioMixParams addObject:trackMix];

    //Insert audio into track
    ok = [track insertTimeRange:tRange ofTrack:sourceAudioTrack atTime:CMTimeMake(0, 44100) error:&error];

- (IBAction)saveRecording
     AVMutableComposition *composition = [AVMutableComposition composition];
        audioMixParams = [[NSMutableArray alloc] initWithObjects:nil];

    //Add Audio Tracks to Composition
    NSString *URLPath1 = [[NSBundle mainBundle] pathForResource:@"mysound" ofType:@"mp3"];
    NSString *URLPath2 = [[NSBundle mainBundle] pathForResource:@"mysound2" ofType:@"mp3"];
    NSURL *assetURL1 = [NSURL fileURLWithPath:URLPath1];
    [self setUpAndAddAudioAtPath:assetURL1   toComposition:composition];

    NSURL *assetURL2 = [NSURL fileURLWithPath:URLPath2];
    [self setUpAndAddAudioAtPath:assetURL2   toComposition:composition];

    AVMutableAudioMix *audioMix = [AVMutableAudioMix audioMix];
    audioMix.inputParameters = [NSArray arrayWithArray:audioMixParams];

    //If you need to query what formats you can export to, here's a way to find out
    NSLog (@"compatible presets for songAsset: %@",
           [AVAssetExportSession exportPresetsCompatibleWithAsset:composition]);

    AVAssetExportSession *exporter = [[AVAssetExportSession alloc]
                                      initWithAsset: composition
                                      presetName: AVAssetExportPresetAppleM4A];
    exporter.audioMix = audioMix;
    exporter.outputFileType = @"";
    NSURL *exportURL = [NSURL fileURLWithPath:exportFile];
    exporter.outputURL = exportURL;

// do the export
        [exporter exportAsynchronouslyWithCompletionHandler:^{
            int exportStatus = exporter.status;
            NSError *exportError = exporter.error;

            switch (exportStatus) {
                case AVAssetExportSessionStatusFailed:


                case AVAssetExportSessionStatusCompleted: NSLog (@"AVAssetExportSessionStatusCompleted"); 
                case AVAssetExportSessionStatusUnknown: NSLog (@"AVAssetExportSessionStatusUnknown"); break;
                case AVAssetExportSessionStatusExporting: NSLog (@"AVAssetExportSessionStatusExporting"); break;
                case AVAssetExportSessionStatusCancelled: NSLog (@"AVAssetExportSessionStatusCancelled"); break;
                case AVAssetExportSessionStatusWaiting: NSLog (@"AVAssetExportSessionStatusWaiting"); break;
                default:  NSLog (@"didn't get export status"); break;

Beware that I did do this a while ago, and you might have to work with it a tiny bit to make it work. But it did work at one point. Let me know if you’re having problems.

If Audio Asset track is not found in selected asset.You can use this statement to check the sound of particular Video.

if([[songAsset tracksWithMediaType:AVMediaTypeAudio] firstObject]==NULL)
    NSLog(@"Sound is not Present");
    NSLog(@"Sound is Present");
    //You will initalise all things
    AVAssetTrack *sourceAudioTrack = [[songAsset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0];