AudioFile trimming not working - ios

Question

in my app i am trim the audio file.
but its not working every-time its showing me failed
this is my code
#IBAction func trimAudioPressed(sender: AnyObject) {
isTrim = true
let audioFileInput = filepath
let date = NSDate()
let formatter = NSDateFormatter()
formatter.dateFormat = "yyyy_MMM_dd_HH_mm_ss"
let strdate = formatter.stringFromDate(date)
print(NSUserDefaults.standardUserDefaults().valueForKey("fileURL"))
let extensionofFile = filepath.pathExtension!
let strOutputFilePath123 : String = String(filepath.URLByDeletingLastPathComponent!)
strOutputFilePath = "\(strOutputFilePath123)\(strdate).\(extensionofFile)"
let fileManger = NSFileManager.defaultManager()
if fileManger.fileExistsAtPath(strOutputFilePath) {
do {
(try fileManger.removeItemAtPath(strOutputFilePath))
}
catch let error { print(error)
}
}
let audioFileOutput : NSURL = NSURL(string: strOutputFilePath)!
let asset = AVAsset(URL: audioFileInput)
let succcess = self.exportAsset(asset, toFilePath: strOutputFilePath)
print(succcess)
self.dismissView()
}
func exportAsset(avAsset: AVAsset, toFilePath filePath: String) -> Bool {
var tracks = avAsset.tracksWithMediaType(AVMediaTypeAudio)
if tracks.count == 0 {
return false
}
let track = tracks[0]
let exportSession = AVAssetExportSession(asset: avAsset, presetName: AVAssetExportPresetAppleM4A)
let supportedTypeArray = exportSession!.supportedFileTypes
for str: String in supportedTypeArray {
if nil == exportSession {
return false
}
}
print(leftV)
print(rightV)
let startTime = CMTimeMake(Int64(leftV), 1)
let stopTime = CMTimeMake(Int64(rightV), 1)
let exportTimeRange = CMTimeRangeFromTimeToTime(startTime, stopTime)
let exportAudioMix = AVMutableAudioMix()
let exportAudioMixInputParameters = AVMutableAudioMixInputParameters(track: track)
exportAudioMix.inputParameters = [exportAudioMixInputParameters]
exportSession!.outputURL = NSURL.fileURLWithPath(filePath)
exportSession!.outputFileType = AVFileTypeAppleM4A
exportSession!.timeRange = exportTimeRange
exportSession!.audioMix = exportAudioMix
exportSession!.exportAsynchronouslyWithCompletionHandler({() -> Void in
if .Completed == exportSession!.status {
print("Success")
}
else if .Failed == exportSession!.status {
print("Failed")
print("Export Session Status: \(exportSession!.status)")
}
else {
print("Export Session Status: \(exportSession!.status)")
}
})
return true
}
i dont know where its going wrong
here is my string inputfile path
file:///private/var/mobile/Containers/Data/Application/07166600-AAEA-436F-BE6B-93839C180F19/Documents/Default/recording-2016-08-31-18-28-12.m4a
here is my output file path
file:///private/var/mobile/Containers/Data/Application/07166600-AAEA-436F-BE6B-93839C180F19/Documents/Default/2016_Aug_31_18_38_31.m4a
or even starttime and stop time is also perfect. so how can i solve this. and let me knonw if there is any other approch.
this is the error which i got
export failed Optional(Error Domain=NSURLErrorDomain Code=-3000 "Cannot create file" UserInfo={NSLocalizedDescription=Cannot create file, NSUnderlyingError=0x7fc9415142b0 {Error Domain=NSOSStatusErrorDomain Code=-12115 "(null)"}})

Answer 1

The line
exportSession!.outputURL = NSURL.fileURLWithPath(filePath)
is wrong. filePath is not a path; it is already a file:// URL.
The quick fix is to change the outputURL to this:
exportSession!.outputURL = NSURL(string: filePath)!
There's confusion between file paths and file URLs in this code. e.g. filepath is a file NSURL, but strOutputFilePath123 is a String that contains a file:// scheme URI.
To convert a file NSURL to a String path, you should use url.path.