1082 lines
37 KiB
JavaScript
1082 lines
37 KiB
JavaScript
var audioContext;
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var sendButton;
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var textToSend;
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var isListeningCheckbox;
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var samplesPerBitLabel;
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var microphoneStream;
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var microphoneNode;
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var analyser;
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var receivedDataTextarea;
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var sentDataTextArea;
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var receivedGraph;
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var receivedData = [];
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var MAX_DATA = 300;
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var pauseTimeoutId;
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var sampleIntervalId;
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var TEXT_TO_SEND = "U";
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var MAX_BITS_DISPLAYED_ON_GRAPH = 115;
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var SEGMENT_DURATION = 30;
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var AMPLITUDE_THRESHOLD_PERCENT = .75;
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var AMPLITUDE_THRESHOLD = 160;
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var MINIMUM_FREQUENCY = 308;
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var MAXIMUM_FREQUENCY = 3400;
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var LAST_SEGMENT_PERCENT = 0.6;
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var FFT_SIZE_POWER = 10;
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var FREQUENCY_RESOLUTION_MULTIPLIER = 2;
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var SMOOTHING_TIME_CONSTANT = 0;
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var HAMMING_ERROR_CORRECTION = true;
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var SAMPLE_DELAY_MS = 1;
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var frequencyOverTime = [];
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var bitStart = [];
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var samplesPerBit = [];
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var bitSampleCount = 0;
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var PAUSE = false;
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var PAUSE_AFTER_END = true;
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var PACKET_SIZE_BITS = 8;
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var EXPECTED_ENCODED_BITS = [];
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var EXPECTED_BITS = [];
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var EXPECTED_TEXT = '';
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const packetReceivedBits = [];
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const packetDecodedBits = [];
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let packetDataByteCount = -1;
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function handleWindowLoad() {
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const printable = "abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890`-=~!@#$%^&*()_+[]\\{}|;':\",./<>?";
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TEXT_TO_SEND = new Array(128).fill(0).map(() => printable[Math.floor(Math.random() * printable.length)]).join('');
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// grab dom elements
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sendButton = document.getElementById('send-button');
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isListeningCheckbox = document.getElementById('is-listening-checkbox');
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receivedDataTextarea = document.getElementById('received-data');
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receivedGraph = document.getElementById('received-graph');
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textToSend = document.getElementById('text-to-send');
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textToSend.value = TEXT_TO_SEND;
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sentDataTextArea = document.getElementById('sent-data');
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samplesPerBitLabel = document.getElementById('samples-per-bit');
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document.getElementById('pause-after-end').checked = PAUSE_AFTER_END;
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document.getElementById('error-correction-hamming').checked = HAMMING_ERROR_CORRECTION;
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document.getElementById('error-correction-hamming').addEventListener('change', event => {
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HAMMING_ERROR_CORRECTION = event.target.checked;
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showSpeed();
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})
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document.getElementById('pause-after-end').addEventListener('change', event => {
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PAUSE_AFTER_END = event.target.checked;
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if(!PAUSE_AFTER_END) resumeGraph();
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})
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document.getElementById('frequency-resolution-multiplier').value = FREQUENCY_RESOLUTION_MULTIPLIER;
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document.getElementById('frequency-resolution-multiplier').addEventListener('input', event => {
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FREQUENCY_RESOLUTION_MULTIPLIER = parseInt(event.target.value);
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showSpeed();
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})
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document.getElementById('bit-duration-text').addEventListener('input', (event) => {
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SEGMENT_DURATION = parseInt(event.target.value);
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bitSampleCount = 0;
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samplesPerBit.length = 0;
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showSpeed();
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});
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document.getElementById('max-bits-displayed-on-graph').value= MAX_BITS_DISPLAYED_ON_GRAPH;
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document.getElementById('max-bits-displayed-on-graph').addEventListener('input', (event) => {
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MAX_BITS_DISPLAYED_ON_GRAPH = parseInt(event.target.value);
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})
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document.getElementById('bit-duration-text').value = SEGMENT_DURATION;
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document.getElementById('amplitude-threshold-text').value = Math.floor(AMPLITUDE_THRESHOLD_PERCENT * 100);
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AMPLITUDE_THRESHOLD = Math.floor(AMPLITUDE_THRESHOLD_PERCENT * 255);
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document.getElementById('maximum-frequency').value = MAXIMUM_FREQUENCY;
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document.getElementById('minimum-frequency').value = MINIMUM_FREQUENCY;
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document.getElementById('last-bit-percent').value = Math.floor(LAST_SEGMENT_PERCENT * 100);
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document.getElementById('fft-size-power-text').value = FFT_SIZE_POWER;
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document.getElementById('smoothing-time-constant-text').value = SMOOTHING_TIME_CONSTANT.toFixed(2);
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document.getElementById('amplitude-threshold-text').addEventListener('input', (event) => {
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AMPLITUDE_THRESHOLD_PERCENT = parseInt(event.target.value) / 100;
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AMPLITUDE_THRESHOLD = Math.floor(AMPLITUDE_THRESHOLD_PERCENT * 255);
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});
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document.getElementById('maximum-frequency').addEventListener('input', (event) => {
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MAXIMUM_FREQUENCY = parseInt(event.target.value);
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showSpeed();
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});
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document.getElementById('minimum-frequency').addEventListener('input', (event) => {
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MINIMUM_FREQUENCY = parseInt(event.target.value);
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showSpeed();
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});
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document.getElementById('last-bit-percent').addEventListener('input', (event) => {
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LAST_SEGMENT_PERCENT = parseInt(event.target.value) / 100;
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});
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document.getElementById('fft-size-power-text').addEventListener('input', (event) => {
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FFT_SIZE_POWER = parseInt(event.target.value);
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if(analyser) analyser.fftSize = 2 ** FFT_SIZE_POWER;
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updateFrequencyResolution();
