问题
I am currently trying to implement a simple audio recording tool on my Mac. Since I need the raw audio buffers in-memory, I cannot use AVAudioRecorder, which would just write the recording to a file.
My approach is to create a AVCaptureSession, Input(Microphone) and Output(AVCaptureAudioDataOutput) and start the session. Everything works fine, however the delegate callback of the output is never called.
I made sure to add mic/camera permissions (just in case) in the project settings.
Maybe someone can help me with this!
Here's my code:
import Foundation
import AVFoundation
class AudioCaptureSession: NSObject, AVCaptureAudioDataOutputSampleBufferDelegate {
let settings = [
AVFormatIDKey: kAudioFormatMPEG4AAC,
AVNumberOfChannelsKey : 1,
AVSampleRateKey : 44100]
let captureSession = AVCaptureSession()
override init() {
super.init()
let queue = DispatchQueue(label: "AudioSessionQueue", attributes: [])
let captureDevice = AVCaptureDevice.default(for: AVMediaType.audio)
var audioInput : AVCaptureDeviceInput? = nil
var audioOutput : AVCaptureAudioDataOutput? = nil
do {
try captureDevice?.lockForConfiguration()
audioInput = try AVCaptureDeviceInput(device: captureDevice!)
captureDevice?.unlockForConfiguration()
audioOutput = AVCaptureAudioDataOutput()
audioOutput?.setSampleBufferDelegate(self, queue: queue)
audioOutput?.audioSettings = settings
} catch {
print("Capture devices could not be set")
print(error.localizedDescription)
}
if audioInput != nil && audioOutput != nil {
captureSession.beginConfiguration()
if (captureSession.canAddInput(audioInput!)) {
captureSession.addInput(audioInput!)
} else {
print("cannot add input")
}
if (captureSession.canAddOutput(audioOutput!)) {
captureSession.addOutput(audioOutput!)
} else {
print("cannot add output")
}
captureSession.commitConfiguration()
print("Starting capture session")
captureSession.startRunning()
}
}
func captureOutput(_ output: AVCaptureOutput,
didOutput sampleBuffer: CMSampleBuffer,
from connection: AVCaptureConnection) {
print("Audio data recieved")
}
}
回答1:
It's called for me. You don't show how you use it, but maybe your AudioCaptureSession
is going out of scope and being deallocated.
来源:https://stackoverflow.com/questions/49598691/macos-swift-capture-audio-with-avcapturesession