WebRTC replaceTrack, getStats not returning audioInputLevel - webrtc

I have a WebRTC stream which is sending audio/video, I am displaying the volume in a meter widget which is retrieved from a getStats call on the peerConnection.
getStats(function (stats) {
var results = stats.result()
for (let i=0; i < results.length; i++) {
var res = results[i]
if (res.type == 'ssrc') {
volume = parseInt(res.stat('audioInputLevel'))
}
}
})
This is working fine, the issue is when I run replaceTrack to update the streams audio/video the above getStats returns 0 for the audio level.
navigator.mediaDevices.getUserMedia(media)
.then(stream => {
const tracks = stream.getTracks()
peerConnection.getSenders()
.forEach(sender => {
const newTrack = tracks.find(track => track.kind === sender.track.kind)
sender.replaceTrack(newTrack)
})
})
The local stream get's updated, the remote user get's updated and audio / video is working. But getStats is no longer returning the audioInputLevel.
Would anyone be able to help me understand why? Or what a fix maybe.
Thanks

audioLevel is broken in spec-stats, see https://bugs.chromium.org/p/chromium/issues/detail?id=920630#c16 and the linked bugs.

Related

A better way to handle async saving to backend server and cloud storage from React Native app

In my React Native 0.63.2 app, after user uploads images of artwork, the app will do 2 things:
1. save artwork record and image records on backend server
2. save the images into cloud storage
Those 2 things are related and have to be done successfully all together. Here is the code:
const clickSave = async () => {
console.log("save art work");
try {
//save artwork to backend server
let art_obj = {
_device_id,
name,
description,
tag: (tagSelected.map((it) => it.name)),
note:'',
};
let img_array=[], oneImg;
imgs.forEach(ele => {
oneImg = {
fileName:"f"+helper.genRandomstring(8)+"_"+ele.fileName,
path: ele.path,
width: ele.width,
height: ele.height,
size_kb:Math.ceil(ele.size/1024),
image_data: ele.image_data,
};
img_array.push(oneImg);
});
art_obj.img_array = [...img_array];
art_obj = JSON.stringify(art_obj);
//assemble images
let url = `${GLOBAL.BASE_URL}/api/artworks/new`;
await helper.getAPI(url, _result, "POST", art_obj); //<<==#1. send artwork and image record to backend server
//save image to cloud storage
var storageAccessInfo = await helper.getStorageAccessInfo(stateVal.storageAccessInfo);
if (storageAccessInfo && storageAccessInfo !== "upToDate")
//update the context value
stateVal.updateStorageAccessInfo(storageAccessInfo);
//
let bucket_name = "oss-hz-1"; //<<<
const configuration = {
maxRetryCount: 3,
timeoutIntervalForRequest: 30,
timeoutIntervalForResource: 24 * 60 * 60
};
const STSConfig = {
AccessKeyId:accessInfo.accessKeyId,
SecretKeyId:accessInfo.accessKeySecret,
SecurityToken:accessInfo.securityToken
}
const endPoint = 'oss-cn-hangzhou.aliyuncs.com'; //<<<
const last_5_cell_number = _myself.cell.substring(myself.cell.length - 5);
let filePath, objkey;
img_array.forEach(item => {
console.log("init sts");
AliyunOSS.initWithSecurityToken(STSConfig.SecurityToken,STSConfig.AccessKeyId,STSConfig.SecretKeyId,endPoint,configuration)
//console.log("before upload", AliyunOSS);
objkey = `${last_5_cell_number}/${item.fileName}`; //virtual subdir and file name
filePath = item.path;
AliyunOSS.asyncUpload(bucket_name, objkey, filePath).then( (res) => { //<<==#2 send images to cloud storage with callback. But no action required after success.
console.log("Success : ", res) //<<==not really necessary to have console output
}).catch((error)=>{
console.log(error)
})
})
} catch(err) {
console.log(err);
return false;
};
};
The concern with the code above is that those 2 async calls may take long time to finish while user may be waiting for too long. After clicking saving button, user may just want to move to next page on user interface and leaves those everything behind. Is there a way to do so? is removing await (#1) and callback (#2) able to do that?
if you want to do both tasks in the background, then you can't use await. I see that you are using await on sending the images to the backend, so remove that and use .then().catch(); you don't need to remove the callback on #2.
If you need to make sure #1 finishes before doing #2, then you will need to move the code for #2 intp #1's promise resolving code (inside the .then()).
Now, for catching error. You will need some sort of error handling that alerts the user that an error had occurred and the user should trigger another upload. One thing you can do is a red banner. I'm sure there are packages out there that can do that for you.