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resetGraphData();
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});
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updateFrequencyResolution();
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document.getElementById('smoothing-time-constant-text').addEventListener('input', event => {
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SMOOTHING_TIME_CONSTANT = parseFloat(event.target.value);
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if(analyser) analyser.smoothingTimeConstant = SMOOTHING_TIME_CONSTANT;
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});
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document.getElementById('audio-context-sample-rate').innerText = getAudioContext().sampleRate.toLocaleString();
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// wire up events
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sendButton.addEventListener('click', handleSendButtonClick);
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isListeningCheckbox.addEventListener('click', handleListeningCheckbox);
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textToSend.addEventListener('input', handleTextToSendInput);
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handleTextToSendInput();
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showSpeed();
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}
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function handleTextToSendInput() {
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const text = textToSend.value;
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const dataByteCount = text.length;
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const dataBitCount = dataByteCount * 8;
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const nibblesToEncode = HAMMING_ERROR_CORRECTION ? Math.ceil((dataBitCount + PACKET_SIZE_BITS) / 4) : 0;
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const errorCorrectionBits = nibblesToEncode * 3;
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const totalBits = errorCorrectionBits + dataBitCount + PACKET_SIZE_BITS;
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const totalBytes = Math.ceil(totalBits / 8);
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const channelCount = getChannels().length;
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const segmentCount = Math.ceil(totalBits / channelCount);
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const totalDuration = ((segmentCount * SEGMENT_DURATION) / 1000);
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document.getElementById('error-correction-bits').innerText = errorCorrectionBits.toLocaleString();
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document.getElementById('data-bytes-to-send').innerText = dataByteCount.toLocaleString();
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document.getElementById('data-bits-to-send').innerText = dataBitCount.toLocaleString();
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document.getElementById('total-bytes-to-send').innerText = totalBytes.toLocaleString();
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document.getElementById('total-bits-to-send').innerText = totalBits.toLocaleString();
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document.getElementById('duration-to-send').innerText = totalDuration.toLocaleString();
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document.getElementById('packet-send-channel-count').innerText = channelCount.toLocaleString();
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document.getElementById('packet-send-segment-count').innerText = segmentCount.toLocaleString();
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document.getElementById('packet-send-segment-duration').innerText = (SEGMENT_DURATION / 1000).toLocaleString();
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document.getElementById('data-size-header-bits').innerText = PACKET_SIZE_BITS.toLocaleString();
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}
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function updateFrequencyResolution() {
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const sampleRate = getAudioContext().sampleRate;
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const fftSize = 2 ** FFT_SIZE_POWER;
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const frequencyResolution = sampleRate / fftSize;
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const frequencyCount = (sampleRate/2) / frequencyResolution;
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document.getElementById('frequency-resolution').innerText = frequencyResolution.toFixed(2);
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document.getElementById('frequency-count').innerText = frequencyCount.toFixed(2);
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showSpeed();
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}
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function showSpeed() {
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const segmentsPerSecond = 1000 / SEGMENT_DURATION;
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const channels = getChannels();
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const bitsPerSegment = channels.length;
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const baud = bitsPerSegment * segmentsPerSecond;
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const bytes = baud / 8;
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document.getElementById('durations-per-second').innerText = segmentsPerSecond.toFixed(2);
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document.getElementById('bits-per-duration').innerText = bitsPerSegment;
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document.getElementById('data-transfer-speed-bits-per-second').innerText = baud.toFixed(2);
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document.getElementById('data-transfer-speed-bytes-per-second').innerText = bytes.toFixed(2);
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if(HAMMING_ERROR_CORRECTION) {
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const effectiveBaud = baud * 4 / 7;
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const effectiveBytes = effectiveBaud / 8;
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document.getElementById('effective-speed-bits-per-second').innerText = effectiveBaud.toFixed(2);
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document.getElementById('effective-speed-bytes-per-second').innerText = effectiveBytes.toFixed(2);
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} else {
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const effectiveBaud = baud;
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const effectiveBytes = effectiveBaud / 8;
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document.getElementById('effective-speed-bits-per-second').innerText = effectiveBaud.toFixed(2);
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document.getElementById('effective-speed-bytes-per-second').innerText = effectiveBytes.toFixed(2);
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}
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const channelList = document.getElementById('channel-list');
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channelList.innerHTML = "";
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channels.forEach(([low, high]) => {
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const li = document.createElement('li');
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li.textContent = `Low: ${low} Hz High: ${high} Hz`;
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channelList.appendChild(li);
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})
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handleTextToSendInput();
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drawChannels();
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}
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function drawChannels() {
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const sampleRate = getAudioContext().sampleRate;
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const fftSize = 2 ** FFT_SIZE_POWER;
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const frequencyResolution = sampleRate / fftSize;
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//const frequencyCount = (sampleRate/2) / frequencyResolution;
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const channels = getChannels();
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const channelCount = channels.length;
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const canvas = document.getElementById('channel-frequency-graph');
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const ctx = canvas.getContext('2d');
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const {height, width} = canvas;
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const channelHeight = height / channelCount;
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const bandHeight = channelHeight / 2;
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const nyquistFrequency = audioContext.sampleRate / 2;
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const frequencySegments = Math.floor(nyquistFrequency / frequencyResolution);
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for(let i = 0; i < channelCount; i++) {//xxx
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const [low, high] = channels[i];
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let top = channelHeight * i;
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ctx.fillStyle = 'black';
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ctx.fillRect(0, top, width, bandHeight);
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ctx.fillStyle = 'white';
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ctx.fillRect(0, top + bandHeight, width, bandHeight);
