AngularJS中使用HTML5手机摄像头拍照

AngularJS中使用HTML5手机摄像头拍照的完整攻略如下:

AngularJS中使用HTML5手机摄像头拍照的完整攻略如下:

HTML5摄像头API简介

HTML5提供了访问设备摄像头的API,这个API是Navigator.getUserMedia(),它用于打开摄像头,并且访问摄像头捕获的视频流。

实现步骤

  1. 获取用户摄像头的许可
  2. 创建一个video元素
  3. 将摄像头捕获的视频流绑定到video元素上
  4. 创建一个Canvas元素
  5. 将video元素的视频绘制在Canvas上
  6. 从Canvas上获取图像
  7. 将图像编码成data URI格式的字符串
  8. 将data URI存储在AngularJS变量中

示例一:使用HTML5实现拍照功能

<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>拍照</title>
    <script src="https://cdn.bootcdn.net/ajax/libs/angular.js/1.8.2/angular.min.js"></script>
    <style type="text/css">
        video{
            width: 100%;
            max-width: 300px;
            height: auto;
        }
        canvas{
            display: none;
        }
        img{
            max-width: 300px;
            height: auto;
        }
    </style>
</head>
<body ng-app="myApp" ng-controller="myCtrl">
    <button ng-click="start()">开始拍照</button>
    <video id="video" autoplay></video>
    <canvas id="canvas"></canvas>
    <img ng-src="{{imgSrc}}">
    <script type="text/javascript">
        var app = angular.module('myApp', []);
        app.controller('myCtrl', function($scope) {
            var video = document.querySelector("#video");
            var canvas = document.querySelector("#canvas");
            navigator.mediaDevices.getUserMedia({ video: true, audio: false })
                .then(function(stream) {
                    video.srcObject = stream;
                })
                .catch(function(err) {
                    console.log("error", err);
                });
            $scope.start = function(){
                canvas.width = video.videoWidth;
                canvas.height = video.videoHeight;
                canvas.getContext('2d').drawImage(video, 0, 0, canvas.width, canvas.height);
                $scope.imgSrc = canvas.toDataURL();
            }
        });
    </script>
</body>
</html>

示例二:将拍照结果上传至服务器

<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>拍照上传</title>
    <script src="https://cdn.bootcdn.net/ajax/libs/angular.js/1.8.2/angular.min.js"></script>
    <style type="text/css">
        video{
            width: 100%;
            max-width: 300px;
            height: auto;
        }
        canvas{
            display: none;
        }
        img{
            max-width: 300px;
            height: auto;
        }
    </style>
</head>
<body ng-app="myApp" ng-controller="myCtrl">
    <button ng-click="start()">开始拍照</button>
    <video id="video" autoplay></video>
    <canvas id="canvas"></canvas>
    <img ng-src="{{imgSrc}}">
    <button ng-click="upload()">上传</button>
    <script type="text/javascript">
        var app = angular.module('myApp', []);
        app.controller('myCtrl', function($scope, $http) {
            var video = document.querySelector("#video");
            var canvas = document.querySelector("#canvas");
            navigator.mediaDevices.getUserMedia({ video: true, audio: false })
                .then(function(stream) {
                    video.srcObject = stream;
                })
                .catch(function(err) {
                    console.log("error", err);
                });
            $scope.start = function(){
                canvas.width = video.videoWidth;
                canvas.height = video.videoHeight;
                canvas.getContext('2d').drawImage(video, 0, 0, canvas.width, canvas.height);
                $scope.imgSrc = canvas.toDataURL();
            }
            $scope.upload = function(){
                var dataUrl = $scope.imgSrc.replace(/^data:image\/(png|jpg);base64,/, "");
                $http.post('/api/uploadImage', dataUrl)
                    .then(function(response) {
                        console.log("success", response);
                    }, function(response) {
                        console.log("error", response);
                    });
            }
        });
    </script>
</body>
</html>

以上就是使用HTML5摄像头API实现拍照功能的攻略。

本文标题为:AngularJS中使用HTML5手机摄像头拍照

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