[mirotalksfu] - add chat speech recognition

public/js/SpeechRec.js

@@ -0,0 +1,44 @@
+let isWebkitSpeechRecognitionSupported = false;
+let recognition;
+
+if ('webkitSpeechRecognition' in window) {
+    recognition = new webkitSpeechRecognition();
+
+    recognition.maxAlternatives = 1;
+    recognition.continuous = true;
+
+    recognition.onstart = function () {
+        console.log('Start speech recognition');
+        hide(chatSpeechStartButton);
+        show(chatSpeechStopButton);
+    };
+
+    recognition.onresult = (e) => {
+        let current = e.resultIndex;
+        let transcript = e.results[current][0].transcript;
+        chatMessage.value = transcript;
+    };
+
+    recognition.onerror = function (event) {
+        console.warn('Speech recognition error', event.error);
+    };
+
+    recognition.onend = function () {
+        console.log('Stop speech recognition');
+        show(chatSpeechStartButton);
+        hide(chatSpeechStopButton);
+    };
+
+    isWebkitSpeechRecognitionSupported = true;
+    console.info('Browser supports webkitSpeechRecognition');
+} else {
+    console.warn('This browser not supports webkitSpeechRecognition');
+}
+
+function startSpeech(action) {
+    if (action) {
+        recognition.start();
+    } else {
+        recognition.stop();
+    }
+}