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const lowX = percentInFrequency(low, frequencyResolution) * width;
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ctx.lineWidth = 2;
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ctx.strokeStyle = 'blue';
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ctx.beginPath();
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ctx.moveTo(lowX, top);
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ctx.lineTo(lowX, top + bandHeight);
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ctx.stroke();
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const highX = percentInFrequency(high, frequencyResolution) * width;
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ctx.lineWidth = 2;
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ctx.strokeStyle = 'blue';
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ctx.beginPath();
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ctx.moveTo(highX, top + bandHeight);
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ctx.lineTo(highX, top + (bandHeight * 2));
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ctx.stroke();
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}
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/*
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const binWidth = (1 / frequencySegments) * width;
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for(let x = 0; x < width; x+= binWidth * 2) {
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console.log(x);
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ctx.fillStyle = 'rgba(0, 0, 0, 0.25)';
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ctx.fillRect(x, 0, binWidth, height);
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}
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*/
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}
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function percentInFrequency(hz, frequencyResolution) {
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const index = Math.floor(hz/frequencyResolution);
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const startHz = index * frequencyResolution;
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const hzInSegement = hz - startHz;
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const percent = hzInSegement / frequencyResolution;
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return percent;
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}
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function nibbleToHamming(nibble) {
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if(nibble.length !== 4) return [];
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return [
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nibble[0] ^ nibble[1] ^ nibble[3],
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nibble[0] ^ nibble[2] ^ nibble[3],
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nibble[0],
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nibble[1] ^ nibble[2] ^ nibble[3],
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nibble[1],
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nibble[2],
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nibble[3]
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]
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}
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function hammingToNibble(hamming) {
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if(hamming.length !== 7) return [];
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const error_1 = hamming[0] ^ hamming[2] ^ hamming[4] ^ hamming[6];
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const error_2 = hamming[1] ^ hamming[2] ^ hamming[5] ^ hamming[6];
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const error_3 = hamming[3] ^ hamming[4] ^ hamming[5] ^ hamming[6];
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let error = (error_3 << 2) | (error_2 << 1) | error_1;
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if(error !== 0) {
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// don't mutate the array
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hamming = hamming.slice();
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hamming[error - 1] ^= 1; // flip
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}
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return [
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hamming[2],
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hamming[4],
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hamming[5],
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hamming[6]
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];
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}
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function getFrequency(bit) {
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return bit ? MAXIMUM_FREQUENCY : MINIMUM_FREQUENCY;
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}
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function getChannels() {
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var audioContext = getAudioContext();
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const sampleRate = audioContext.sampleRate;
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const fftSize = 2 ** FFT_SIZE_POWER;
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const frequencyResolution = sampleRate / fftSize;
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const channels = [];
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const pairStep = frequencyResolution * 2 * FREQUENCY_RESOLUTION_MULTIPLIER;
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for(let hz = MINIMUM_FREQUENCY; hz < MAXIMUM_FREQUENCY; hz+= pairStep) {
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const low = Math.floor(hz);
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const high = Math.floor(hz + frequencyResolution * FREQUENCY_RESOLUTION_MULTIPLIER);
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if(low < MINIMUM_FREQUENCY) continue;
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if(high > MAXIMUM_FREQUENCY) continue;
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channels.push([low, high]);
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}
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return channels;
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}
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function logSent(text) {
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// display what is being sent
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sentDataTextArea.value += text + '\n';
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sentDataTextArea.scrollTop = sentDataTextArea.scrollHeight;
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}
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function sendBits(bits) {
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const byteCount = bits.length / 8;
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if(bits.length === 0) {
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logSent('No bits to send!');
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return;
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} else if(bits.length % 8 !== 0 || bits.length === 0) {
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logSent('Bit count must be divisible by 8.');
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return;
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} else if(byteCount > (1 << PACKET_SIZE_BITS)) {
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logSent(`Can not transfer more than ${(1 << PACKET_SIZE_BITS)} bytes.`);
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return;
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}
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const packetLength = ((byteCount - 1) >>> 0)
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.toString(2)
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.padStart(PACKET_SIZE_BITS, '0')
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.split('')
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.map(Number);
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bits.unshift(...packetLength);
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EXPECTED_BITS = bits.slice();
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document.getElementById('sent-data').value = bits.reduce(bitReducer, '');
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if(HAMMING_ERROR_CORRECTION) {
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const encodedBits = [];
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for(let i = 0; i < bits.length; i+= 4) {
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const nibble = bits.slice(i, i + 4);
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while(nibble.length < 4) nibble.push(0);
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encodedBits.push(...nibbleToHamming(bits.slice(i, i + 4)));
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}
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document.getElementById('encoded-data').value = encodedBits.reduce(bitReducer, '');
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bits = encodedBits;
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} else {
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document.getElementById('encoded-data').value = bits.reduce(bitReducer, '');
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}
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EXPECTED_ENCODED_BITS = bits.slice();
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var audioContext = getAudioContext();
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const channels = getChannels();
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const oscillators = [];
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const channelCount = channels.length;
