HTML5 實現掃描識別二維碼 生成二維碼
阿新 • • 發佈：2019-01-31
掃描識別二維碼
思路 1. 操作攝像頭，獲取圖片。HTML5 WEBRTC的navigator.getUserMedia方法去實時獲取攝像頭資源。 2. 利用canvas使用相關演算法分析圖片識別圖片得出結果，可用jquery.qrcode分析二維碼 。（技術點：getImageData）侷限性 移動平臺支援getUserMedia/Stream API的瀏覽器比較少，支援列表http://caniuse.com/#feat=stream （目前沒發現有IOS是支援的） IOS替代方案筆記： 呼叫攝像頭拍照，把圖片傳到h5頁面。然後在解析。| 12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061 | <!DOCTYPE HTML><html><head><title>上傳圖片</title><meta charset="utf-8"></head><body><iframe name="uploadfrm" id="uploadfrm" style="display: none;"></iframe><form name="formHead" method="post" action="" id="formHead" enctype="multipart/form-data"target="uploadfrm"><div><div><input type="file" name="file_head" id="file_head" onchange="javascript:setImagePreview();" /></div><div><div id="DivUp" style="display: none"><input type="submit" data-inline="true" id="BtnUp" value="確認上傳" data-mini="true" /></div></div></div></form><div data-role="fieldcontain"><div id="localImag"><img id="preview" width="-1" height="-1" style="display: none" /></div></div><script type="text/javascript">function setImagePreview() {var preview, img_txt, localImag, file_head = document.getElementById("file_head"),picture = file_head.value;if (!picture.match(/.jpg|.gif|.png|.bmp/i)) return alert("您上傳的圖片格式不正確，請重新選擇！"),!1;if (preview = document.getElementById("preview"), file_head.files && file_head.files[0]) preview.style.display = "block",preview.style.width = "63px",preview.style.height = "63px",preview.src = window.navigator.userAgent.indexOf("Chrome") >= 1 || window.navigator.userAgent.indexOf("Safari") >= 1 ? window.webkitURL.createObjectURL(file_head.files[0]) : window.URL.createObjectURL(file_head.files[0]);else {file_head.select(),file_head.blur(),img_txt = document.selection.createRange().text,localImag = document.getElementById("localImag"),localImag.style.width = "63px",localImag.style.height = "63px";try {localImag.style.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=scale)",localImag.filters.item("DXImageTransform.Microsoft.AlphaImageLoader").src = img_txt} catch(f) {return alert("您上傳的圖片格式不正確，請重新選擇！"),!1}preview.style.display = "none",document.selection.empty()}return document.getElementById("DivUp").style.display = "block",!0}</script></body></html> |
程式碼實現 感謝github，有現成的演算法 具體實現程式碼：