1640 lines
56 KiB
JavaScript
1640 lines
56 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_AMPLITUDE = 300; // Higher than 255 to give us space
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var pauseTimeoutId;
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var sampleIntervalIds = [];
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let EXCLUDED_CHANNELS = [];
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var TEXT_TO_SEND = "U";
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var RANDOM_COUNT = 128;
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var MAX_BITS_DISPLAYED_ON_GRAPH = 79;
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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 = 400;
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var MAXIMUM_FREQUENCY = 14650;
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var LAST_SEGMENT_PERCENT = 0.6;
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var FFT_SIZE_POWER = 9;
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var FREQUENCY_RESOLUTION_MULTIPLIER = 2;
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let CHANNEL_FREQUENCY_RESOLUTION_PADDING = 2;
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var SMOOTHING_TIME_CONSTANT = 0;
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var HAMMING_ERROR_CORRECTION = true;
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let PERIODIC_INTERLEAVING = true;
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let WAVE_FORM = "triangle";
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const ERROR_CORRECTION_BLOCK_SIZE = 7;
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let CHANNEL_OVER = -1;
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let CHANNEL_SELECTED = -1;
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let SEGMENT_OVER = -1;
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let SEGMENT_SELECTED = -1;
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var SEND_VIA_SPEAKER = false;
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var LAST_STREAM_STARTED;
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var MINIMUM_INTERVAL_MS = 3; // DO NOT SET THIS BELOW THE BROWSERS MINIMUM "real" INTERVAL
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const SAMPLING_INTERVAL_COUNT = 2;
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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 packetUninterlievedBits = [];
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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(RANDOM_COUNT).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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receivedChannelGraph = document.getElementById('received-channel-graph');
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receivedChannelGraph.addEventListener('mouseover', handleReceivedChannelGraphMouseover);
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receivedChannelGraph.addEventListener('mouseout', handleReceivedChannelGraphMouseout);
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receivedChannelGraph.addEventListener('mousemove', handleReceivedChannelGraphMousemove);
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receivedChannelGraph.addEventListener('click', handleReceivedChannelGraphClick);
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document.getElementById('wave-form').value = WAVE_FORM;
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document.getElementById('wave-form').addEventListener('change', (event) => {
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WAVE_FORM = event.target.value;
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})
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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('periodic-interleaving').checked = PERIODIC_INTERLEAVING;
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document.getElementById('periodic-interleaving').addEventListener('change', event => {
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PERIODIC_INTERLEAVING = event.target.checked;
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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('send-via-speaker').checked = SEND_VIA_SPEAKER;
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document.getElementById('send-via-speaker').addEventListener('input', event => {
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SEND_VIA_SPEAKER = event.target.checked;
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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('channel-frequency-resolution-padding').value = CHANNEL_FREQUENCY_RESOLUTION_PADDING;
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document.getElementById('channel-frequency-resolution-padding').addEventListener('input', event => {
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CHANNEL_FREQUENCY_RESOLUTION_PADDING = 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 allChannels = getChannels(true);
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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 / ERROR_CORRECTION_BLOCK_SIZE;
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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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allChannels.forEach(([low, high], i) => {
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const li = document.createElement('li');
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const label = document.createElement('label');
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li.appendChild(label);
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const checkbox = document.createElement('input');
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checkbox.type = 'checkbox';
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checkbox.checked = !EXCLUDED_CHANNELS.includes(i);
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checkbox.addEventListener('input', event => {
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if(event.target.checked) {
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EXCLUDED_CHANNELS = EXCLUDED_CHANNELS.filter(channel => channel !== i)
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} else {
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EXCLUDED_CHANNELS.push(i);
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}
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showSpeed();
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})
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label.append(checkbox);
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const text = document.createTextNode(`Low: ${low} Hz High: ${high} Hz`);
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label.append(text);
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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++) {
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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 !== ERROR_CORRECTION_BLOCK_SIZE) 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 removeInterleaving(bits) {