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const currentTime = audioContext.currentTime + 0.1;
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// create our oscillators
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for(let i = 0; i < channelCount; i++) {
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var oscillator = audioContext.createOscillator();
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oscillator.connect(audioContext.destination);
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oscillators.push(oscillator);
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}
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// change our channel frequencies for the bit
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for(let i = 0; i < bits.length; i++) {
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const isHigh = bits[i];
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const channel = i % channelCount;
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const segment = Math.floor(i / channelCount);
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var offset = ((segment * SEGMENT_DURATION)/1000);
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oscillators[channel].frequency.setValueAtTime(
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channels[channel][isHigh ? 1 : 0],
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currentTime + offset
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);
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}
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// start sending our signal
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oscillators.forEach(o => o.start(currentTime));
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// silence oscillators when done
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for(let i = bits.length; i < bits.length + channelCount; i++) {
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const channel = i % channelCount;
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const segment = Math.floor(i / channelCount);
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const offset = ((segment * SEGMENT_DURATION) / 1000);
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oscillators[channel].stop(currentTime + offset);
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}
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// start the graph moving again
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resumeGraph();
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}
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function stopGraph() {
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PAUSE = true;
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if(sampleIntervalId) {
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window.clearInterval(sampleIntervalId);
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sampleIntervalId = undefined;
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}
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}
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function resumeGraph() {
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if(isListeningCheckbox.checked) {
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if(PAUSE) {
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PAUSE = false;
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sampleIntervalId = window.setInterval(collectSample, SAMPLE_DELAY_MS);
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resetGraphData();
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requestAnimationFrame(drawFrequencyData);
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} else {
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PAUSE = false;
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}
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} else {
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PAUSE = false;
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}
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}
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function getInteger(start, end, samples) {
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let value = 0;
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let valueIndex = 0;
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for(let i = 0; i < samples.length; i++) {
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for(let j = 0; j < samples[i].pairs.length; j++) {
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if(b >= start) {
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value += getBit(samples[i].pairs[j]) << valueIndex++;
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if(b >= end) return bits;
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}
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b++;
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}
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}
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return bits;
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}
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function collectSample() {
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const time = performance.now();
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const frequencies = new Uint8Array(analyser.frequencyBinCount);
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const length = audioContext.sampleRate / analyser.fftSize;
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let processSegment = false;
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const {
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hasSignal: hadPriorSignal,
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streamStarted: initialStreamStart = -1,
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streamEnded: priorStreamEnded = -1,
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segmentIndex: priorSegmentIndex = -1
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} = frequencyOverTime[0] ?? {}
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analyser.getByteFrequencyData(frequencies);
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const data = {
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time,
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frequencies: [...frequencies],
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length,
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streamEnded: priorStreamEnded
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};
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let hasSignal = false;
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data.pairs = getChannels().map(([low, high], i) => {
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const lowAmp = frequencies[Math.round(low / length)];
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const highAmp = frequencies[Math.round(high / length)];
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const isLow = lowAmp > AMPLITUDE_THRESHOLD;
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const isHigh = highAmp > AMPLITUDE_THRESHOLD;
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if(isLow || isHigh ) hasSignal = true;
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return {
|
|
channel: i,
|
|
lowHz: low,
|
|
highHz: high,
|
|
lowAmp,
|
|
highAmp,
|
|
isMissing: !(isHigh || isLow),
|
|
isHigh: (isHigh && !isLow) || highAmp > lowAmp
|
|
};
|
|
});
|
|
data.hasSignal = hasSignal;
|
|
if(hasSignal) {
|
|
if(hadPriorSignal) {
|
|
// continued bit stream
|
|
data.streamStarted = initialStreamStart;
|
|
|
|
// proposed end
|
|
data.streamEnded = priorStreamEnded;
|
|
} else {
|
|
// new bit stream
|
|
data.streamStarted = time;
|
|
// clear last packet
|
|
packetReceivedBits.length = 0;
|
|
packetDataByteCount = 0;
|
|
}
|
|
|
|
// number of bit in the stream
|
|
const segmentIndex = data.segmentIndex = Math.floor((time - data.streamStarted) / SEGMENT_DURATION);
|
|
if(priorSegmentIndex !== segmentIndex && priorSegmentIndex > -1) {
|
|
processSegment = true;
|
|
}
|
|
} else {
|
|
data.segmentIndex = -1;
|
|
if(hadPriorSignal) {
|
|
// just stopped
|
|
data.streamStarted = -1;
|
|
data.streamEnded = -1;
|
|
// update all prior values with stream end if they don't have one
|
|
frequencyOverTime
|
|
.filter(fov => fov.streamStarted === initialStreamStart)
|
|
.filter(fov => fov.streamEnded === -1)
|
|
.forEach(fov => {
|
|
fov.streamEnded === time
|
|
});
|
|
processSegment = true;
|
|
if(PAUSE_AFTER_END && !pauseTimeoutId) {
|
|
pauseTimeoutId = window.setTimeout(() => {
|
|
pauseTimeoutId = undefined;
|
|
if(PAUSE_AFTER_END) stopGraph();
|
|
}, SEGMENT_DURATION * 0.5);
|
|
}
|
|
} else {
|
|
// continued stopping (or never started)
|
|
data.streamEnded = -1;
|
|
}
|
|
}
|
|
frequencyOverTime.unshift(data);
|
|
if(processSegment) processSegmentReceived(initialStreamStart, priorSegmentIndex);
|
|
truncateGraphData();
|
|
}
|
|
|
|
function GET_SEGMENT_BITS(streamStarted, segmentIndex) {
|
|
const bits = frequencyOverTime.filter(f =>
|
|
f.segmentIndex === segmentIndex &&
|
|
f.streamStarted === streamStarted
|
|
);
|
|
const channelCount = frequencyOverTime[0].pairs.length;
|
|
const sums = new Array(channelCount).fill(0).map(() => ({
|
|
high: 0,
|
|
low: 0,
|
|
heard: 0
|
|
}));
|
|
bits.forEach(({pairs}) => {
|
|
pairs.forEach(({ highAmp, lowAmp, channel }) => {
|
|
sums[channel].high += highAmp;
|
|
sums[channel].low += lowAmp;
|
|
if(highAmp > AMPLITUDE_THRESHOLD || lowAmp > AMPLITUDE_THRESHOLD) {
|
|
sums[channel].heard++;
|
|
}
|
|
})
|
|
});
|
|
const bitValues = sums.map(({high, low}) => high >= low ? 1 : 0);
|
|
// cut off silent bits
|
|
// const lastHeard = sums.lastIndexOf(s => s.heard !== 0);
|
|
const lastHeard = sums.length -1;
|
|
return bitValues.slice(0, lastHeard + 1);
|
|
}
|
|
function processSegmentReceived(streamStarted, segmentIndex) {
|
|
const {
|
|
pairs: {
|
|
length: channelCount
|
|
}
|
|
} = frequencyOverTime[0];
|
|
// is our segment long enough?
