ios - WebRTC iOS SignalEncoderTimedOut

Question

我尝试将视频从 iOS 设备翻译到 Chrome 浏览器。在 iOS 上，我正在执行以下操作:

let conf=RTCConfiguration()
conf.iceServers=[RTCIceServer(urlStrings: ["stun:stun.l.google.com:19302"])]
let cond=RTCMediaConstraints.init(mandatoryConstraints: ["OfferToReceiveAudio":"true","OfferToReceiveVideo":"true"], optionalConstraints: [:])
self.conn=fact?.peerConnection(with: conf, constraints: cond, delegate: self)
let mcons=RTCMediaConstraints.init(mandatoryConstraints: [:], optionalConstraints: [:])
let asrc=fact?.audioSource(with: mcons)
let atrk=self.fact!.audioTrack(with: asrc!, trackId: "aud")
atrk.isEnabled=true
conn?.add(atrk, streamIds: ["str"])

let vsrc=self.fact!.videoSource()
self.vcap=RTCCameraVideoCapturer.init(delegate: vsrc)
let vtrk=self.fact!.videoTrack(with: vsrc, trackId: "vid")
conn?.add(vtrk, streamIds: ["str"])
vtrk.isEnabled=true

conn?.offer(for: RTCMediaConstraints.init(mandatoryConstraints: ["OfferToReceiveAudio":"true","OfferToReceiveVideo":"true"], optionalConstraints: nil), completionHandler: {
    (sdp,err) in do {
       ...    
    }
}
func peerConnection(_ peerConnection: RTCPeerConnection, didChange newState: RTCIceConnectionState) {
    switch newState {
     ...
    case RTCIceConnectionState.connected:
        self.log(msg: "RTCIceConnectionState: connected")

        DispatchQueue.main.async {
            let cam=AVCaptureDevice.default(.builtInWideAngleCamera, for: AVMediaType.video, position: .back)
            let formats=RTCCameraVideoCapturer.supportedFormats(for: cam!)
            let form=formats[0]
            self.vcap!.startCapture(with: cam!, format: form, fps: 10) {
                err in
            }
        }
        break
        ...
    }
}

我连接成功，对方有音视频轨，但是没有视频传输。iOS devive 上的日志向我显示了以下行:

 (video_send_stream_impl.cc:580): SignalEncoderTimedOut, Encoder timed out.

如何让视频翻译工作？

我也看到音频捕获和传输，但没有听到 chrome 的声音。

GoogleWebRTC (1.1.23260)

iOS 11.3.1(iPhone SE)

Xcode 9.3.1 (9E501)

MacOS 上的 Chrome 66.0.3359.181 64 位

Answer 1

保留vsrc解决了问题