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return applyInterleaving(bits, true);
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}
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function applyInterleaving(bits, undo = false) {
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// Not turned on
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if(!PERIODIC_INTERLEAVING) return bits;
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// Only applicable for error correction
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if(!HAMMING_ERROR_CORRECTION) return bits;
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const channels = getChannels();
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const channelCount = channels.length;
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// We need at least 1 extra channel for one bit to escape the block
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if(channelCount < ERROR_CORRECTION_BLOCK_SIZE + 1) return bits;
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const blockCount = Math.ceil(channelCount / ERROR_CORRECTION_BLOCK_SIZE);
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// need another block to swap bits with
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if(blockCount < 2) return bits;
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// ensure last segment has enough bits to swap
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while(bits.length % channelCount !== 0) bits.push(0);
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// Loop through each segment
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for(let i = 0; i < bits.length; i+= channelCount) {
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// Grab the bits for the segment
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let segment = bits.slice(i, i + channelCount);
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segment = staggerValues(segment, ERROR_CORRECTION_BLOCK_SIZE, undo);
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// update the bits with the modified segment
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bits.splice(i, channelCount, ...segment);
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}
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return bits;
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}
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function staggerValues(values, blockSize, undo) {
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// loop through bit indexes of a block
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for(let blockMovement = 1; blockMovement < blockSize; blockMovement++) {
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values.filter((_, i) =>
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// values to be moved to different blocks
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i % blockSize === blockMovement
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).map((_,i,a) => {
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// bit values moved N blocks
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if(undo) i -= blockMovement; else i += blockMovement;
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i = ((i % a.length) + a.length) % a.length;
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return a[i];
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}).forEach((v, i) => {
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// replace with new values
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values[blockMovement + (i * blockSize)] = v;
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})
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};
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return values;
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}
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function applyErrorCorrection(bits) {
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if(!HAMMING_ERROR_CORRECTION) return bits;
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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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return encodedBits;
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}
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function getChannels(includeExcluded = false) {
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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 + CHANNEL_FREQUENCY_RESOLUTION_PADDING) * FREQUENCY_RESOLUTION_MULTIPLIER;
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let channelId = -1;
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for(let hz = MINIMUM_FREQUENCY; hz < MAXIMUM_FREQUENCY; hz+= pairStep) {
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const low = hz;
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const high = 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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channelId++;
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if(!includeExcluded) {
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if(EXCLUDED_CHANNELS.includes(channelId)) continue;
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}
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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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}
|
|
function sendBits(bits) {
|
|
const byteCount = bits.length / 8;
|
|
if(bits.length === 0) {
|
|
logSent('No bits to send!');
|
|
return;
|
|
} else if(bits.length % 8 !== 0 || bits.length === 0) {
|
|
logSent('Bit count must be divisible by 8.');
|
|
return;
|
|
} else if(byteCount > (1 << PACKET_SIZE_BITS)) {
|
|
logSent(`Can not transfer more than ${(1 << PACKET_SIZE_BITS)} bytes.`);
|
|
return;
|
|
}
|
|
|
|
const packetLength = ((byteCount - 1) >>> 0)
|
|
.toString(2)
|
|
.padStart(PACKET_SIZE_BITS, '0')
|
|
.split('')
|
|
.map(Number);
|
|
|
|
bits.unshift(...packetLength);
|
|
|
|
EXPECTED_BITS = bits.slice();
|
|
|
|
document.getElementById('sent-data').value = bits.reduce(bitReducer, '');
|
|
|
|
EXPECTED_ENCODED_BITS = bits = applyInterleaving(
|
|
applyErrorCorrection(bits)
|
|
);
|
|
document.getElementById('encoded-data').value = EXPECTED_ENCODED_BITS.reduce(bitReducer, '');
|
|
|
|
var audioContext = getAudioContext();
|
|
const channels = getChannels();
|
|
const oscillators = [];
|
|
const channelCount = channels.length;
|
|
|
|
const currentTime = audioContext.currentTime + 0.1;
|
|
|
|
const destination = SEND_VIA_SPEAKER ? audioContext.destination : getAnalyser();
|
|
|
|
// create our oscillators
|
|
for(let i = 0; i < channelCount; i++) {
|
|
var oscillator = audioContext.createOscillator();
|
|
|
|
oscillator.connect(destination);
|
|
oscillator.type = WAVE_FORM;
|
|
oscillators.push(oscillator);
|
|
}
|
|
|
|
// change our channel frequencies for the bit
|
|
for(let i = 0; i < bits.length; i++) {
|
|
const isHigh = bits[i];
|
|
const channel = i % channelCount;
|
|
