Support recognition from real-time recordings.

This commit is contained in:
Fangjun Kuang 2022-05-07 19:53:42 +08:00
parent 30b2626172
commit 298b52ffa3
3 changed files with 210 additions and 59 deletions

View File

@ -18,7 +18,7 @@
</head>
<body>
<body onload="initWebSocket()">
<div id="nav"></div>
<script>
$(function(){
@ -43,6 +43,13 @@
</div>
</div>
<div class="mb-3">
<label for="results" class="form-label">Recognition results</label>
<textarea class="form-control" id="results" rows="8"></textarea>
</div>
<button class="btn btn-primary btn-block" id="clear">Clear results</button>
<section flex="1" overflow="auto" id="sound-clips">
</section>

View File

@ -1,69 +1,140 @@
// see https://mdn.github.io/web-dictaphone/scripts/app.js
// and https://gist.github.com/meziantou/edb7217fddfbb70e899e
const record = document.getElementById('record');
const stop = document.getElementById('stop');
var socket;
function initWebSocket() {
socket = new WebSocket("ws://localhost:6008/");
// Connection opened
socket.addEventListener('open', function(event) {
console.log('connected');
document.getElementById('record').disabled = false;
});
// Connection closed
socket.addEventListener('close', function(event) {
console.log('disconnected');
document.getElementById('record').disabled = true;
initWebSocket();
});
// Listen for messages
socket.addEventListener('message', function(event) {
document.getElementById('results').innerHTML = event.data;
console.log('Received message: ', event.data);
});
}
const recordBtn = document.getElementById('record');
const stopBtn = document.getElementById('stop');
const clearBtn = document.getElementById('clear');
const soundClips = document.getElementById('sound-clips');
const canvas = document.getElementById('canvas');
const mainSection = document.querySelector('.container');
soundClips.innerHTML = "hello";
stop.disabled = true;
stopBtn.disabled = true;
let audioCtx;
const canvasCtx = canvas.getContext("2d");
let mediaStream;
let analyser;
let sampleRate;
let expectedSampleRate = 16000;
let recordSampleRate; // the sampleRate of the microphone
let recorder = null; // the microphone
let leftchannel = []; // TODO: Use a single channel
let recordingLength = 0; // number of samples so far
clearBtn.onclick =
function() { document.getElementById('results').innerHTML = ''; };
// copied/modified from https://mdn.github.io/web-dictaphone/
// and
// https://gist.github.com/meziantou/edb7217fddfbb70e899e
if (navigator.mediaDevices.getUserMedia) {
console.log('getUserMedia supported.');
// see https://w3c.github.io/mediacapture-main/#dom-mediadevices-getusermedia
const constraints = {
// does not work
// audio : {sampleRate : 16000, sampleSize : 16, channelCount : 1}
audio : true,
};
let chunks = [];
const constraints = {audio : true};
let onSuccess = function(stream) {
var settings = stream.getAudioTracks()[0].getSettings();
sampleRate = settings.sampleRate;
console.log(settings);
console.log('sample rate ' + settings.sampleRate);
console.log('channel count ' + settings.channelCount);
console.log('sample size ' + settings.sampleSize);
const mediaRecorder = new MediaRecorder(stream);
console.log('mime type ' + mediaRecorder.mimeType);
console.log('audio bits per second ' + mediaRecorder.audioBitsPerSecond);
console.log(mediaRecorder)
if (!audioCtx) {
audioCtx = new AudioContext();
}
console.log(audioCtx);
recordSampleRate = audioCtx.sampleRate;
console.log('sample rate ' + recordSampleRate);
// creates an audio node from the microphone incoming stream
mediaStream = audioCtx.createMediaStreamSource(stream);
console.log(mediaStream);
