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// WebcamJS v1.0.6
// Webcam library for capturing JPEG/PNG images in JavaScript
// Attempts getUserMedia, falls back to Flash
// Author: Joseph Huckaby: http://github.com/jhuckaby
// Based on JPEGCam: http://code.google.com/p/jpegcam/
// Copyright (c) 2012 - 2015 Joseph Huckaby
// Licensed under the MIT License
(function(window) {
var Webcam = { version: '1.0.6', // globals
protocol: location.protocol.match(/https/i) ? 'https' : 'http', swfURL: '', // URI to webcam.swf movie (defaults to the js location)
loaded: false, // true when webcam movie finishes loading
live: false, // true when webcam is initialized and ready to snap
userMedia: true, // true when getUserMedia is supported natively
params: { width: 0, height: 0, dest_width: 0, // size of captured image
dest_height: 0, // these default to width/height
image_format: 'jpeg', // image format (may be jpeg or png)
jpeg_quality: 90, // jpeg image quality from 0 (worst) to 100 (best)
force_flash: false, // force flash mode,
flip_horiz: false, // flip image horiz (mirror mode)
fps: 30, // camera frames per second
upload_name: 'webcam', // name of file in upload post data
constraints: null // custom user media constraints
}, hooks: {}, // callback hook functions
init: function() { // initialize, check for getUserMedia support
var self = this; // Setup getUserMedia, with polyfill for older browsers
// Adapted from: https://developer.mozilla.org/en-US/docs/Web/API/MediaDevices/getUserMedia
this.mediaDevices = (navigator.mediaDevices && navigator.mediaDevices.getUserMedia) ? navigator.mediaDevices : ((navigator.mozGetUserMedia || navigator.webkitGetUserMedia) ? { getUserMedia: function(c) { return new Promise(function(y, n) { (navigator.mozGetUserMedia || navigator.webkitGetUserMedia).call(navigator, c, y, n); }); } } : null); window.URL = window.URL || window.webkitURL || window.mozURL || window.msURL; this.userMedia = this.userMedia && !!this.mediaDevices && !!window.URL; // Older versions of firefox (< 21) apparently claim support but user media does not actually work
if (navigator.userAgent.match(/Firefox\D+(\d+)/)) { if (parseInt(RegExp.$1, 10) < 21) this.userMedia = null; } // Make sure media stream is closed when navigating away from page
if (this.userMedia) { window.addEventListener( 'beforeunload', function(event) { self.reset(); } ); } }, attach: function(elem) { // create webcam preview and attach to DOM element
// pass in actual DOM reference, ID, or CSS selector
if (typeof(elem) == 'string') { elem = document.getElementById(elem) || document.querySelector(elem); } if (!elem) { return this.dispatch('error', "Could not locate DOM element to attach to."); } this.container = elem; elem.innerHTML = ''; // start with empty element
// insert "peg" so we can insert our preview canvas adjacent to it later on
var peg = document.createElement('div'); elem.appendChild( peg ); this.peg = peg; // set width/height if not already set
if (!this.params.width) this.params.width = elem.offsetWidth; if (!this.params.height) this.params.height = elem.offsetHeight; // set defaults for dest_width / dest_height if not set
if (!this.params.dest_width) this.params.dest_width = this.params.width; if (!this.params.dest_height) this.params.dest_height = this.params.height; // if force_flash is set, disable userMedia
if (this.params.force_flash) this.userMedia = null; // check for default fps
if (typeof this.params.fps !== "number") this.params.fps = 30;
// adjust scale if dest_width or dest_height is different
var scaleX = this.params.width / this.params.dest_width; var scaleY = this.params.height / this.params.dest_height; if (this.userMedia) { // setup webcam video container
var video = document.createElement('video'); video.setAttribute('autoplay', 'autoplay'); video.style.width = '' + this.params.dest_width + 'px'; video.style.height = '' + this.params.dest_height + 'px'; if ((scaleX != 1.0) || (scaleY != 1.0)) { elem.style.overflow = 'hidden'; video.style.webkitTransformOrigin = '0px 0px'; video.style.mozTransformOrigin = '0px 0px'; video.style.msTransformOrigin = '0px 0px'; video.style.oTransformOrigin = '0px 0px'; video.style.transformOrigin = '0px 0px'; video.style.webkitTransform = 'scaleX('+scaleX+') scaleY('+scaleY+')'; video.style.mozTransform = 'scaleX('+scaleX+') scaleY('+scaleY+')'; video.style.msTransform = 'scaleX('+scaleX+') scaleY('+scaleY+')'; video.style.oTransform = 'scaleX('+scaleX+') scaleY('+scaleY+')'; video.style.transform = 'scaleX('+scaleX+') scaleY('+scaleY+')'; } // add video element to dom