const segment = Math.floor(i / channelCount);
|
|
var offset = ((segment * SEGMENT_DURATION)/1000);
|
|
var offset2 = (((segment+1) * SEGMENT_DURATION)/1000) - (1/100000);
|
|
oscillators[channel].frequency.setValueAtTime(
|
|
channels[channel][isHigh ? 1 : 0],
|
|
currentTime + offset
|
|
);
|
|
oscillators[channel].frequency.setValueAtTime(
|
|
channels[channel][isHigh ? 1 : 0],
|
|
currentTime + offset2
|
|
);
|
|
}
|
|
|
|
// start sending our signal
|
|
oscillators.forEach(o => o.start(currentTime));
|
|
|
|
// silence oscillators when done
|
|
for(let i = bits.length; i < bits.length + channelCount; i++) {
|
|
const channel = i % channelCount;
|
|
const segment = Math.floor(i / channelCount);
|
|
const offset = ((segment * SEGMENT_DURATION) / 1000);
|
|
oscillators[channel].frequency.setValueAtTime(0, currentTime + offset);
|
|
oscillators[channel].stop(currentTime + offset);
|
|
}
|
|
|
|
// start the graph moving again
|
|
resumeGraph();
|
|
}
|
|
function stopGraph() {
|
|
PAUSE = true;
|
|
stopCollectingSamples();
|
|
}
|
|
function startCollectingSamples() {
|
|
for(let i = 0; i < SAMPLING_INTERVAL_COUNT; i++) {
|
|
if(sampleIntervalIds[i]) continue;
|
|
sampleIntervalIds[i] = window.setInterval(
|
|
collectSample,
|
|
MINIMUM_INTERVAL_MS + (i/SAMPLING_INTERVAL_COUNT)
|
|
);
|
|
}
|
|
}
|
|
function stopCollectingSamples() {
|
|
sampleIntervalIds.forEach(window.clearInterval);
|
|
sampleIntervalIds = sampleIntervalIds.map(() => {});
|
|
}
|
|
function resumeGraph() {
|
|
if(isListeningCheckbox.checked) {
|
|
if(PAUSE) {
|
|
PAUSE = false;
|
|
startCollectingSamples();
|
|
resetGraphData();
|
|
requestAnimationFrame(drawFrequencyData);
|
|
} else {
|
|
PAUSE = false;
|
|
}
|
|
} else {
|
|
PAUSE = false;
|
|
}
|
|
}
|
|
function collectSample() {
|
|
const time = performance.now();
|
|
if(frequencyOverTime.length !== 0) {
|
|
// we already have this sample
|
|
if(time === frequencyOverTime[0].time) return;
|
|
}
|
|
const frequencies = new Uint8Array(analyser.frequencyBinCount);
|
|
analyser.getByteFrequencyData(frequencies);
|
|
const length = audioContext.sampleRate / analyser.fftSize;
|
|
let processSegment = false;
|
|
const {
|
|
hasSignal: hadPriorSignal,
|
|
streamStarted: initialStreamStart = -1,
|
|
streamEnded: priorStreamEnded = -1,
|
|
segmentIndex: priorSegmentIndex = -1
|
|
} = frequencyOverTime[0] ?? {}
|
|
const data = {
|
|
time,
|
|
// frequencies: [...frequencies],
|
|
length,
|
|
streamEnded: priorStreamEnded
|
|
};
|
|
// Get amplitude of each channels set of frequencies
|
|
data.pairs = getChannels().map(hzSet => hzSet.map(hz => frequencies[Math.round(hz / length)]));
|
|
const hasSignal = data.hasSignal = data.pairs.some(amps => amps.some(amp => amp > AMPLITUDE_THRESHOLD));
|
|
|
|
if(hasSignal) {
|
|
if(hadPriorSignal) {
|
|
// continued bit stream
|
|
data.streamStarted = initialStreamStart;
|
|
|
|
// proposed end
|
|
data.streamEnded = priorStreamEnded;
|
|
} else {
|
|
if(pauseTimeoutId) {
|
|
window.clearTimeout(pauseTimeoutId);
|
|
pauseTimeoutId = undefined;
|
|
// recover prior bit stream
|
|
data.streamStarted = LAST_STREAM_STARTED;
|
|
} else {
|
|
// new bit stream
|
|
data.streamStarted = time;
|
|
LAST_STREAM_STARTED = time;
|
|
// clear last packet
|
|
packetReceivedBits.length = 0;
|
|
packetUninterlievedBits.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 * 2);
|
|
}
|
|
} else {
|
|
// continued stopping (or never started)
|
|
data.streamEnded = -1;
|
|
}
|
|
}
|
|
frequencyOverTime.unshift(data);
|
|
if(processSegment) processSegmentReceived(initialStreamStart, priorSegmentIndex);
|
|
truncateGraphData();
|
|
}
|
|
|
|
function GET_SEGMENT_BITS(streamStarted, segmentIndex, originalOrder = false) {
|
|
const samples = frequencyOverTime.filter(f =>
|
|
f.segmentIndex === segmentIndex &&
|
|
f.streamStarted === streamStarted
|
|
);
|
|
const channelCount = frequencyOverTime[0].pairs.length;
|
|
const channelFrequencyCount = 2;
|
|
const sums = new Array(channelCount)
|
|
.fill(0)
|
|
.map(() =>
|
|
new Array(channelFrequencyCount)
|
|
.fill(0)
|
|
);
|
|
samples.forEach(({pairs}) => {
|
|
pairs.forEach((amps, channel) => {
|
|
amps.forEach((amp, i) => {
|
|
sums[channel][i] += amp;
|
|
});
|
|
});
|
|
});
|
|
const bitValues = sums.map((amps) => amps[0] > amps[1] ? 0 : 1);
|
|
return originalOrder ? bitValues : removeInterleaving(bitValues);
|
|
}
|
|
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
|
|
);
|
|
|
|
let bitValues;
|
|
if(samples.length === 0) {
|
|
// nothing collected
|
|
// bitValues = new Array(channelCount).fill(0);
|
|
return;
|
|
} else {
|
|
const sampleEnd = samples[0].time;
|
|
const sampleStart = streamStarted + (segmentIndex * SEGMENT_DURATION);
|
|
const sampleDuration = (sampleEnd - sampleStart) + MINIMUM_INTERVAL_MS;
|
|
|
|
// not long enough to qualify as a segment
|
|
if((sampleDuration / SEGMENT_DURATION) < LAST_SEGMENT_PERCENT) return;
|
|
|
|
bitValues = GET_SEGMENT_BITS(streamStarted, segmentIndex, true);
|
|
}
|
|
packetReceivedBits.push(...bitValues);
|
|
packetUninterlievedBits.push(...removeInterleaving(bitValues));
|
|
|
|
const encodingRatio = HAMMING_ERROR_CORRECTION ? ERROR_CORRECTION_BLOCK_SIZE/4 : 1;
|
|
if(HAMMING_ERROR_CORRECTION) {
|
|
packetDecodedBits.length = 0;
|
|
for(let i = 0; i < packetUninterlievedBits.length; i += ERROR_CORRECTION_BLOCK_SIZE) {
|
|
const hamming = packetUninterlievedBits.slice(i, i + ERROR_CORRECTION_BLOCK_SIZE);
|
|
const nibble = hammingToNibble(hamming);
|
|
packetDecodedBits.push(...nibble);
|
|
}
|
|
} else {
|
|
packetDecodedBits.length = 0;
|
|
packetDecodedBits.push(...packetUninterlievedBits);
|
|
}
|
|
|
|
// 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;
|
|
// 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 / packetReceivedBits.length)) * 1000) * 0.1
|
|
).toLocaleString();
|
|
document.getElementById('decoded-data-error-percent').innerText = (
|
|
Math.floor((1 - (correctedDecodedBits / packetDecodedBits.length)) * 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">' + htmlEncode(printable(char)) + '</span>';
|
|
} else {
|
|
all += htmlEncode(printable(char));
|
|
}
|
|
}
|
|
return all;
|
|
}
|
|
function printable(text) {
|
|
return text.replace(/[\x00-\x1f\x7f-\x9f]/g, '.');
|
|
}
|
|
function htmlEncode(text) {
|
|
const element = document.createElement('div');
|
|
element.textContent = text;
|
|
return element.innerHTML;
|
|
}
|
|
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 getAnalyser() {
|
|
if(analyser) return analyser;
|
|
analyser = audioContext.createAnalyser();
|
|
analyser.smoothingTimeConstant = SMOOTHING_TIME_CONSTANT;
|
|
analyser.fftSize = 2 ** FFT_SIZE_POWER;
|
|
return analyser;
|
|
}
|
|
function handleListeningCheckbox(e) {
|
|
stopGraph();
|
|
var audioContext = getAudioContext();
|
|
function handleMicrophoneOn(stream) {
|
|
microphoneStream = stream;
|
|
microphoneNode = audioContext.createMediaStreamSource(stream);
|
|
analyser = getAnalyser();
|
|
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 drawSegmentIndexes(ctx, width, height) {
|
|
// Do/did we have a stream?