// https://developer.mozilla.org/en-US/docs/Web/API/AudioContext/createScriptProcessor
// bufferSize: the onaudioprocess event is called when the buffer is full
var bufferSize = 2048;
var numberOfInputChannels = 2;
var numberOfOutputChannels = 2;
if (audioCtx.createScriptProcessor) {
recorder = audioCtx.createScriptProcessor(
bufferSize, numberOfInputChannels, numberOfOutputChannels);
} else {
recorder = audioCtx.createJavaScriptNode(
bufferSize, numberOfInputChannels, numberOfOutputChannels);
}
console.log(recorder);
recorder.onaudioprocess = function(e) {
let samples = new Float32Array(e.inputBuffer.getChannelData(0))
samples = downsampleBuffer(samples, expectedSampleRate);
let buf = new Int16Array(samples.length);
for (var i = 0; i < samples.length; ++i) {
let s = samples[i];
if (s >= 1)
s = 1;
else if (s <= -1)
s = -1;
buf[i] = s * 32767;
}
socket.send(buf);
leftchannel.push(buf);
recordingLength += bufferSize;
console.log(recordingLength);
};
visualize(stream);
mediaStream.connect(analyser);
recordBtn.onclick = function() {
mediaStream.connect(recorder);
mediaStream.connect(analyser);
recorder.connect(audioCtx.destination);
record.onclick = function() {
mediaRecorder.start(10); // 10ms period to send data
console.log(mediaRecorder.state);
console.log("recorder started");
record.style.background = "red";
recordBtn.style.background = "red";
stop.disabled = false;
record.disabled = true;
stopBtn.disabled = false;
recordBtn.disabled = true;
};
stop.onclick = function() {
mediaRecorder.stop();
console.log(mediaRecorder.state);
stopBtn.onclick = function() {
console.log("recorder stopped");
record.style.background = "";
record.style.color = "";
socket.close();
// stopBtn recording
recorder.disconnect(audioCtx.destination);
mediaStream.disconnect(recorder);
mediaStream.disconnect(analyser);
recordBtn.style.background = "";
recordBtn.style.color = "";
// mediaRecorder.requestData();
stop.disabled = true;
record.disabled = false;
};
mediaRecorder.onstop = function(e) {
console.log("data available after MediaRecorder.stop() called.");
stopBtn.disabled = true;
recordBtn.disabled = false;
const clipName =
prompt('Enter a name for your sound clip?', 'My unnamed clip');
@ -72,7 +143,6 @@ if (navigator.mediaDevices.getUserMedia) {
const clipLabel = document.createElement('p');
const audio = document.createElement('audio');
const deleteButton = document.createElement('button');
clipContainer.classList.add('clip');
audio.setAttribute('controls', '');
deleteButton.textContent = 'Delete';
@ -85,24 +155,26 @@ if (navigator.mediaDevices.getUserMedia) {
}
clipContainer.appendChild(audio);
clipContainer.appendChild(clipLabel);
clipContainer.appendChild(deleteButton);
soundClips.appendChild(clipContainer);
audio.controls = true;
const blob = new Blob(chunks, {'type' : 'audio/ogg; codecs=opus'});
chunks = [];
let samples = flatten(leftchannel);
const blob = toWav(samples);
leftchannel = [];
const audioURL = window.URL.createObjectURL(blob);
audio.src = audioURL;
console.log("recorder stopped");
deleteButton.onclick =
function(e) {
deleteButton.onclick = function(e) {
let evtTgt = e.target;
evtTgt.parentNode.parentNode.removeChild(evtTgt.parentNode);
}
};
clipLabel.onclick = function() {
clipLabel.onclick = function() {
const existingName = clipLabel.textContent;
const newClipName = prompt('Enter a new name for your sound clip?');
if (newClipName === null) {
@ -110,23 +182,17 @@ if (navigator.mediaDevices.getUserMedia) {
} else {
clipLabel.textContent = newClipName;
}
}
};
};
mediaRecorder.ondataavailable = function(e) {
console.log('size ' + e.data.size);
