I try to convert opus file to mp3/wav file But I get this error: opus codec not supported in WAVE format. for example I can 1. convert opus file to ogg but not for mp3/wav 2. convert mp3 file to wav file My code, can you please advise what I am do wrong? Thanks override func viewDidLoad() { super.viewDidLoad() input = Bundle.main.path(forResource: "example", ofType: "opus") let documents = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0] output = documents.appending("/result1.wav") self.convertAudio() } func convertAudio(){ self.ff.convertInputPath(input, outputPath: output, options: nil, progressBlock: { (bytesRead :UInt, totalBytesRead : UInt64, totalBytesExpectedToRead : UInt64) in print("OK") }) { (value, error) in print(error ?? "") } }