elem.appendChild( video ); this.video = video; // ask user for access to their camera
var self = this; this.mediaDevices.getUserMedia({ "audio": false, "video": this.params.constraints || { mandatory: { minWidth: this.params.dest_width, minHeight: this.params.dest_height } } }) .then( function(stream) { // got access, attach stream to video
video.src = window.URL.createObjectURL( stream ) || stream; self.stream = stream; self.loaded = true; self.live = true; self.dispatch('load'); self.dispatch('live'); self.flip(); }) .catch( function(err) { return self.dispatch('error', "Could not access webcam: " + err.name + ": " + err.message, err); }); } else { // flash fallback
window.Webcam = Webcam; // needed for flash-to-js interface
var div = document.createElement('div'); div.innerHTML = this.getSWFHTML(); elem.appendChild( div ); } // setup final crop for live preview
if (this.params.crop_width && this.params.crop_height) { var scaled_crop_width = Math.floor( this.params.crop_width * scaleX ); var scaled_crop_height = Math.floor( this.params.crop_height * scaleY ); elem.style.width = '' + scaled_crop_width + 'px'; elem.style.height = '' + scaled_crop_height + 'px'; elem.style.overflow = 'hidden'; elem.scrollLeft = Math.floor( (this.params.width / 2) - (scaled_crop_width / 2) ); elem.scrollTop = Math.floor( (this.params.height / 2) - (scaled_crop_height / 2) ); } else { // no crop, set size to desired
elem.style.width = '' + this.params.width + 'px'; elem.style.height = '' + this.params.height + 'px'; } }, reset: function() { // shutdown camera, reset to potentially attach again
if (this.preview_active) this.unfreeze(); // attempt to fix issue #64
this.unflip(); if (this.userMedia) { if (this.stream) { if (this.stream.getVideoTracks) { // get video track to call stop on it
var tracks = this.stream.getVideoTracks(); if (tracks && tracks[0] && tracks[0].stop) tracks[0].stop(); } else if (this.stream.stop) { // deprecated, may be removed in future
this.stream.stop(); } } delete this.stream; delete this.video; } if (this.container) { this.container.innerHTML = ''; delete this.container; } this.loaded = false; this.live = false; }, set: function() { // set one or more params
// variable argument list: 1 param = hash, 2 params = key, value
if (arguments.length == 1) { for (var key in arguments[0]) { this.params[key] = arguments[0][key]; } } else { this.params[ arguments[0] ] = arguments[1]; } }, on: function(name, callback) { // set callback hook
name = name.replace(/^on/i, '').toLowerCase(); if (!this.hooks[name]) this.hooks[name] = []; this.hooks[name].push( callback ); }, off: function(name, callback) { // remove callback hook
name = name.replace(/^on/i, '').toLowerCase(); if (this.hooks[name]) { if (callback) { // remove one selected callback from list
var idx = this.hooks[name].indexOf(callback); if (idx > -1) this.hooks[name].splice(idx, 1); } else { // no callback specified, so clear all
this.hooks[name] = []; } } }, dispatch: function() { // fire hook callback, passing optional value to it
var name = arguments[0].replace(/^on/i, '').toLowerCase(); var args = Array.prototype.slice.call(arguments, 1); if (this.hooks[name] && this.hooks[name].length) { for (var idx = 0, len = this.hooks[name].length; idx < len; idx++) { var hook = this.hooks[name][idx]; if (typeof(hook) == 'function') { // callback is function reference, call directly
hook.apply(this, args); } else if ((typeof(hook) == 'object') && (hook.length == 2)) { // callback is PHP-style object instance method
hook[0][hook[1]].apply(hook[0], args); } else if (window[hook]) { // callback is global function name
window[ hook ].apply(window, args); } } // loop
return true; } else if (name == 'error') { // default error handler if no custom one specified
alert("Webcam.js Error: " + args[0]); } return false; // no hook defined
}, setSWFLocation: function(url) { // set location of SWF movie (defaults to webcam.swf in cwd)
