added fingerprint lib

web/nfc-theme/static/code/generateTheAudioPrints.js

@@ -0,0 +1,76 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.generateTheAudioFingerPrint = void 0;
+//  ref = https://github.com/rickmacgillis/audio-fingerprint/blob/master/audio-fingerprinting.js
+// @ts-nocheck
+exports.generateTheAudioFingerPrint = (function () {
+    var context = null;
+    var currentTime = null;
+    var oscillator = null;
+    var compressor = null;
+    var fingerprint = null;
+    var callback = null;
+    function run(cb, debug = false) {
+        callback = cb;
+        try {
+            setup();
+            oscillator.connect(compressor);
+            compressor.connect(context.destination);
+            oscillator.start(0);
+            context.startRendering();
+            context.oncomplete = onComplete;
+        }
+        catch (e) {
+            if (debug) {
+                throw e;
+            }
+        }
+    }
+    function setup() {
+        setContext();
+        currentTime = context.currentTime;
+        setOscillator();
+        setCompressor();
+    }
+    function setContext() {
+        var audioContext = window.OfflineAudioContext || window.webkitOfflineAudioContext;
+        context = new audioContext(1, 44100, 44100);
+    }
+    function setOscillator() {
+        oscillator = context.createOscillator();
+        oscillator.type = "triangle";
+        oscillator.frequency.setValueAtTime(10000, currentTime);
+    }
+    function setCompressor() {
+        compressor = context.createDynamicsCompressor();
+        setCompressorValueIfDefined('threshold', -50);
+        setCompressorValueIfDefined('knee', 40);
+        setCompressorValueIfDefined('ratio', 12);
+        setCompressorValueIfDefined('reduction', -20);
+        setCompressorValueIfDefined('attack', 0);
+        setCompressorValueIfDefined('release', .25);
+    }
+    function setCompressorValueIfDefined(item, value) {
+        if (compressor[item] !== undefined && typeof compressor[item].setValueAtTime === 'function') {
+            compressor[item].setValueAtTime(value, context.currentTime);
+        }
+    }
+    function onComplete(event) {
+        generateFingerprints(event);
+        compressor.disconnect();
+    }
+    function generateFingerprints(event) {
+        var output = null;
+        for (var i = 4500; 5e3 > i; i++) {
+            var channelData = event.renderedBuffer.getChannelData(0)[i];
+            output += Math.abs(channelData);
+        }
+        fingerprint = output.toString();
+        if (typeof callback === 'function') {
+            return callback(fingerprint);
+        }
+    }
+    return {
+        run: run
+    };
+})();