JS调用安卓手机摄像头扫描二维码
网络 2018-11-13 1405
项目要求：
使用H5模仿微信扫一扫付款功能
经过一系列的查找最后发现可以使用 JS调用手机摄像头然后用画布把当前摄像头的数据转成Base64的png图片，经过QrCode直接再本地识别。
优点：
兼容大多数浏览器
本地识别不占用服务端资源
代码比较简单只有一个页面
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 | <html lang="ZH-CN"> <head> <meta charset="utf-8"> <title>Web QrCode Test</title> <script type="text/javascript" src="jquery-1.8.3.min.js"></script> <script type="text/javascript" src="jsqrcode/src/grid.js"></script> <script type="text/javascript" src="jsqrcode/src/version.js"></script> <script type="text/javascript" src="jsqrcode/src/detector.js"></script> <script type="text/javascript" src="jsqrcode/src/formatinf.js"></script> <script type="text/javascript" src="jsqrcode/src/errorlevel.js"></script> <script type="text/javascript" src="jsqrcode/src/bitmat.js"></script> <script type="text/javascript" src="jsqrcode/src/datablock.js"></script> <script type="text/javascript" src="jsqrcode/src/bmparser.js"></script> <script type="text/javascript" src="jsqrcode/src/datamask.js"></script> <script type="text/javascript" src="jsqrcode/src/rsdecoder.js"></script> <script type="text/javascript" src="jsqrcode/src/gf256poly.js"></script> <script type="text/javascript" src="jsqrcode/src/gf256.js"></script> <script type="text/javascript" src="jsqrcode/src/decoder.js"></script> <script type="text/javascript" src="jsqrcode/src/qrcode.js"></script> <script type="text/javascript" src="jsqrcode/src/findpat.js"></script> <script type="text/javascript" src="jsqrcode/src/alignpat.js"></script> <script type="text/javascript" src="jsqrcode/src/databr.js"></script> </head> <body> <div class="booth"> <video id="video" width="400" height="400"></video> <canvas id='canvas' width='400' height='400'></canvas> <img id='img' src=''> </div> <div id="mmm"></div> <canvas id="qr-canvas" width="640" height="480"></canvas> <script> //初始化媒体对象 var c=0; var video = document.getElementById('video'), canvas = document.getElementById('canvas'), img = document.getElementById('img'), vendorUrl = window.URL || window.webkitURL; //媒体对象 navigator.getMedia = navigator.getUserMedia || navagator.webkitGetUserMedia || navigator.mozGetUserMedia || navigator.msGetUserMedia; navigator.getMedia({ video: true, //使用摄像头对象 audio: false //不适用音频 }, function(strem){ console.log(strem); video.src = vendorUrl.createObjectURL(strem); video.play(); }, function(error) { //error.code console.log(error); }); //启动定时器 setTimeout("actionP(null)","1000"); //定时器 function actionP(data){ if(data==null){ Screenshot() }else{ if(data!=null & data!="error decoding QR Code"){//识别出数据 if(data.indexOf("http")!=-1){ window.location.href=data; }else alert(data); }else{//没有数据循环十次 c++; if(c<10){ setTimeout("actionP(null)","1000"); } } } } function Screenshot(){//截取图像 canvas.getContext('2d').drawImage(video, 0, 0, 400, 400); var imgData = canvas.toDataURL("image/png"); load(imgData); img.src=imgData; } ////////////////////////////////////////识别二维码//////////////////////////////////////////// function dragenter(e) { e.stopPropagation(); e.preventDefault(); } function dragover(e) { e.stopPropagation(); e.preventDefault(); } function drop(e) { e.stopPropagation(); e.preventDefault(); var dt = e.dataTransfer; var files = dt.files; } function load(name) { initCanvas(640,480); //识别二维码并回调方法 qrcode.callback = actionP; qrcode.decode(name); } function initCanvas(ww,hh)//创建画板 { gCanvas = document.getElementById("qr-canvas"); gCanvas.addEventListener("dragenter", dragenter, false); gCanvas.addEventListener("dragover", dragover, false); gCanvas.addEventListener("drop", drop, false); var w = ww; var h = hh; gCanvas.style.width = w + "px"; gCanvas.style.height = h + "px"; gCanvas.width = w; gCanvas.height = h; gCtx = gCanvas.getContext("2d"); gCtx.clearRect(0, 0, w, h); imageData = gCtx.getImageData( 0,0,320,240); } </script> </body> </html> |
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