|
|
if(!LAST_STREAM_STARTED) return;
|
|
const latest = frequencyOverTime[0].time;
|
|
|
|
// will any of the stream appear?
|
|
const packetDuration = getPacketDurationMilliseconds();
|
|
const lastStreamEnded = LAST_STREAM_STARTED + packetDuration;
|
|
const graphDuration = SEGMENT_DURATION * MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
const graphEarliest = latest - graphDuration;
|
|
// ended too long ago?
|
|
if(lastStreamEnded < graphEarliest) return;
|
|
|
|
const segmentWidth = width / MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
|
|
const latestSegmentEnded = Math.min(latest, lastStreamEnded);
|
|
|
|
for(let time = latestSegmentEnded; time > graphEarliest; time -= SEGMENT_DURATION) {
|
|
// too far back?
|
|
if(time < LAST_STREAM_STARTED) break;
|
|
|
|
// which segment are we looking at?
|
|
const segmentIndex = Math.floor(((time - LAST_STREAM_STARTED) / SEGMENT_DURATION));
|
|
|
|
// when did the segment begin/end
|
|
const segmentStart = LAST_STREAM_STARTED + (segmentIndex * SEGMENT_DURATION);
|
|
const segmentEnd = segmentStart + SEGMENT_DURATION;
|
|
|
|
// where is the segments left x coordinate?
|
|
const leftX = ((latest - segmentEnd) / graphDuration) * width;
|
|
|
|
// Draw segment index
|
|
ctx.fontSize = '24px';
|
|
if(segmentStart < lastStreamEnded) {
|
|
let text = segmentIndex.toString();
|
|
let size = ctx.measureText(text);
|
|
let textX = leftX + (segmentWidth / 2) - (size.width / 2);
|
|
ctx.strokeStyle = 'black';
|
|
ctx.lineWidth = 2;
|
|
ctx.textBaseline = 'bottom';
|
|
let textY = segmentIndex % 2 === 0 ? height : height - 12;
|
|
ctx.strokeText(text, textX, textY);
|
|
ctx.fillStyle = 'white';
|
|
ctx.fillText(text, textX, textY);
|
|
}
|
|
|
|
// draw sample count
|
|
const sampleCount = frequencyOverTime
|
|
.filter(fot =>
|
|
fot.streamStarted === LAST_STREAM_STARTED &&
|
|
fot.segmentIndex === segmentIndex
|
|
)
|
|
.length;
|
|
|
|
text = sampleCount.toString();
|
|
size = ctx.measureText(text);
|
|
textX = leftX + (segmentWidth / 2) - (size.width / 2);
|
|
textY = segmentIndex % 2 === 0 ? 5 : 17;
|
|
ctx.strokeStyle = 'black';
|
|
ctx.lineWidth = 2;
|
|
ctx.textBaseline = 'top';
|
|
ctx.strokeText(text, textX, textY);
|
|
if(sampleCount === 0) ctx.fillStyle = 'red';
|
|
else if(sampleCount < 3) ctx.fillStyle = 'yellow';
|
|
else ctx.fillStyle = 'white';
|
|
ctx.fillText(text, textX, textY);
|
|
}
|
|
}
|
|
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 getPercentY(percent) {
|
|
const { height } = receivedGraph;
|
|
return (1 - percent) * height;
|
|
}
|
|
function drawFrequencyLineGraph(ctx, channel, highLowIndex, color, lineWidth, dashed) {
|
|
const { width, height } = receivedGraph;
|
|
const newest = frequencyOverTime[0].time;
|
|
const duration = SEGMENT_DURATION * MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
const isSelected = channel === CHANNEL_SELECTED;
|
|
const isOver = channel === CHANNEL_OVER;
|
|
if(dashed) {
|
|
ctx.setLineDash([5, 5]);
|
|
}
|
|
ctx.beginPath();
|
|
for(let i = 0; i < frequencyOverTime.length; i++) {
|
|
const {pairs, time} = frequencyOverTime[i];
|
|
const x = getTimeX(time, newest);
|
|
if(x === -1) continue;
|
|
if(channel > pairs.length) continue;
|
|
const amplitude = pairs[channel][highLowIndex];
|
|
const y = getPercentY(amplitude / MAX_AMPLITUDE);
|
|
if(i === 0) ctx.moveTo(x, y); else ctx.lineTo(x, y);
|
|
}
|
|
if(isSelected || isOver) {
|
|
ctx.lineWidth = lineWidth + 5;
|
|
ctx.strokeStyle = 'white';
|
|
ctx.stroke();
|
|
}
|
|
ctx.strokeStyle = color;
|
|
ctx.lineWidth = lineWidth;
|
|
ctx.stroke();
|
|
if(dashed) {
|
|
ctx.setLineDash([]);
|
|
}
|
|
}
|
|
function drawFrequencyDots(ctx, channel, highLowIndex, 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 {pairs, time} = frequencyOverTime[i];
|
|
const x = getTimeX(time, newest);
|
|
if(x === -1) continue;
|
|
const amplitude = pairs[channel][highLowIndex];
|
|
const y = getPercentY(amplitude / MAX_AMPLITUDE);
|
|
|
|
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 getDataBitCount() {
|
|
const text = document.getElementById('text-to-send').value;
|
|
const dataByteCount = text.length;
|
|
return dataByteCount * 8;
|
|
}
|
|
function getPacketSizeUnencodedBitCount() {
|
|
return getDataBitCount() + PACKET_SIZE_BITS;
|
|
}
|
|
function getErrorCorrectionBlocks() {
|
|
if(!HAMMING_ERROR_CORRECTION) return 0;
|
|
const dataBitCount = getPacketSizeUnencodedBitCount();
|
|
return Math.ceil(dataBitCount / 4);
|
|
}
|
|
function getErrorCorrectionBitCount() {
|
|
return getErrorCorrectionBlocks() * 3;
|
|
}
|
|
function getPacketSizeEncodedBitCount() {
|
|
return getErrorCorrectionBitCount() + getPacketSizeUnencodedBitCount();
|
|
}
|
|
function getPacketSizeEncodedByteCount() {
|
|
return Math.ceil(getPacketSizeEncodedBitCount() / 8);
|
|
}
|
|
function getPacketSizeSegmentCount() {
|
|
const totalBits = getPacketSizeEncodedBitCount();
|
|
const channelCount = getChannels().length;
|
|
return Math.ceil(totalBits / channelCount);
|
|
}
|
|
function getPacketDurationMilliseconds() {
|
|
const segmentCount = getPacketSizeSegmentCount();
|
|
return segmentCount * SEGMENT_DURATION;
|
|
}
|
|
function drawChannelData() {
|
|
// Do/did we have a stream?