|
|
|
|
const samples = frequencyOverTime.filter(
|
|
fot => fot.streamStarted === streamStarted &&
|
|
fot.segmentIndex === segmentIndex
|
|
);
|
|
if(samples.length <= 1) return; // too short
|
|
const sampleEnd = samples[0].time;
|
|
const sampleStart = samples[samples.length-1].time;
|
|
const sampleDuration = sampleEnd - sampleStart;
|
|
|
|
// not long enough to qualify as a segment
|
|
if((sampleDuration / SEGMENT_DURATION) < LAST_SEGMENT_PERCENT) return;
|
|
|
|
const bitValues = GET_SEGMENT_BITS(streamStarted, segmentIndex);
|
|
|
|
|
|
console.log("%s Received: %s from %s samples", segmentIndex, bitValues.join(''), samples.length);
|
|
packetReceivedBits.push(...bitValues);
|
|
|
|
const encodingRatio = HAMMING_ERROR_CORRECTION ? 7/4 : 1;
|
|
if(HAMMING_ERROR_CORRECTION) {
|
|
packetDecodedBits.length = 0;
|
|
for(let i = 0; i < packetReceivedBits.length; i += 7) {
|
|
const hamming = packetReceivedBits.slice(i, i + 7);
|
|
const nibble = hammingToNibble(hamming);
|
|
packetDecodedBits.push(...nibble);
|
|
}
|
|
} else {
|
|
packetDecodedBits.length = 0;
|
|
packetDecodedBits.push(...packetReceivedBits);
|
|
}
|
|
|
|
// Determine if we can identify the length of data comming
|
|
const encodedBitsNeededForDataLength = Math.ceil(Math.ceil(PACKET_SIZE_BITS / 4) * encodingRatio);
|
|
if(packetDecodedBits.length >= encodedBitsNeededForDataLength) {
|
|
// we can evaluate when we should know many bytes are comming
|
|
const dataLengthIndex = Math.floor(encodedBitsNeededForDataLength / channelCount);
|
|
// if(dataLengthIndex === segmentIndex) {
|
|
// we just got the bits we needed
|
|
packetDataByteCount = 1 + packetDecodedBits
|
|
.slice(0, PACKET_SIZE_BITS)
|
|
.reduce((value, bit) => (value << 1) | bit);
|
|
document.getElementById('decoded-byte-count').innerText = packetDataByteCount;
|
|
// let's get the end time
|
|
const totalBits = Math.ceil(((packetDataByteCount * 8) + PACKET_SIZE_BITS) * encodingRatio);
|
|
const segments = Math.ceil(totalBits / channelCount);
|
|
const duration = segments * SEGMENT_DURATION;
|
|
const streamEnded = streamStarted + duration;
|
|
// console.log({
|
|
// tenBitNum: packetDecodedBits
|
|
// .slice(0, PACKET_SIZE_BITS).join(''),
|
|
// packetDataByteCount,
|
|
// PACKET_SIZE_BITS,
|
|
// totalBits,
|
|
// segments,
|
|
// streamStarted,
|
|
// duration,
|
|
// streamEnded
|
|
// });
|
|
// update everyones proposed end time
|
|
frequencyOverTime
|
|
.filter(fot => fot.streamStarted === streamStarted)
|
|
.forEach(fot => {
|
|
fot.streamEnded = streamEnded
|
|
});
|
|
// }
|
|
// remove phantom bits
|
|
// const totalBits = Math.ceil(((packetDataByteCount * 8) + PACKET_SIZE_BITS) * encodingRatio);
|
|
if(packetReceivedBits.length > totalBits) {
|
|
// const excess = packetReceivedBits.length % totalBits;
|
|
// packetReceivedBits.length = totalBits;
|
|
// bitValues.length = bitValues.length - excess;
|
|
}
|
|
}
|
|
|
|
document.getElementById('decoded-data').innerHTML = packetDecodedBits.reduce(bitExpectorReducer(EXPECTED_BITS), '');
|
|
document.getElementById('received-data').innerHTML = packetReceivedBits.reduce(bitExpectorReducer(EXPECTED_ENCODED_BITS), '');
|
|
|
|
const encodedBitCount = EXPECTED_ENCODED_BITS.length;
|
|
const decodedBitCount = EXPECTED_BITS.length;
|
|
const correctEncodedBits = packetReceivedBits.filter((b, i) => i < encodedBitCount && b === EXPECTED_ENCODED_BITS[i]).length;
|
|
const correctedDecodedBits = packetDecodedBits.filter((b, i) => i < decodedBitCount && b === EXPECTED_BITS[i]).length;
|
|
document.getElementById('received-data-error-percent').innerText = (
|
|
Math.floor((1 - (correctEncodedBits / encodedBitCount)) * 1000) * 0.1
|
|
).toLocaleString();
|
|
document.getElementById('decoded-data-error-percent').innerText = (
|
|
Math.floor((1 - (correctedDecodedBits / decodedBitCount)) * 1000) * 0.1
|
|
).toLocaleString();
|
|
document.getElementById('decoded-text').innerHTML = packetDecodedBits.reduce(textExpectorReducer(EXPECTED_TEXT), '');
|
|
}
|
|
function bitReducer(all, bit, i) {
|
|
if(i !== 0 && i % 8 === 0) return all + ' ' + bit;
|
|
return all + bit;
|
|
}
|
|
const bitExpectorReducer = expected => (all, bit, i) => {
|
|
// if(i === 0) console.log(expected.slice(), all, bit, i);
|
|
|
|
if(i !== 0 && i % 8 === 0) all += ' ';
|
|
if(i >= expected.length) {
|
|
all += '<span class="bit-unexpected">';
|
|
} else if(expected[i] !== bit) {
|
|
all += '<span class="bit-wrong">';
|
|
}
|
|
all += bit.toString();
|
|
if(i >= expected.length || expected[i] !== bit) {
|
|
all += '</span>';
|
|
}
|
|
return all;
|
|
}
|
|
const textExpectorReducer = expected => (all, bit, i, bits) => {
|
|
if(i < PACKET_SIZE_BITS) return all;
|
|
if((i - PACKET_SIZE_BITS) % 8 === 0) {
|
|
const bitString = bits.slice(
|
|
i,
|
|
i + 8