this.swfURL = url; }, detectFlash: function() { // return true if browser supports flash, false otherwise
// Code snippet borrowed from: https://github.com/swfobject/swfobject
var SHOCKWAVE_FLASH = "Shockwave Flash", SHOCKWAVE_FLASH_AX = "ShockwaveFlash.ShockwaveFlash", FLASH_MIME_TYPE = "application/x-shockwave-flash", win = window, nav = navigator, hasFlash = false; if (typeof nav.plugins !== "undefined" && typeof nav.plugins[SHOCKWAVE_FLASH] === "object") { var desc = nav.plugins[SHOCKWAVE_FLASH].description; if (desc && (typeof nav.mimeTypes !== "undefined" && nav.mimeTypes[FLASH_MIME_TYPE] && nav.mimeTypes[FLASH_MIME_TYPE].enabledPlugin)) { hasFlash = true; } } else if (typeof win.ActiveXObject !== "undefined") { try { var ax = new ActiveXObject(SHOCKWAVE_FLASH_AX); if (ax) { var ver = ax.GetVariable("$version"); if (ver) hasFlash = true; } } catch (e) {;} } return hasFlash; }, getSWFHTML: function() { // Return HTML for embedding flash based webcam capture movie
var html = ''; // make sure we aren't running locally (flash doesn't work)
if (location.protocol.match(/file/)) { this.dispatch('error', "Flash does not work from local disk. Please run from a web server."); return '<h3 style="color:red">ERROR: the Webcam.js Flash fallback does not work from local disk. Please run it from a web server.</h3>'; } // make sure we have flash
if (!this.detectFlash()) { this.dispatch('error', "Adobe Flash Player not found. Please install from get.adobe.com/flashplayer and try again."); return '<h3 style="color:red">ERROR: No Adobe Flash Player detected. Webcam.js relies on Flash for browsers that do not support getUserMedia (like yours).</h3>'; } // set default swfURL if not explicitly set
if (!this.swfURL) { // find our script tag, and use that base URL
var base_url = ''; var scpts = document.getElementsByTagName('script'); for (var idx = 0, len = scpts.length; idx < len; idx++) { var src = scpts[idx].getAttribute('src'); if (src && src.match(/\/webcam(\.min)?\.js/)) { base_url = src.replace(/\/webcam(\.min)?\.js.*$/, ''); idx = len; } } if (base_url) this.swfURL = base_url + '/webcam.swf'; else this.swfURL = 'webcam.swf'; } // if this is the user's first visit, set flashvar so flash privacy settings panel is shown first
if (window.localStorage && !localStorage.getItem('visited')) { this.params.new_user = 1; localStorage.setItem('visited', 1); } // construct flashvars string
var flashvars = ''; for (var key in this.params) { if (flashvars) flashvars += '&'; flashvars += key + '=' + escape(this.params[key]); } // construct object/embed tag
html += '<object classid="clsid:d27cdb6e-ae6d-11cf-96b8-444553540000" type="application/x-shockwave-flash" codebase="'+this.protocol+'://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=9,0,0,0" width="'+this.params.width+'" height="'+this.params.height+'" id="webcam_movie_obj" align="middle"><param name="wmode" value="opaque" /><param name="allowScriptAccess" value="always" /><param name="allowFullScreen" value="false" /><param name="movie" value="'+this.swfURL+'" /><param name="loop" value="false" /><param name="menu" value="false" /><param name="quality" value="best" /><param name="bgcolor" value="#ffffff" /><param name="flashvars" value="'+flashvars+'"/><embed id="webcam_movie_embed" src="'+this.swfURL+'" wmode="opaque" loop="false" menu="false" quality="best" bgcolor="#ffffff" width="'+this.params.width+'" height="'+this.params.height+'" name="webcam_movie_embed" align="middle" allowScriptAccess="always" allowFullScreen="false" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer" flashvars="'+flashvars+'"></embed></object>'; return html; }, getMovie: function() { // get reference to movie object/embed in DOM
if (!this.loaded) return this.dispatch('error', "Flash Movie is not loaded yet"); var movie = document.getElementById('webcam_movie_obj'); if (!movie || !movie._snap) movie = document.getElementById('webcam_movie_embed'); if (!movie) this.dispatch('error', "Cannot locate Flash movie in DOM"); return movie; }, freeze: function() { // show preview, freeze camera
var self = this; var params = this.params; // kill preview if already active
if (this.preview_active) this.unfreeze(); // determine scale factor