console.log(e.data);
chunks.push(e.data);
}
};
let onError = function(
err) { console.log('The following error occured: ' + err); };
navigator.mediaDevices.getUserMedia(constraints).then(onSuccess, onError);
} else {
console.log('getUserMedia not supported on your browser!');
alert('getUserMedia not supported on your browser!');
}
function visualize(stream) {
@ -136,12 +202,14 @@ function visualize(stream) {
const source = audioCtx.createMediaStreamSource(stream);
const analyser = audioCtx.createAnalyser();
analyser.fftSize = 2048;
if (!analyser) {
analyser = audioCtx.createAnalyser();
analyser.fftSize = 2048;
}
const bufferLength = analyser.frequencyBinCount;
const dataArray = new Uint8Array(bufferLength);
source.connect(analyser);
// source.connect(analyser);
// analyser.connect(audioCtx.destination);
draw()
@ -187,3 +255,79 @@ function visualize(stream) {
window.onresize = function() { canvas.width = mainSection.offsetWidth; };
window.onresize();
// this function is copied/modified from
// https://gist.github.com/meziantou/edb7217fddfbb70e899e
function flatten(listOfSamples) {
let n = 0;
for (let i = 0; i < listOfSamples.length; ++i) {
n += listOfSamples[i].length;
}
let ans = new Int16Array(n);
let offset = 0;
for (let i = 0; i < listOfSamples.length; ++i) {
ans.set(listOfSamples[i], offset);
offset += listOfSamples[i].length;
}
return ans;
}
// this function is copied/modified from
// https://gist.github.com/meziantou/edb7217fddfbb70e899e
function toWav(samples) {
let buf = new ArrayBuffer(44 + samples.length * 2);
var view = new DataView(buf);
// http://soundfile.sapp.org/doc/WaveFormat/
// F F I R
view.setUint32(0, 0x46464952, true); // chunkID
view.setUint32(4, 36 + samples.length * 2, true); // chunkSize
// E V A W
view.setUint32(8, 0x45564157, true); // format
//
// t m f
view.setUint32(12, 0x20746d66, true); // subchunk1ID
view.setUint32(16, 16, true); // subchunk1Size, 16 for PCM
view.setUint32(20, 1, true); // audioFormat, 1 for PCM
view.setUint16(22, 1, true); // numChannels: 1 channel
view.setUint32(24, expectedSampleRate, true); // sampleRate
view.setUint32(28, expectedSampleRate * 2, true); // byteRate
view.setUint16(32, 2, true); // blockAlign
view.setUint16(34, 16, true); // bitsPerSample
view.setUint32(36, 0x61746164, true); // Subchunk2ID
view.setUint32(40, samples.length * 2, true); // subchunk2Size
let offset = 44;
for (let i = 0; i < samples.length; ++i) {
view.setInt16(offset, samples[i], true);
offset += 2;
}
return new Blob([ view ], {type : 'audio/wav'});
}
// this function is copied from
// https://github.com/awslabs/aws-lex-browser-audio-capture/blob/master/lib/worker.js#L46
function downsampleBuffer(buffer, exportSampleRate) {
if (exportSampleRate === recordSampleRate) {
return buffer;
}
var sampleRateRatio = recordSampleRate / exportSampleRate;
var newLength = Math.round(buffer.length / sampleRateRatio);
var result = new Float32Array(newLength);
var offsetResult = 0;
var offsetBuffer = 0;
while (offsetResult < result.length) {
var nextOffsetBuffer = Math.round((offsetResult + 1) * sampleRateRatio);
var accum = 0, count = 0;
for (var i = offsetBuffer; i < nextOffsetBuffer && i < buffer.length; i++) {
accum += buffer[i];
count++;
}
result[offsetResult] = accum / count;
offsetResult++;
offsetBuffer = nextOffsetBuffer;
}
return result;
};

View File

@ -35,7 +35,7 @@
<div class="mb-3">
<label for="results" class="form-label">Recognition results</label>
<textarea class="form-control" id="results" rows="3"></textarea>
<textarea class="form-control" id="results" rows="8"></textarea>
</div>
</form>