|
|
).join('').padEnd(8, '0');
|
|
const ascii = parseInt(bitString, 2);
|
|
const char = String.fromCharCode(ascii);
|
|
const charIndex = Math.floor((i - PACKET_SIZE_BITS) / 8);
|
|
if(char !== expected[charIndex]) {
|
|
all += '<span class="bit-wrong">' + char + '</span>';
|
|
} else {
|
|
all += char;
|
|
}
|
|
}
|
|
return all;
|
|
}
|
|
|
|
function resetGraphData() {
|
|
frequencyOverTime.length = 0;
|
|
bitStart.length = 0;
|
|
}
|
|
function truncateGraphData() {
|
|
const duration = SEGMENT_DURATION * MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
const now = performance.now();
|
|
let length = frequencyOverTime.length;
|
|
while(length !== 0) {
|
|
const time = frequencyOverTime[length-1].time;
|
|
if(now - time > duration) length--;
|
|
else break;
|
|
}
|
|
if(length !== frequencyOverTime.length) {
|
|
frequencyOverTime.length = length;
|
|
bitStart.length = length;
|
|
}
|
|
}
|
|
function getAudioContext() {
|
|
if(!audioContext) {
|
|
audioContext = new (window.AudioContext || webkitAudioContext)();
|
|
}
|
|
if(audioContext.state === 'suspended') {
|
|
audioContext.resume();
|
|
}
|
|
return audioContext;
|
|
}
|
|
|
|
function textToBits(text) {
|
|
const bits = [];
|
|
for(let i = 0; i < text.length; i++) {
|
|
// const unicode = text.codePointAt(i).toString(2).padStart(16, '0');
|
|
const ascii = text[i].charCodeAt(0).toString(2).padStart(8, '0');
|
|
bits.push(ascii);
|
|
}
|
|
return bits.join('').split('').map(Number);
|
|
}
|
|
function handleSendButtonClick() {
|
|
receivedDataTextarea.value = '';
|
|
sentDataTextArea.value = '';
|
|
|
|
const text = document.getElementById('text-to-send').value;
|
|
EXPECTED_TEXT = text;
|
|
sendBits(textToBits(text));
|
|
}
|
|
function handleListeningCheckbox(e) {
|
|
stopGraph();
|
|
var audioContext = getAudioContext();
|
|
function handleMicrophoneOn(stream) {
|
|
microphoneStream = stream;
|
|
microphoneNode = audioContext.createMediaStreamSource(stream);
|
|
analyser = audioContext.createAnalyser();
|
|
analyser.smoothingTimeConstant = SMOOTHING_TIME_CONSTANT;
|
|
analyser.fftSize = 2 ** FFT_SIZE_POWER;
|
|
microphoneNode.connect(analyser);
|
|
resumeGraph();
|
|
}
|
|
function handleMicrophoneError(error) {
|
|
console.error('Microphone Error', error);
|
|
}
|
|
if(e.target.checked) {
|
|
navigator.mediaDevices
|
|
.getUserMedia({
|
|
audio: {
|
|
mandatory: {
|
|
autoGainControl: false,
|
|
echoCancellation: false,
|
|
noiseSuppression: false,
|
|
suppressLocalAudioPlayback: false,
|
|
voiceIsolation: false
|
|
},
|
|
optional: []
|
|
}
|
|
})
|
|
.then(handleMicrophoneOn)
|
|
.catch(handleMicrophoneError)
|
|
} else {
|
|
if(microphoneStream) {
|
|
microphoneStream.getTracks().forEach(track => track.stop());
|
|
microphoneStream = undefined;
|
|
}
|
|
if(analyser && microphoneNode) {
|
|
try {
|
|
analyser.disconnect(microphoneNode);
|
|
} catch(e) {
|
|
|
|
}
|
|
microphoneNode = undefined;
|
|
analyser = undefined;
|
|
}
|
|
}
|
|
}
|
|
function received(value) {
|
|
receivedDataTextarea.value += value;
|
|
receivedDataTextarea.scrollTop = receivedDataTextarea.scrollHeight;
|
|
}
|
|
let bitStarted;
|
|
let lastBitStarted;
|
|
let bitEnded;
|
|
let bitHighStrength = [];
|
|
let bitLowStrength = [];
|
|
let lastSegmentIndex = 0;
|
|
|
|
function canHear(hz, {frequencies, length}) {
|
|
var i = Math.round(hz / length);
|
|
return frequencies[i] > AMPLITUDE_THRESHOLD;
|
|
}
|
|
function amplitude(hz, {frequencies, length}) {
|
|
var i = Math.round(hz / length);
|
|
return frequencies[i];
|
|
}
|
|
const sum = (total, value) => total + value;
|
|
|
|
function avgLabel(array) {
|
|
const values = array.filter(v => v > 0);
|
|
if(values.length === 0) return 'N/A';
|
|
return (values.reduce((t, v) => t + v, 0) / values.length).toFixed(2)
|
|
}
|
|
function drawBitDurationLines(ctx, color) {
|
|
const { width, height } = receivedGraph;
|
|
const newest = frequencyOverTime[0].time;
|
|
const duration = SEGMENT_DURATION * MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
|
|
const streamTimes = frequencyOverTime.filter(({
|
|
streamStarted
|
|
}) => {
|
|
return streamStarted !== -1
|
|
}).reduce((unique, {
|
|
streamStarted,
|
|
streamEnded = newest
|
|
}) => {
|
|
if(unique.every(u => u.streamStarted != streamStarted)) {
|
|
unique.push({streamStarted, streamEnded})
|
|
}
|
|
return unique;
|
|
}, []);
|
|
|
|
ctx.strokeStyle = color;
|
|
streamTimes.forEach(({ streamStarted, streamEnded = newest}) => {
|
|
for(let time = streamStarted; time < streamEnded; time += SEGMENT_DURATION) {
|
|
if(newest - time > duration) continue;
|
|
const x = ((newest - time) / duration) * width;
|
|
ctx.beginPath();
|
|
ctx.moveTo(x, 0);
|
|
ctx.lineTo(x, height);
|
|
ctx.stroke();
|
|
}
|
|
// write end as well
|
|