|
|
if(!LAST_STREAM_STARTED) return;
|
|
|
|
const latest = frequencyOverTime[0].time;
|
|
|
|
// will any of the stream appear?
|
|
const packetBitCount = getPacketSizeEncodedBitCount();
|
|
|
|
const packetDuration = getPacketDurationMilliseconds();
|
|
const lastStreamEnded = LAST_STREAM_STARTED + packetDuration;
|
|
const graphDuration = SEGMENT_DURATION * MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
const graphEarliest = latest - graphDuration;
|
|
// ended too long ago?
|
|
if(lastStreamEnded < graphEarliest) return;
|
|
|
|
const channels = getChannels();
|
|
const channelCount = channels.length;
|
|
|
|
const canvas = document.getElementById('received-channel-graph');
|
|
|
|
clearCanvas(canvas);
|
|
const ctx = canvas.getContext('2d');
|
|
const {height, width} = canvas;
|
|
|
|
// Loop through visible segments
|
|
const latestSegmentEnded = Math.min(latest, lastStreamEnded);//yyy
|
|
for(let time = latestSegmentEnded; time > graphEarliest; time -= SEGMENT_DURATION) {
|
|
// too far back?
|
|
if(time < LAST_STREAM_STARTED) break;
|
|
|
|
// which segment are we looking at?
|
|
const segmentIndex = Math.floor(((time - LAST_STREAM_STARTED) / SEGMENT_DURATION));
|
|
|
|
// when did the segment begin/end
|
|
const segmentStart = LAST_STREAM_STARTED + (segmentIndex * SEGMENT_DURATION);
|
|
const segmentEnd = segmentStart + SEGMENT_DURATION;
|
|
|
|
// where is the segments left x coordinate?
|
|
const leftX = ((latest - segmentEnd) / graphDuration) * width;
|
|
|
|
// what bits did we receive for the segment?
|
|
const segmentBits = GET_SEGMENT_BITS(LAST_STREAM_STARTED, segmentIndex, true);
|
|
|
|
// draw segment data background
|
|
let expectedBitCount = channelCount;
|
|
if(segmentEnd === lastStreamEnded) {
|
|
expectedBitCount = packetBitCount % channelCount;
|
|
} else if(segmentEnd > lastStreamEnded) {
|
|
continue;
|
|
}
|
|
drawSegmentBackground(
|
|
ctx,
|
|
segmentIndex,
|
|
leftX,
|
|
expectedBitCount,
|
|
channelCount,
|
|
width,
|
|
height
|
|
)
|
|
|
|
for(let channelIndex = 0; channelIndex < channelCount; channelIndex++) {
|
|
// get received bit
|
|
const receivedBit = segmentBits[channelIndex];
|
|
// identify expected bit
|
|
const bitIndex = channelIndex + (segmentIndex * channelCount);
|
|
if(bitIndex >= EXPECTED_ENCODED_BITS.length) break;
|
|
const expectedBit = EXPECTED_ENCODED_BITS[bitIndex];
|
|
|
|
drawChannelSegmentBackground(
|
|
ctx,
|
|
leftX,
|
|
segmentIndex,
|
|
channelIndex,
|
|
channelCount,
|
|
height,
|
|
width,
|
|
receivedBit,
|
|
expectedBit
|
|
);
|
|
|
|
drawChannelSegmentForeground(
|
|
ctx,
|
|
leftX,
|
|
channelIndex,
|
|
channelCount,
|
|
height,
|
|
width,
|
|
receivedBit,
|
|
expectedBit
|
|
);
|
|
}
|
|
}
|
|
drawChannelByteMarkers(ctx, channelCount, width, height);
|
|
drawSelectedChannel(ctx, channelCount, width, height);
|
|
drawChannelNumbers(ctx, channelCount, width, height)
|
|
}
|
|
function clearCanvas(canvas) {
|
|
const ctx = canvas.getContext('2d');
|
|
const {height, width} = canvas;
|
|
ctx.fillStyle = 'black';
|
|
ctx.fillRect(0, 0, width, height);
|
|
}
|
|
function drawSegmentBackground(
|
|
ctx,
|
|
segmentIndex,
|
|
leftX,
|
|
expectedBitCount,
|
|
channelCount,
|
|
width,
|
|
height
|
|
) {
|
|
const segmentWidth = width / MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
|
|
const hue = 120;
|
|
let luminance = segmentIndex % 2 === 0 ? 30 : 25;
|
|
if(SEGMENT_SELECTED === segmentIndex || SEGMENT_OVER === segmentIndex) luminance += 15;
|
|
|
|
ctx.fillStyle = `hsl(${hue}, 100%, ${luminance}%)`;
|
|
const segmentHeight = (expectedBitCount / channelCount) * height
|
|
ctx.fillRect(leftX, 0, segmentWidth, segmentHeight);
|
|
}
|
|
function drawChannelSegmentForeground(
|
|
ctx,
|
|
endX,
|
|
channelIndex,
|
|
channelCount,
|
|
height,
|
|
width,
|
|
actualBit,
|
|
expectedBit
|
|
) {
|
|
const channelHeight = height / channelCount;
|
|
const segmentWidth = width / MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
let fontHeight = Math.min(24, channelHeight, segmentWidth);
|
|
let top = channelHeight * channelIndex;
|
