演示地址: HTML5拍照演示
首先,我們看看HTML代碼結(jié)構(gòu),當(dāng)然,這部分的DOM內(nèi)容應(yīng)該是在用戶允許使用其攝像頭事件出發(fā)后,動(dòng)態(tài)加載生成的。
注意: 我們采用的是 640X480的分辨率,如果采用JS動(dòng)態(tài)生成,那么您是可以靈活控制分辨率的。
<!--
聲明: 此div應(yīng)該在允許使用webcam,網(wǎng)絡(luò)攝像頭之后動(dòng)態(tài)生成
寬高: 640 *480,當(dāng)然,可以動(dòng)態(tài)控制啦!
-->
<!--
Ideally these elements aren't created until it's confirmed that the
client supports video/camera, but for the sake of illustrating the
elements involved, they are created with markup (not JavaScript)
-->
<video id="video" width="640" height="480" autoplay></video>
<button id="snap">Snap Photo</button>
<canvas id="canvas" width="640" height="480"></canvas>
JavaScript
只要上面的HTML元素創(chuàng)建完成,那么JavaScript部分將簡(jiǎn)單的超乎你想象的簡(jiǎn)單:
// 設(shè)置事件監(jiān)聽,DOM內(nèi)容加載完成,和jQuery的$.ready() 效果差不多。
window.addEventListener("DOMContentLoaded", function() {
// canvas 元素將用于抓拍
var canvas = document.getElementById("canvas"),
context = canvas.getContext("2d"),
// video 元素,將用于接收并播放攝像頭 的數(shù)據(jù)流
video = document.getElementById("video"),
videoObj = { "video": true },
// 一個(gè)出錯(cuò)的回調(diào)函數(shù),在控制臺(tái)打印出錯(cuò)信息
errBack = function(error) {
if("object" === typeof window.console){
console.log("Video capture error: ", error.code);
}
};
// Put video listeners into place
// 針對(duì)標(biāo)準(zhǔn)的瀏覽器
if(navigator.getUserMedia) { // Standard
navigator.getUserMedia(videoObj, function(stream) {
video.src = stream;
video.play();
}, errBack);
} else if(navigator.webkitGetUserMedia) { // WebKit-prefixed
navigator.webkitGetUserMedia(videoObj, function(stream){
video.src = window.webkitURL.createObjectURL(stream);
video.play();
}, errBack);
}
// 對(duì)拍照按鈕的事件監(jiān)聽
document.getElementById("snap").addEventListener("click", function() {
// 畫到畫布上
context.drawImage(video, 0, 0, 640, 480);
});
}, false);
最后,記得講您的網(wǎng)頁(yè)放到web服務(wù)器下面,然后通過(guò)http協(xié)議來(lái)訪問(wèn)哦。
另外,需要瀏覽器版本較新,并且支持HTML5的相關(guān)新特性才可以。
譯者不算稱職啦,沒(méi)有按原文來(lái)翻譯。使用的瀏覽器是chrome 28。
最后,貼上完整的代碼,比較呆板。
<!DOCTYPE html>
<html>
<head>
<title> 瀏覽器webcamera </title>
<meta name="Generator" content="EditPlus">
<meta name="Author" content="renfufei@qq.com">
<meta name="Description" content="inveted by: http://davidwalsh.name/browser-camera">
<script>
// 設(shè)置事件監(jiān)聽,DOM內(nèi)容加載完成,和jQuery的$.ready() 效果差不多。
window.addEventListener("DOMContentLoaded", function() {
// canvas 元素將用于抓拍
var canvas = document.getElementById("canvas"),
context = canvas.getContext("2d"),
// video 元素,將用于接收并播放攝像頭 的數(shù)據(jù)流
video = document.getElementById("video"),
videoObj = { "video": true },
// 一個(gè)出錯(cuò)的回調(diào)函數(shù),在控制臺(tái)打印出錯(cuò)信息
errBack = function(error) {
if("object" === typeof window.console){
console.log("Video capture error: ", error.code);
}
};
// Put video listeners into place
// 針對(duì)標(biāo)準(zhǔn)的瀏覽器
if(navigator.getUserMedia) { // Standard
navigator.getUserMedia(videoObj, function(stream) {
video.src = stream;
video.play();
}, errBack);
} else if(navigator.webkitGetUserMedia) { // WebKit-prefixed
navigator.webkitGetUserMedia(videoObj, function(stream){
video.src = window.webkitURL.createObjectURL(stream);
video.play();
}, errBack);
}
// 對(duì)拍照按鈕的事件監(jiān)聽
document.getElementById("snap").addEventListener("click", function() {
// 畫到畫布上
context.drawImage(video, 0, 0, 640, 480);
});
}, false);
</script>
</head>
<body>
<div>
<!--
聲明: 此div應(yīng)該在允許使用webcam,網(wǎng)絡(luò)攝像頭之后動(dòng)態(tài)生成
寬高: 640 *480,當(dāng)然,可以動(dòng)態(tài)控制啦!
-->
<!--
Ideally these elements aren't created until it's confirmed that the
client supports video/camera, but for the sake of illustrating the
elements involved, they are created with markup (not JavaScript)
-->
<video id="video" width="640" height="480" autoplay></video>
<button id="snap">Snap Photo</button>
<canvas id="canvas" width="640" height="480"></canvas>
</div>
</body>
</html>