const x = ((newest - streamEnded) / duration) * width;
|
|
ctx.beginPath();
|
|
ctx.moveTo(x, 0);
|
|
ctx.lineTo(x, height);
|
|
ctx.stroke();
|
|
});
|
|
}
|
|
|
|
function drawBitStart(ctx, color) {
|
|
const { width, height } = receivedGraph;
|
|
const newest = frequencyOverTime[0].time;
|
|
const duration = SEGMENT_DURATION * MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
ctx.strokeStyle = color;
|
|
for(let i = 0; i < bitStart.length; i++) {
|
|
if(!bitStart[i]) continue;
|
|
const {time} = frequencyOverTime[i];
|
|
if(newest - time > duration) continue;
|
|
const x = ((newest - time) / duration) * width;
|
|
ctx.beginPath();
|
|
ctx.moveTo(x, 0);
|
|
ctx.lineTo(x, height);
|
|
ctx.stroke();
|
|
}
|
|
}
|
|
function hzAmplitude(hz, length, frequencies) {
|
|
var index = Math.round(hz / length);
|
|
return frequencies[index];
|
|
}
|
|
function getPercentY(percent) {
|
|
const { height } = receivedGraph;
|
|
return (1 - percent) * height;
|
|
}
|
|
function drawFrequencyLineGraph(ctx, hz, color, lineWidth, dashed) {
|
|
const { width, height } = receivedGraph;
|
|
const newest = frequencyOverTime[0].time;
|
|
const duration = SEGMENT_DURATION * MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
ctx.strokeStyle = color;
|
|
ctx.lineWidth = lineWidth;
|
|
if(dashed) {
|
|
ctx.setLineDash([5, 5]);
|
|
}
|
|
ctx.beginPath();
|
|
for(let i = 0; i < frequencyOverTime.length; i++) {
|
|
const {frequencies, time, length} = frequencyOverTime[i];
|
|
const x = getTimeX(time, newest);
|
|
if(x === -1) continue;
|
|
const amplitude = hzAmplitude(hz, length, frequencies);
|
|
const y = getPercentY(amplitude / MAX_DATA);
|
|
if(i === 0) ctx.moveTo(x, y); else ctx.lineTo(x, y);
|
|
}
|
|
ctx.stroke();
|
|
if(dashed) {
|
|
ctx.setLineDash([]);
|
|
}
|
|
}
|
|
function drawFrequencyDots(ctx, hz, color) {
|
|
const newest = frequencyOverTime[0].time;
|
|
const radius = 2;
|
|
const border = 0.5;
|
|
ctx.fillStyle = color;
|
|
ctx.strokeStyle = 'white';
|
|
ctx.lineWidth = border;
|
|
const fullCircle = 2 * Math.PI;
|
|
for(let i = 0; i < frequencyOverTime.length; i++) {
|
|
const {frequencies, time, length} = frequencyOverTime[i];
|
|
const x = getTimeX(time, newest);
|
|
if(x === -1) continue;
|
|
const amplitude = hzAmplitude(hz, length, frequencies);
|
|
const y = getPercentY(amplitude / MAX_DATA);
|
|
|
|
ctx.beginPath();
|
|
ctx.arc(x, y, radius, 0, fullCircle);
|
|
ctx.fill();
|
|
|
|
ctx.beginPath();
|
|
ctx.arc(x, y, radius + border, 0, fullCircle);
|
|
ctx.stroke();
|
|
}
|
|
}
|
|
function getTimeX(time, newest) {
|
|
return getTimePercent(time, newest) * receivedGraph.width;
|
|
}
|
|
function getTimePercent(time, newest) {
|
|
const duration = SEGMENT_DURATION * MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
if(newest - time > duration) return -1;
|
|
return ((newest - time) / duration);
|
|
}
|
|
function drawChannelData() {
|
|
const canvas = document.getElementById('received-channel-graph');
|
|
const ctx = canvas.getContext('2d');
|
|
const {height, width} = canvas;
|
|
ctx.fillStyle = 'black';
|
|
ctx.fillRect(0, 0, width, height);
|
|
|
|
const sampleRate = getAudioContext().sampleRate;
|
|
const fftSize = 2 ** FFT_SIZE_POWER;
|
|
const frequencyResolution = sampleRate / fftSize;
|
|
//const frequencyCount = (sampleRate/2) / frequencyResolution;
|
|
const channels = getChannels();
|
|
const channelCount = channels.length;
|
|
const channelHeight = height / channelCount;
|
|
const bandHeight = channelHeight / 2;
|
|
|
|
const nyquistFrequency = audioContext.sampleRate / 2;
|
|
const frequencySegments = Math.floor(nyquistFrequency / frequencyResolution);
|
|
|
|
const newest = frequencyOverTime[0].time;
|
|
const duration = SEGMENT_DURATION * MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
const overlays = [];
|
|
|
|
for(let channelIndex = 0; channelIndex < channelCount; channelIndex++) {
|
|
const [low, high] = channels[channelIndex];
|
|
let top = channelHeight * channelIndex;
|
|
|
|
// ctx.fillStyle = channelIndex % 2 === 0 ? 'black' : 'white';
|
|
// ctx.fillRect(0, top, width, channelHeight);
|
|
|
|
// Data
|
|
// ctx.strokeStyle = 'blue';
|
|
|
|
const segmentDurationS = SEGMENT_DURATION;
|
|
|
|
// Segments
|
|
const segmentCount = Math.ceil(EXPECTED_ENCODED_BITS.length / channelCount);
|
|
const lastStream = frequencyOverTime.find(fot => fot.hasSignal);
|
|
const streamStarted = lastStream?.streamStarted ?? newest;
|
|
const lastSegmentIndex = lastStream?.segmentIndex ?? segmentCount;
|
|
const oldest = newest - (segmentDurationS * MAX_BITS_DISPLAYED_ON_GRAPH);
|
|
|
|
// Show segments with wrong bits
|
|
for(let segmentIndex = 0; segmentIndex <= lastSegmentIndex; segmentIndex++) {
|
|
const segmentBits = GET_SEGMENT_BITS(streamStarted, segmentIndex);
|
|