|
ctx.font = `${fontHeight}px Arial`;
|
|
const size = ctx.measureText(actualBit.toString());
|
|
ctx.textBaseline = 'middle';
|
|
const textTop = top + (channelHeight / 2);
|
|
if(actualBit === expectedBit) {
|
|
ctx.strokeStyle = actualBit !== expectedBit ? 'black' : 'black';
|
|
ctx.lineWidth = 2;
|
|
ctx.strokeText(actualBit.toString(), endX + (segmentWidth/2) - (size.width / 2), textTop);
|
|
}
|
|
ctx.fillStyle = actualBit !== expectedBit ? '#2d0c0c' : 'white';
|
|
ctx.fillText(actualBit.toString(), endX + (segmentWidth/2) - (size.width / 2), textTop);
|
|
|
|
}
|
|
function drawChannelSegmentBackground(
|
|
ctx,
|
|
endX,
|
|
segmentIndex,
|
|
channelIndex,
|
|
channelCount,
|
|
height,
|
|
width,
|
|
actualBit,
|
|
expectedBit
|
|
) {
|
|
const isSelectedOrOver =
|
|
(CHANNEL_OVER === channelIndex && SEGMENT_OVER === segmentIndex) ||
|
|
(CHANNEL_SELECTED === channelIndex && SEGMENT_SELECTED === segmentIndex);
|
|
|
|
const isCorrect = expectedBit === actualBit;
|
|
if(isCorrect && !isSelectedOrOver) return;
|
|
|
|
// color red if received bit does not match expected bit
|
|
const hue = isCorrect ? 120 : 0;
|
|
let luminance = isCorrect ? 50 : 80;
|
|
if(isSelectedOrOver) luminance += 15;
|
|
|
|
const channelHeight = height / channelCount;
|
|
const segmentWidth = width / MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
let top = channelHeight * channelIndex;
|
|
ctx.fillStyle = `hsl(${hue}, 100%, ${luminance}%)`;
|
|
ctx.fillRect(endX, top, segmentWidth, channelHeight);
|
|
|
|
ctx.lineWidth = 0.5;
|
|
ctx.strokeStyle = 'rgba(255, 255, 255, 0.5)';
|
|
ctx.strokeRect(endX, top, segmentWidth, channelHeight);
|
|
}
|
|
function drawChannelByteMarkers(ctx, channelCount, width, height) {
|
|
const channelHeight = height / channelCount;
|
|
for(let channelIndex = 8; channelIndex < channelCount; channelIndex+= 8) {
|
|
let top = channelHeight * channelIndex;
|
|
ctx.strokeStyle = 'black';
|
|
ctx.lineWidth = 3;
|
|
ctx.beginPath();
|
|
ctx.moveTo(0, top);
|
|
ctx.lineTo(width, top);
|
|
ctx.stroke();
|
|
}
|
|
}
|
|
function drawSelectedChannel(ctx, channelCount, width, height) {
|
|
const channelHeight = height / channelCount;
|
|
ctx.globalCompositionOperation = 'overlay';
|
|
ctx.fillStyle = 'hsla(0, 0%, 100%, 0.25)';
|
|
if(CHANNEL_OVER !== -1) {
|
|
ctx.fillRect(0, CHANNEL_OVER * channelHeight, width, channelHeight);
|
|
}
|
|
if(CHANNEL_SELECTED !== -1 && CHANNEL_SELECTED !== CHANNEL_OVER) {
|
|
ctx.fillRect(0, CHANNEL_SELECTED * channelHeight, width, channelHeight);
|
|
}
|
|
ctx.globalCompositionOperation = 'source-over';
|
|
}
|
|
function drawChannelNumbers(ctx, channelCount, width, height) {
|
|
const offset = 0;
|
|
const channelHeight = height / channelCount;
|
|
const segmentWidth = width / MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
let fontHeight = Math.min(24, channelHeight, segmentWidth);
|
|
ctx.font = `${fontHeight}px Arial`;
|
|
ctx.textBaseline = 'middle';
|
|
ctx.fillStyle = 'rgba(0, 0, 0, .5)';
|
|
const maxDigits = (channelCount - 1).toString().length;
|
|
ctx.fillRect(offset, 0, (fontHeight * maxDigits), channelHeight * channelCount);
|
|
for(let channelIndex = 0; channelIndex < channelCount; channelIndex++) {
|
|
let top = channelHeight * channelIndex;
|
|
let text = realChannel(channelIndex).toString();
|
|
const textTop = top + (channelHeight / 2);
|
|
const hue = channelHue(channelIndex, channelCount);
|
|
ctx.fillStyle = `hsl(${hue}, 100%, 50%)`;
|
|
ctx.fillText(text, offset + 5, textTop);
|
|
}
|
|
}
|
|
function realChannel(id) {
|
|
EXCLUDED_CHANNELS.sort(compareNumbers);
|
|
for(let i = 0; i < EXCLUDED_CHANNELS.length; i++) {
|
|
if(EXCLUDED_CHANNELS[i] <= id) id++;
|
|
}
|
|
return id;
|
|
}
|
|
function drawFrequencyData(forcedDraw) {
|
|
if(PAUSE && forcedDraw !== true) return;
|
|
if(frequencyOverTime.length === 0) {
|
|
if(forcedDraw !== true) {
|
|
requestAnimationFrame(drawFrequencyData);
|
|
}
|
|
return;
|
|
}
|
|
drawChannelData();
|
|
const ctx = receivedGraph.getContext('2d');
|
|
const { width, height } = receivedGraph;
|
|
ctx.fillStyle = 'black';
