load a pcm into a AVAudioPCMBuffer

Question

I have this code:

func loadSoundfont(_ pitch : String) {
    let path: String = Bundle.main.path(forResource: "\(self.id)/\(pitch)", ofType: "f32")!
    let url = URL(fileURLWithPath: path)

    do {
        let file = try AVAudioFile(forReading: url, commonFormat: AVAudioCommonFormat.pcmFormatFloat32, interleaved: true)
        let format = file.processingFormat
        let capacity = AVAudioFrameCount(file.length)
        self.buffer = AVAudioPCMBuffer(pcmFormat: format, frameCapacity: capacity)
        try file.read(into: self.buffer!)
    } catch let error as NSError {
        print("ERROR HERE", error.localizedDescription)
    }
}

And I get the following error: 1954115647 which is: kAudioFileUnsupportedFileTypeError

My A4.f32 file contains a PCM float 32. Is there something I'm missing here? There's no header in my file, is it something that could lead to this problem?

Your audio file is raw float32 data? I don't think `AVFoundation` will load that for you. Either load it yourself or put a header on it. — Rhythmic Fistman, Dec 13 '16 at 23:49
@RhythmicFistman Perhaps you can help me here: https://stackoverflow.com/questions/55306996/playing-wav-data-with-avaudioengine — aleclarson, Mar 22 '19 at 20:37

score 1 · Accepted Answer · answered Dec 16 '16 at 15:29

Thanks to Rhythmic Fistman in the comments, I went and loaded it myself, that way:

func loadSoundfont(_ pitch : String) {
    let path: String = Bundle.main.path(forResource: "\(self.id)/\(pitch)", ofType: "f32")!
    let url = URL(fileURLWithPath: path)

    do {
        let data = try Data(contentsOf: url)
        let format = AVAudioFormat(commonFormat: .pcmFormatFloat32, sampleRate: 44100, channels: 2, interleaved: true)

        self.buffer = AVAudioPCMBuffer(pcmFormat: format, frameCapacity: AVAudioFrameCount(data.count))

        self.buffer!.floatChannelData!.pointee.withMemoryRebound(to: UInt8.self, capacity: data.count) {
            let stream = OutputStream(toBuffer: $0, capacity: data.count)
            stream.open()
            _ = data.withUnsafeBytes {
                stream.write($0, maxLength: data.count)
            }
            stream.close()
        }

    } catch let error as NSError {
        print("ERROR HERE", error.localizedDescription)
    }
}

load a pcm into a AVAudioPCMBuffer

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