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| 1 | +<!DOCTYPE html> |
| 2 | +<html lang="en"> |
| 3 | +<head> |
| 4 | + <meta charset="UTF-8" /> |
| 5 | + <meta name="viewport" content="width=device-width, initial-scale=1.0"/> |
| 6 | + <title>Camera + Visual Search</title> |
| 7 | + <script src="https://cdn.jsdelivr.net/npm/@tensorflow/tfjs@4.11.0/dist/tf.min.js"></script> |
| 8 | + <script src="https://cdn.jsdelivr.net/npm/@tensorflow-models/mobilenet@3.1.0/dist/mobilenet.min.js"></script> |
| 9 | + <style> |
| 10 | + body { font-family: Arial, sans-serif; text-align: center; padding: 1em; } |
| 11 | + video, canvas { width: 100%; max-width: 400px; } |
| 12 | + #result-img { margin-top: 1em; max-width: 400px; } |
| 13 | + </style> |
| 14 | +</head> |
| 15 | +<body> |
| 16 | + |
| 17 | + <h1>Visual Search from Camera</h1> |
| 18 | + |
| 19 | + <video id="video" autoplay playsinline></video> |
| 20 | + <br /> |
| 21 | + <button id="capture-btn">Take Photo</button> |
| 22 | + |
| 23 | + <canvas id="capture-canvas" style="display:none;"></canvas> |
| 24 | + |
| 25 | + <h2>Most Similar Match:</h2> |
| 26 | + <img id="result-img" alt="Matching image will appear here"> |
| 27 | + |
| 28 | + <script> |
| 29 | + let model; |
| 30 | + const video = document.getElementById("video"); |
| 31 | + const canvas = document.getElementById("capture-canvas"); |
| 32 | + const ctx = canvas.getContext("2d"); |
| 33 | + const resultImg = document.getElementById("result-img"); |
| 34 | + |
| 35 | + // 1️⃣ Start camera |
| 36 | + async function startCamera() { |
| 37 | + const stream = await navigator.mediaDevices.getUserMedia({ video: true }); |
| 38 | + video.srcObject = stream; |
| 39 | + } |
| 40 | + |
| 41 | + // 2️⃣ Load MobileNet |
| 42 | + async function loadModel() { |
| 43 | + model = await mobilenet.load(); |
| 44 | + console.log("MobileNet loaded"); |
| 45 | + } |
| 46 | + |
| 47 | + // 3️⃣ Fetch JSON collection |
| 48 | + async function loadCollection() { |
| 49 | + const res = await fetch( |
| 50 | + "https://johnstack.github.io/JavaScript-Sandpit/ng_sandbox/collection.sample.json" |
| 51 | + ); |
| 52 | + const json = await res.json(); |
| 53 | + return json.items; // adjust based on JSON structure |
| 54 | + } |
| 55 | + |
| 56 | + // 4️⃣ Compute embedding |
| 57 | + async function getEmbedding(imgElement) { |
| 58 | + const logits = model.infer(imgElement, "conv_preds"); |
| 59 | + return logits.dataSync(); // embedding vector |
| 60 | + } |
| 61 | + |
| 62 | + // 5️⃣ Compute cosine similarity |
| 63 | + function cosineSim(a, b) { |
| 64 | + let dot = 0, magA = 0, magB = 0; |
| 65 | + for (let i = 0; i < a.length; i++) { |
| 66 | + dot += a[i] * b[i]; |
| 67 | + magA += a[i] * a[i]; |
| 68 | + magB += b[i] * b[i]; |
| 69 | + } |
| 70 | + return dot / (Math.sqrt(magA) * Math.sqrt(magB)); |
| 71 | + } |
| 72 | + |
| 73 | + // 6️⃣ Find nearest |
| 74 | + async function findNearest(captureImg, collection) { |
| 75 | + const captureEmbedding = await getEmbedding(captureImg); |
| 76 | + |
| 77 | + let bestSim = -1; |
| 78 | + let bestImg = null; |
| 79 | + |
| 80 | + for (let item of collection) { |
| 81 | + // load collection image |
| 82 | + const tempImg = new Image(); |
| 83 | + tempImg.crossOrigin = "anonymous"; |
| 84 | + tempImg.src = item.url; // adjust if JSON key differs |
| 85 | + |
| 86 | + await new Promise((resolve) => { |
| 87 | + tempImg.onload = resolve; |
| 88 | + tempImg.onerror = resolve; // skip broken links |
| 89 | + }); |
| 90 | + |
| 91 | + const emb = await getEmbedding(tempImg); |
| 92 | + const sim = cosineSim(captureEmbedding, emb); |
| 93 | + |
| 94 | + if (sim > bestSim) { |
| 95 | + bestSim = sim; |
| 96 | + bestImg = item.url; |
| 97 | + } |
| 98 | + } |
| 99 | + return bestImg; |
| 100 | + } |
| 101 | + |
| 102 | + |
| 103 | + // 🔘 Capture button logic |
| 104 | + document.getElementById("capture-btn").addEventListener("click", async () => { |
| 105 | + canvas.width = video.videoWidth; |
| 106 | + canvas.height = video.videoHeight; |
| 107 | + ctx.drawImage(video, 0, 0); |
| 108 | + |
| 109 | + const dataUrl = canvas.toDataURL("image/jpeg"); |
| 110 | + const captureImg = new Image(); |
| 111 | + captureImg.src = dataUrl; |
| 112 | + |
| 113 | + captureImg.onload = async () => { |
| 114 | + resultImg.src = "Searching..."; |
| 115 | + const collection = await loadCollection(); |
| 116 | + const nearestUrl = await findNearest(captureImg, collection); |
| 117 | + |
| 118 | + if (nearestUrl) { |
| 119 | + resultImg.src = nearestUrl; |
| 120 | + } else { |
| 121 | + resultImg.alt = "No similar image found"; |
| 122 | + } |
| 123 | + }; |
| 124 | + }); |
| 125 | + |
| 126 | + |
| 127 | + // Initialize |
| 128 | + startCamera(); |
| 129 | + loadModel(); |
| 130 | + </script> |
| 131 | + |
| 132 | +</body> |
| 133 | +</html> |
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