|
|
ctx.fillRect(0, 0, width, height);
|
|
|
|
const thresholdY = (1 - (AMPLITUDE_THRESHOLD/MAX_AMPLITUDE)) * height;
|
|
ctx.strokeStyle = 'grey';
|
|
ctx.beginPath();
|
|
ctx.moveTo(0, thresholdY);
|
|
ctx.lineTo(width, thresholdY);
|
|
ctx.stroke();
|
|
drawBitDurationLines(ctx, 'rgba(255, 255, 0, .25)');
|
|
drawBitStart(ctx, 'green');
|
|
const frequencies = getChannels();
|
|
const high = 1;
|
|
const low = 0
|
|
const isSelectedOrOver = CHANNEL_OVER !== -1 || CHANNEL_SELECTED !== -1;
|
|
const highLuminance = isSelectedOrOver ? 25 : 50;
|
|
const lowLuminance = isSelectedOrOver ? 12 : 25;
|
|
frequencies.forEach((v, channel) => {
|
|
const hue = channelHue(channel, frequencies.length);
|
|
drawFrequencyLineGraph(ctx, channel, high, `hsl(${hue}, 100%, ${highLuminance}%)`, 2, false);
|
|
drawFrequencyLineGraph(ctx, channel, low, `hsl(${hue}, 100%, ${lowLuminance}%)`, 1, true);
|
|
});
|
|
if(CHANNEL_OVER !== -1) {
|
|
const hue = channelHue(CHANNEL_OVER, frequencies.length);
|
|
drawFrequencyLineGraph(ctx, CHANNEL_OVER, high, `hsl(${hue}, 100%, 50%)`, 2, false);
|
|
drawFrequencyLineGraph(ctx, CHANNEL_OVER, low, `hsl(${hue}, 100%, 25%)`, 1, true);
|
|
} else if(CHANNEL_SELECTED !== -1) {
|
|
const hue = channelHue(CHANNEL_SELECTED, frequencies.length);
|
|
drawFrequencyLineGraph(ctx, CHANNEL_SELECTED, high, `hsl(${hue}, 100%, 50%)`, 2, false);
|
|
drawFrequencyLineGraph(ctx, CHANNEL_SELECTED, low, `hsl(${hue}, 100%, 25%)`, 1, true);
|
|
}
|
|
|
|
drawSegmentIndexes(ctx, width, height);
|
|
|
|
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();
|
|
}
|
|
|
|
function handleReceivedChannelGraphMouseover(e) {
|
|
const {channelIndex, segmentIndex} = getChannelAndSegment(e);
|
|
CHANNEL_OVER = channelIndex;
|
|
SEGMENT_OVER = segmentIndex;
|
|
requestAnimationFrame(drawFrequencyData.bind(null, true));
|
|
}
|
|
function handleReceivedChannelGraphMouseout(e) {
|
|
CHANNEL_OVER = -1;
|
|
SEGMENT_OVER = -1;
|
|
requestAnimationFrame(drawFrequencyData.bind(null, true));
|
|
}
|
|
function handleReceivedChannelGraphMousemove(e) {
|
|
const {channelIndex, segmentIndex} = getChannelAndSegment(e);
|
|
CHANNEL_OVER = channelIndex;
|
|
SEGMENT_OVER = segmentIndex;
|
|
requestAnimationFrame(drawFrequencyData.bind(null, true));
|
|
}
|
|
function mouseXy({clientX, clientY, target}) {
|
|
const rect = target.getBoundingClientRect();
|
|
return {
|
|
x: clientX - rect.left,
|
|
y: clientY - rect.top
|
|
}
|
|
}
|
|
function handleReceivedChannelGraphClick(e) {
|
|
const {channelIndex, segmentIndex} = getChannelAndSegment(e);
|
|
CHANNEL_SELECTED = channelIndex;
|
|
SEGMENT_SELECTED = segmentIndex;
|
|
const channels = getChannels();
|
|
const channelCount = channels.length;
|
|
|
|
const selectedSamples = document.getElementById('selected-samples');
|
|
selectedSamples.innerHTML = "";
|
|
|
|
function addLowHigh(info, low, high) {
|
|
const div = document.createElement('div');
|
|
div.className = 'low-high-set'
|
|
const infoDiv = document.createElement('div');
|
|
infoDiv.className = 'ingo';
|
|
const lowDiv = document.createElement('div');
|
|
lowDiv.className = 'low';
|
|
const highDiv = document.createElement('div');
|
|
highDiv.className = 'high';
|
|
infoDiv.innerText = info;
|
|
lowDiv.innerText = low;
|
|
highDiv.innerText = high;
|
|
if(low === 255) lowDiv.classList.add('max');
|
|
if(high === 255) highDiv.classList.add('max');
|
|
if(typeof low === 'number' && typeof high === 'number') {
|
|
if(low > high) lowDiv.classList.add('highest');
|
|
else highDiv.classList.add('highest');
|
|
}
|
|
div.appendChild(infoDiv);
|
|
div.appendChild(lowDiv);
|
|
div.appendChild(highDiv);
|
|
selectedSamples.appendChild(div);
|
|
}
|
|
|
|
if(CHANNEL_SELECTED !== -1) {
|
|
addLowHigh('', 'Low', 'High');
|
|
addLowHigh('Hz',
|
|
channels[CHANNEL_SELECTED][0].toLocaleString(),
|
|
channels[CHANNEL_SELECTED][1].toLocaleString()
|
|
)
|
|
}
|
|
if(SEGMENT_SELECTED === -1) {
|
|
document.getElementById('selected-segment').innerText = 'N/A';
|
|
} else {
|
|
document.getElementById('selected-segment').innerText = SEGMENT_SELECTED;