MediaRecorder has a delay of multiple seconda

I'm trying to use a MediaRecorder to record a MediaStream and display it in a video element using a MediaSource. So the setup looks like:
Request a MediaStream from the browser
Add it to the MediaRecorder
Add the recorded blobs to the MediaSource Buffer
The result looks very good but there is one problem: There is a delay in the playback.
When displaying the MediaStream directly there is no delay so I sorted out the first bulletpoint as the problem.
Nevertheless, it seems like either the MediaRecorder or the MediaSource is adding a delay of about 3 seconds to the stream.
this.screenRecording = await mediaDevices.getDisplayMedia({ video: { frameRate: 60, resizeMode: 'none' } });
const mediaRecorder = new MediaRecorder(this.screenRecording);
mediaRecorder.ondataavailable = async (event: any) => {
if (this.screenReceiving.readyState === 'open') {
if (this.screenReceivingBuffer == null) {
this.screenReceivingBuffer = this.screenReceiving.addSourceBuffer('video/webm;codecs=vp8');
}
if (!this.screenReceivingBuffer.updating) {
this.screenReceivingBuffer.appendBuffer(await new Response(event.data).arrayBuffer());
}
}
};
mediaRecorder.start(16);
The above code is only copy & paste from the actual project so please don't expect it to work by copy & paste ;)
Does anyone have an idea why this delay exists?
Any ideas on how to tweak the browser to not add this delay?

How to check the sdp plan (plan-b or unified-plan) used in RTCPeerConnection object in Safari (and all browsers)?

How to check the sdp plan (plan-b or unified-plan) used in RTCPeerConnection object?
I know in Chrome I can call:
var p = new RTCPeerConnection()
console.log('plan:', p.getConfiguration().sdpSemantics)
The sdpSemantics works on Chrome, but does not have on Safari, how to check that on Safari?
After my research, it looks like there is no simple solution for this to be sure.
However, according to the docs, we can differentiate Plan-b / unified-plan by how the SDP looks like when there is more than 1 track of one kind.
In the unified plan, every track of the same kind has a separate m= section in the SDP, while in Plan-B they are grouped together.
Here is the working code snippet:
function isUnifiedPlanEnabled() {
const canvas = document.createElement('canvas');
const track = canvas.captureStream(1).getTracks()[0];
const pc = new RTCPeerConnection();
pc.addTrack(track);
pc.addTrack(track.clone());
return pc.createOffer().then(offer => {
const sdpRows = offer.sdp.split('\n')
const mVideoRows = sdpRows.filter(row => row.indexOf('m=video') === 0)
return mVideoRows.length === 2
})
}

setSinkId change muliple audio ouputs

Here is the problem,
First I enumerate all the devices that I have available with in select elements:
navigator.mediaDevices.enumerateDevices()
When I change one output, it sounds in the device that I choose.
HTMLMediaElement.setSinkId(deviceId)
After if I play another audio and change the device output (setSinkId), it changes also the first one to the last deviceId. So I have both sounds in the same device.
Do I need to have the last adapter.js version to implement properly that problem?
********* EDITED **********
Following the above comment, it try the web audio, but not success. With getUserMedia everything is fine.
navigator.getUserMedia( { audio: true, video: false },
function (mediaStream) {
// Create an audio context for the audio
var ac = new (window.AudioContext || window.webKitAudioContext)();
// Create a clone of the stream, if not the id of all the stream is default
//var streamClone = stream.clone();
var ss = ac.createMediaStreamSource(mediaStream);
// Create a destination
var sd = ac.createMediaStreamDestination()
ss.connect(sd);
element.srcObject = sd.stream;
// Play the sound
element.play();
element.setSinkId(deviceId).then(function() {
console.log('Set deviceId('+deviceId+') in the selected audio element');
});
},
function (error) {
console.log(error);
}
);
But using my remote stream, I cannot get any noise
var ac = new (window.AudioContext || window.webKitAudioContext)();
// Create a clone of the stream, if not the id of all the stream is default
var streamClone = stream.clone();
var ss = ac.createMediaStreamSource(stream);
// Create a destination
var sd = ac.createMediaStreamDestination()
ss.connect(sd);
// Element is my HTMLMediaElement
element.srcObject = sd.stream;
// Play the sound
element.play();
element.setSinkId(deviceId).then(function() {
console.log('Set deviceId('+deviceId+') in the selected audio element');
});
this is most likely caused by how Chrome renders audio. See here for a description which also suggests using webaudio to workaround the problem.
adapter.js can not fix this.

WebRTC mix local and remote audio steams and record

So far i've found a way only to record either local or remote using MediaRecorder API but is it possible to mix and record both steams and get a blob?
Please note its audio steam only and i don't want to mix/record in server side.
I've a RTCPeerConnection as pc.
var local_stream = pc.getLocalStreams()[0];
var remote_stream = pc.getRemoteStreams()[0];
var audioChunks = [];
var rec = new MediaRecorder(local_stream);
rec.ondataavailable = e => {
audioChunks.push(e.data);
if (rec.state == "inactive")
// Play audio using new blob
}
rec.start();
Even i tried adding multiple tracks in MediaStream API but it still gives only first track audio. Any help or insight 'd be appreciated!
The WebAudio API can do mixing for you. Consider this code if you want to record all the audio tracks in the array audioTracks:
const ac = new AudioContext();
// WebAudio MediaStream sources only use the first track.
const sources = audioTracks.map(t => ac.createMediaStreamSource(new MediaStream([t])));
// The destination will output one track of mixed audio.
const dest = ac.createMediaStreamDestination();
// Mixing
sources.forEach(s => s.connect(dest));
// Record 10s of mixed audio as an example
const recorder = new MediaRecorder(dest.stream);
recorder.start();
recorder.ondataavailable = e => console.log("Got data", e.data);
recorder.onstop = () => console.log("stopped");
setTimeout(() => recorder.stop(), 10000);