Olaf VS opus-recorder

Ah I see. I've used Olaf for that, maybe it will work for you? https://github.com/JorenSix/Olaf

In the end, I went with this library for now: https://github.com/chris-rudmin/opus-recorder

There are issues reported with the latest iOS, though.

// size of one wav in ms var PACKAGESIZE = 175; // offset proportion for delay from recders ( if .5 recoder2 starts at the midlle of recorder1) var OFFSETRATIO = 0.99; var BRIDGERATIO = 0.05; // audio streamer implementation using https://github.com/chris-rudmin/opus-recorder to record audio data and convert to real 16bit pcm mono wav file // sending wav to flask server using post via ajax blob post function screenLogger(text, data) { log.innerHTML += "\n" + text + " " + (data || ''); // console.log(text); } var recorder = new Recorder({ monitorGain: 0, recordingGain: 1, numberOfChannels: 1, wavBitDepth: 16, encoderPath: "../static/dist/waveWorker.min.js" }); // function startRecording(){recorder.start();console.log("started recording");} document.getElementById("startRecording").addEventListener("click", function(){recorder.start();console.log("start");}); //#region recorder1 recorder.onstart = function(){ screenLogger('Recorder is started'); setTimeout(function(){recorder.stop();},PACKAGESIZE); }; recorder.onstop = function(){ screenLogger('Recorder is stopped'); recorder.start(); }; recorder.onstreamerror = function(e){ screenLogger('Error encountered: ' + e.message ); }; recorder.ondataavailable = function( typedArray ){ console.log(recorder.encodedSamplePosition); console.log("data available"); var dataBlob = new Blob( [typedArray], { type: 'audio/wav' } ); var form = new FormData(); form.append('file', dataBlob, "fileName"); form.append('title', "fileName2"); $.ajax({ type: 'POST', url: 'http://127.0.0.1:5000/send', crossDomain: true, data: form, cache: false, processData: false, contentType: false }).done(function(data,status) { console.log(data,status); screenLogger("result:",data); }); var fileName = new Date().toISOString() + ".wav"; var url = URL.createObjectURL( dataBlob ); var audio = document.createElement('audio'); audio.controls = true; audio.src = url; var link = document.createElement('a'); link.href = url; link.download = fileName; link.innerHTML = link.download; var li = document.createElement('li'); li.appendChild(link); li.appendChild(audio); recordingslist.appendChild(li); }; //#endregion //#region recoder2 var recorder2 = new Recorder({ monitorGain: 0, recordingGain: 1, numberOfChannels: 1, wavBitDepth: 16, encoderPath: "../static/dist/waveWorker.min.js" }); recorder2.onstart = function(){ screenLogger('Recorder 2 is started'); setTimeout(function(){recorder2.stop();},PACKAGESIZE*BRIDGERATIO); }; recorder2.onstop = function(){ screenLogger('Recorder 2 is stopped'); recorder2.start(); }; recorder2.onstreamerror = function(e){ screenLogger('Error encountered: ' + e.message ); }; recorder2.ondataavailable = function( typedArray ){ console.log("data available 2 "); var dataBlob = new Blob( [typedArray], { type: 'audio/wav' } ); var form = new FormData(); form.append('file', dataBlob, "fileName"); form.append('title', "fileName2"); $.ajax({ type: 'POST', url: 'http://127.0.0.1:5000/send', crossDomain: true, data: form, cache: false, processData: false, contentType: false }).done(function(data,status) { console.log(data,status); screenLogger("result:",data); }); var fileName = new Date().toISOString() + ".wav"; var url = URL.createObjectURL( dataBlob ); var audio = document.createElement('audio'); audio.controls = true; audio.src = url; var link = document.createElement('a'); link.href = url; link.download = fileName; link.innerHTML = link.download; var li = document.createElement('li'); li.appendChild(link); li.appendChild(audio); recordingslist.appendChild(li); }; //#endregion