|
|
if(CHANNEL_SELECTED !== -1) {
|
|
|
|
const bitIndex = CHANNEL_SELECTED + (SEGMENT_SELECTED * channelCount);
|
|
document.getElementById('selected-bit').innerText = bitIndex.toLocaleString();
|
|
|
|
const samples = frequencyOverTime
|
|
.filter(fot => fot.segmentIndex === SEGMENT_SELECTED)
|
|
.map(fot => fot.pairs[CHANNEL_SELECTED]);
|
|
samples.forEach(([low, high], i) => {
|
|
if(i === 0) {
|
|
addLowHigh(`Amplitude ${i}`, low, high);
|
|
} else {
|
|
[priorLow, priorHigh] = samples[i - 1];
|
|
addLowHigh(`Amplitude ${i}`,
|
|
priorLow === low ? '"' : low,
|
|
priorHigh === high ? '"' : high
|
|
);
|
|
|
|
}
|
|
});
|
|
|
|
const expectedBit = EXPECTED_ENCODED_BITS[bitIndex];
|
|
const receivedBit = packetReceivedBits[bitIndex];
|
|
addLowHigh('Expected Bit', expectedBit === 1 ? '' : '0', expectedBit === 1 ? '1' : '')
|
|
addLowHigh('Received Bit', receivedBit === 1 ? '' : '0', receivedBit === 1 ? '1' : '')
|
|
|
|
const sums = samples.reduce((sum, [low, high]) => {
|
|
sum[0]+= low;
|
|
sum[1]+= high;
|
|
return sum;
|
|
}, [0, 0]);
|
|
addLowHigh('Total', sums[0], sums[1]);
|
|
|
|
const sorts = samples.reduce((sum, [low, high]) => {
|
|
sum.low.push(low);
|
|
sum.high.push(high)
|
|
return sum;
|
|
}, {low: [], high: []});
|
|
sorts.low.sort(compareNumbers);
|
|
sorts.high.sort(compareNumbers);
|
|
const middleIndex = Math.floor(samples.length / 2);
|
|
|
|
addLowHigh('Median', sorts.low[middleIndex], sorts.high[middleIndex]);
|
|
|
|
}
|
|
}
|
|
|
|
if(CHANNEL_SELECTED === -1) {
|
|
document.getElementById('selected-channel').innerText = 'N/A';
|
|
} else {
|
|
document.getElementById('selected-channel').innerText = realChannel(CHANNEL_SELECTED);
|
|
}
|
|
|
|
|
|
requestAnimationFrame(drawFrequencyData.bind(null, true));
|
|
}
|
|
function compareNumbers(a, b) {
|
|
return a - b;
|
|
}
|
|
function getChannelAndSegment(e) {
|
|
const {width, height} = e.target.getBoundingClientRect();
|
|
const {x,y} = mouseXy(e);
|
|
if(y < 0 || x < 0 || y > height || x > width) return {
|
|
channelIndex: -1,
|
|
segmentIndex: -1
|
|
};
|
|
// what channel are we over?
|
|
const channels = getChannels();
|
|
const channelCount = channels.length;
|
|
let channelIndex = Math.floor((y / height) * channelCount);
|
|
if(channelIndex === channelCount) channelIndex--;
|
|
|
|
// what segment are we over?
|
|
// Do/did we have a stream?
|
|
if(!LAST_STREAM_STARTED) {
|
|
return {
|
|
channelIndex,
|
|
segmentIndex: -1
|
|
};
|
|
}
|
|
const latest = frequencyOverTime[0].time;
|
|
// will any of the stream appear?
|
|
const packetDuration = getPacketDurationMilliseconds();
|
|
const lastStreamEnded = LAST_STREAM_STARTED + packetDuration;
|
|
const graphDuration = SEGMENT_DURATION * MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
const graphEarliest = latest - graphDuration;
|
|
// ended too long ago?
|
|
if(lastStreamEnded < graphEarliest) {
|
|
return {
|
|
channelIndex,
|
|
segmentIndex: -1
|
|
};
|
|
}
|
|
|
|
const segmentWidth = width / MAX_BITS_DISPLAYED_ON_GRAPH;
|
|
|
|
const latestSegmentEnded = Math.min(latest, lastStreamEnded);
|
|
|
|
for(let time = latestSegmentEnded; time > graphEarliest; time -= SEGMENT_DURATION) {
|
|
// too far back?
|
|
if(time < LAST_STREAM_STARTED) {
|
|
return {
|
|
channelIndex,
|
|
segmentIndex: -1
|
|
}
|
|
};
|
|
|
|
// which segment are we looking at?
|
|
const segmentIndex = Math.floor(((time - LAST_STREAM_STARTED) / SEGMENT_DURATION));
|
|
|
|
// when did the segment begin/end
|
|
const segmentStart = LAST_STREAM_STARTED + (segmentIndex * SEGMENT_DURATION);
|
|
const segmentEnd = segmentStart + SEGMENT_DURATION;
|
|
|
|
// where is the segments left x coordinate?
|
|
const leftX = ((latest - segmentEnd) / graphDuration) * width;
|
|
// where is the segments right x coordinate?
|
|
const rightX = leftX + segmentWidth;
|
|
|
|
if(x >= leftX && x <= rightX) {
|
|
return {
|
|
channelIndex,
|
|
segmentIndex
|
|
}
|
|
}
|
|
}
|
|
|
|
return {
|
|
channelIndex,
|
|
segmentIndex: -1
|
|
}
|
|
|
|
}
|
|
window.addEventListener('load', handleWindowLoad); |