if(channelIndex >= segmentBits.length) continue; // past received/heard bits
|
|
const bitIndex = (segmentIndex * channelCount) + channelIndex;
|
|
if(bitIndex >= EXPECTED_ENCODED_BITS.length) continue; // past data stream
|
|
const segmentStart = streamStarted + (segmentIndex * segmentDurationS);
|
|
if(segmentStart > newest) break; // too far in the future
|
|
const segmentEnd = segmentStart + segmentDurationS;
|
|
if(segmentEnd < oldest) continue; // to far in the past
|
|
const endPercent = getTimePercent(segmentEnd, newest);
|
|
const startPercent = getTimePercent(segmentStart, newest);
|
|
const endX = (endPercent) * width;
|
|
const startX = (startPercent) * width;
|
|
const segmentWidth = startX - endX;
|
|
|
|
// evaluate received bit
|
|
const actualBit = segmentBits[channelIndex];
|
|
// identify expected bit
|
|
const expectedBit = EXPECTED_ENCODED_BITS[bitIndex];
|
|
|
|
// color red if received bit does not match expected bit
|
|
ctx.fillStyle = actualBit === expectedBit ? 'green' : 'red';
|
|
ctx.fillRect(endX, top, segmentWidth, channelHeight);
|
|
|
|
ctx.lineWidth = 0.5;
|
|
ctx.strokeStyle = 'rgba(255, 255, 255, 0.5)';
|
|
ctx.strokeRect(endX, top, segmentWidth, channelHeight);
|
|
|
|
// show bad value
|
|
// if(actualBit !== expectedBit) {
|
|
ctx.font = `${channelHeight}px Arial`;
|
|
const size = ctx.measureText(actualBit.toString());
|
|
const textHeight = size.actualBoundingBoxAscent + size.actualBoundingBoxDescent;
|
|
const centerChannel = top + (channelHeight / 2);
|
|
const textTop = centerChannel + (size.actualBoundingBoxAscent / 2);
|
|
|
|
overlays.push(() => {
|
|
ctx.strokeStyle = actualBit !== expectedBit ? 'black' : 'black';
|
|
ctx.lineWidth = 2;
|
|
ctx.strokeText(actualBit.toString(), endX + (segmentWidth/2) - (size.width / 2), textTop);
|
|
ctx.fillStyle = actualBit !== expectedBit ? 'white' : 'white';
|
|
ctx.fillText(actualBit.toString(), endX + (segmentWidth/2) - (size.width / 2), textTop);
|
|
})
|
|
|
|
// }
|
|
|
|
}
|
|
|
|
// for(let channelIndex = 0; channelIndex < channelCount; channelIndex++) {
|
|
// const [low, high] = channels[channelIndex];
|
|
// let top = channelHeight * channelIndex;
|
|
if(channelIndex % 8 === 0) {
|
|
ctx.strokeStyle = 'black';
|
|
ctx.lineWidth = 3;
|
|
ctx.beginPath();
|
|
ctx.moveTo(0, top-1);
|
|
ctx.lineTo(width, top-1);
|
|
ctx.stroke();
|
|
}
|
|
|
|
// channel number
|
|
ctx.font = `${channelHeight}px Arial`;
|
|
const size = ctx.measureText(channelIndex);
|
|
const textHeight = size.fontBoundingBoxAscent + size.fontBoundingBoxDescent;
|
|
const textTop = top + (channelHeight / 2) + (size.actualBoundingBoxAscent / 2);
|
|
// const textTop = top;//(top + (channelHeight / 2)) - (textHeight/2);
|
|
const hue = channelHue(channelIndex, channelCount);
|
|
ctx.fillStyle = `hsl(${hue}, 100%, 50%)`;
|
|
|
|
ctx.fillText(channelIndex, 5, textTop);
|
|
|
|
|
|
}
|
|
overlays.forEach(fn => fn());
|
|
|
|
}
|
|
function drawFrequencyData() {
|
|
if(PAUSE) return;
|
|
if(frequencyOverTime.length === 0) {
|
|
requestAnimationFrame(drawFrequencyData);
|
|
return;
|
|
}
|
|
drawChannelData();
|
|
const ctx = receivedGraph.getContext('2d');
|
|
const { width, height } = receivedGraph;
|
|
ctx.fillStyle = 'black';
|
|
ctx.fillRect(0, 0, width, height);
|
|
|
|
const thresholdY = (1 - (AMPLITUDE_THRESHOLD/MAX_DATA)) * height;
|
|
ctx.strokeStyle = 'grey';
|
|
ctx.beginPath();
|
|
ctx.moveTo(0, thresholdY);
|
|
ctx.lineTo(width, thresholdY);
|
|
ctx.stroke();
|
|
drawBitDurationLines(ctx, 'rgba(255, 255, 0, .25)');
|
|
drawBitStart(ctx, 'green');
|
|
const frequencies = getChannels();
|
|
frequencies.forEach(([low, high], i) => {
|
|
const hue = channelHue(i, frequencies.length);
|
|
drawFrequencyLineGraph(ctx, high, `hsl(${hue}, 100%, 50%)`, 2, false);
|
|
drawFrequencyLineGraph(ctx, low, `hsl(${hue}, 100%, 25%)`, 1, true);
|
|
});
|
|
|
|
requestAnimationFrame(drawFrequencyData);
|
|
}
|
|
|
|
function channelHue(channelId, channelCount) {
|
|
return Math.floor((channelId / channelCount) * 360);
|
|
}
|
|
|
|
function drawReceivedData() {
|
|
const ctx = receivedGraph.getContext('2d');
|
|
const { width, height } = receivedGraph;
|
|
const segmentWidth = (1 / MAX_BITS_DISPLAYED_ON_GRAPH) * width;
|
|
ctx.clearRect(0, 0, width, height);
|
|
const sorted = receivedData.slice().sort((a, b) => a - b);
|
|
const min = sorted[0];
|
|
const max = sorted[sorted.length - 1];
|
|
const range = max - min;
|
|
ctx.beginPath();
|
|
for(let i = 0; i < MAX_BITS_DISPLAYED_ON_GRAPH && i < receivedData.length; i++) {
|
|
const value = receivedData[i];
|
|
const y = (1-(value / range)) * height;
|
|
if(i === 0) {
|
|
ctx.moveTo(0, y);
|
|
} else {
|
|
ctx.lineTo(segmentWidth * i, y)
|
|
}
|
|
}
|
|
ctx.stroke();
|
|
}
|
|
|
|
|
|
window.addEventListener('load', handleWindowLoad); |