Sample audio https://dl.espressif.com/dl/audio/ff-16b-2c-44100hz.m4a
func playAudio(with url: URL) {
do {
let data = try Data(contentsOf: url)
player = try AVAudioPlayer(data: data)
player?.prepareToPlay()
player?.play()
} catch {
print("failed to play with error: \(error)")
}
}func playFromBundle() {
guard let url = Bundle.main.url(forResource: "timeless", withExtension: ".mp3") else {
fatalError("resource not found")
}
do {
try AVAudioSession.sharedInstance().setCategory(.playback)
player = try AVAudioPlayer(contentsOf: url)
player?.play()
} catch {
print("audio playback error: \(error)")
}
}func exportUsingComposition() {
guard let url = URL(string: mp3AudioFile) else {
return
}
let asset = AVURLAsset(url: url, options: nil) // https://developer.apple.com/documentation/avfoundation/avurlasset
let composition = AVMutableComposition()
let compositionAudioTrack = composition.addMutableTrack(withMediaType: .audio, preferredTrackID: CMPersistentTrackID(kCMPersistentTrackID_Invalid))
let sourceAudioTrack = asset.tracks(withMediaType: AVMediaType.audio).first!
do {
try compositionAudioTrack?.insertTimeRange(CMTimeRange(start: CMTime.zero, duration: asset.duration), of: sourceAudioTrack, at: CMTime.zero)
} catch {
print("failed exportUsingComposition: \(error)")
}
let compatiblePresets = AVAssetExportSession.exportPresets(compatibleWith: composition)
var preset: String = AVAssetExportPresetPassthrough
if compatiblePresets.contains(AVAssetExportPresetAppleM4A) {
preset = AVAssetExportPreset1920x1080 // can change preset here - see doc for more presets
}
guard let exportSession = AVAssetExportSession(asset: composition, presetName: preset),
exportSession.supportedFileTypes.contains(.mp4) else {
fatalError("file type NOT supported")
}
let documentsDir = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
let trimmedFileURL = documentsDir.appendingPathComponent(filename)
print(trimmedFileURL)
if FileManager.default.fileExists(atPath: trimmedFileURL.path) {
print("file exists")
try? FileManager.default.removeItem(at: trimmedFileURL)
} else {
print("file does not exist")
}
exportSession.outputURL = trimmedFileURL
exportSession.outputFileType = .mp4
let startTime = CMTime(value: 0, timescale: 1)
let stopTime = CMTime(value: 3, timescale: 1)
exportSession.timeRange = CMTimeRange(start: startTime, end: stopTime)
exportSession.exportAsynchronously {
print("export complete \(exportSession.status)")
switch exportSession.status {
case .cancelled:
print("cancelled")
case .failed:
print("failed \(exportSession.error?.localizedDescription ?? "")")
case .exporting:
print("exporting")
case .completed:
print("completed")
self.playAudio(with: trimmedFileURL)
case .waiting:
print("waiting")
case .unknown:
print("unknown")
default:
print("future case")
}
}
}func playFileFromDocumentsDirectory() {
let docDir = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
let fileURL = docDir.appendingPathComponent(filename)
playAudio(with: fileURL)
}