iOS Audio Trimming

Question

I searched a lot and couldn\'t find anything relevant... I am working on iOS audio files and here is what I want to do...

1. Record Audio and Save Clip (Checked,

Answer 1

Here is a sample code which trim audio file from starting & ending offset and save it back. Please check this iOS Audio Trimming.

// Path of your source audio file
NSString *strInputFilePath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"abc.mp3"];
NSURL *audioFileInput = [NSURL fileURLWithPath:strInputFilePath];

// Path of your destination save audio file
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES);
    NSString *libraryCachesDirectory = [paths objectAtIndex:0];
    libraryCachesDirectory = [libraryCachesDirectory stringByAppendingPathComponent:@"Caches"];

NSString *strOutputFilePath = [NSString stringWithFormat:@"%@%@",libraryCachesDirectory,@"/abc.mp4"];
NSURL *audioFileOutput = [NSURL fileURLWithPath:strOutputFilePath];

if (!audioFileInput || !audioFileOutput)
{
    return NO;
}

[[NSFileManager defaultManager] removeItemAtURL:audioFileOutput error:NULL];
AVAsset *asset = [AVAsset assetWithURL:audioFileInput];

AVAssetExportSession *exportSession = [AVAssetExportSession exportSessionWithAsset:asset presetName:AVAssetExportPresetAppleM4A];

if (exportSession == nil)
{
    return NO;
}
float startTrimTime = 0; 
float endTrimTime = 5;

CMTime startTime = CMTimeMake((int)(floor(startTrimTime * 100)), 100);
CMTime stopTime = CMTimeMake((int)(ceil(endTrimTime * 100)), 100);
CMTimeRange exportTimeRange = CMTimeRangeFromTimeToTime(startTime, stopTime);

exportSession.outputURL = audioFileOutput;
exportSession.outputFileType = AVFileTypeAppleM4A;
exportSession.timeRange = exportTimeRange;

[exportSession exportAsynchronouslyWithCompletionHandler:^
{
    if (AVAssetExportSessionStatusCompleted == exportSession.status)
    {
        NSLog(@"Success!");
    }
    else if (AVAssetExportSessionStatusFailed == exportSession.status)
    {
        NSLog(@"failed");
    }
}];