var scaleX = this.params.width / this.params.dest_width; var scaleY = this.params.height / this.params.dest_height; // must unflip container as preview canvas will be pre-flipped
this.unflip(); // calc final size of image
var final_width = params.crop_width || params.dest_width; var final_height = params.crop_height || params.dest_height; // create canvas for holding preview
var preview_canvas = document.createElement('canvas'); preview_canvas.width = final_width; preview_canvas.height = final_height; var preview_context = preview_canvas.getContext('2d'); // save for later use
this.preview_canvas = preview_canvas; this.preview_context = preview_context; // scale for preview size
if ((scaleX != 1.0) || (scaleY != 1.0)) { preview_canvas.style.webkitTransformOrigin = '0px 0px'; preview_canvas.style.mozTransformOrigin = '0px 0px'; preview_canvas.style.msTransformOrigin = '0px 0px'; preview_canvas.style.oTransformOrigin = '0px 0px'; preview_canvas.style.transformOrigin = '0px 0px'; preview_canvas.style.webkitTransform = 'scaleX('+scaleX+') scaleY('+scaleY+')'; preview_canvas.style.mozTransform = 'scaleX('+scaleX+') scaleY('+scaleY+')'; preview_canvas.style.msTransform = 'scaleX('+scaleX+') scaleY('+scaleY+')'; preview_canvas.style.oTransform = 'scaleX('+scaleX+') scaleY('+scaleY+')'; preview_canvas.style.transform = 'scaleX('+scaleX+') scaleY('+scaleY+')'; } // take snapshot, but fire our own callback
this.snap( function() { // add preview image to dom, adjust for crop
preview_canvas.style.position = 'relative'; preview_canvas.style.left = '' + self.container.scrollLeft + 'px'; preview_canvas.style.top = '' + self.container.scrollTop + 'px'; self.container.insertBefore( preview_canvas, self.peg ); self.container.style.overflow = 'hidden'; // set flag for user capture (use preview)
self.preview_active = true; }, preview_canvas ); }, unfreeze: function() { // cancel preview and resume live video feed
if (this.preview_active) { // remove preview canvas
this.container.removeChild( this.preview_canvas ); delete this.preview_context; delete this.preview_canvas; // unflag
this.preview_active = false; // re-flip if we unflipped before
this.flip(); } }, flip: function() { // flip container horiz (mirror mode) if desired
if (this.params.flip_horiz) { var sty = this.container.style; sty.webkitTransform = 'scaleX(-1)'; sty.mozTransform = 'scaleX(-1)'; sty.msTransform = 'scaleX(-1)'; sty.oTransform = 'scaleX(-1)'; sty.transform = 'scaleX(-1)'; sty.filter = 'FlipH'; sty.msFilter = 'FlipH'; } }, unflip: function() { // unflip container horiz (mirror mode) if desired
if (this.params.flip_horiz) { var sty = this.container.style; sty.webkitTransform = 'scaleX(1)'; sty.mozTransform = 'scaleX(1)'; sty.msTransform = 'scaleX(1)'; sty.oTransform = 'scaleX(1)'; sty.transform = 'scaleX(1)'; sty.filter = ''; sty.msFilter = ''; } }, savePreview: function(user_callback, user_canvas) { // save preview freeze and fire user callback
var params = this.params; var canvas = this.preview_canvas; var context = this.preview_context; // render to user canvas if desired
if (user_canvas) { var user_context = user_canvas.getContext('2d'); user_context.drawImage( canvas, 0, 0 ); } // fire user callback if desired
user_callback( user_canvas ? null : canvas.toDataURL('image/' + params.image_format, params.jpeg_quality / 100 ), canvas, context ); // remove preview
this.unfreeze(); }, snap: function(user_callback, user_canvas) { // take snapshot and return image data uri
var self = this; var params = this.params; if (!this.loaded) return this.dispatch('error', "Webcam is not loaded yet"); // if (!this.live) return this.dispatch('error', "Webcam is not live yet");
if (!user_callback) return this.dispatch('error', "Please provide a callback function or canvas to snap()"); // if we have an active preview freeze, use that
if (this.preview_active) { this.savePreview( user_callback, user_canvas ); return null; } // create offscreen canvas element to hold pixels
var canvas = document.createElement('canvas'); canvas.width = this.params.dest_width; canvas.height = this.params.dest_height; var context = canvas.getContext('2d'); // flip canvas horizontally if desired
if (this.params.flip_horiz) { context.translate( params.dest_width, 0 ); context.scale( -1, 1 ); } // create inline function, called after image load (flash) or immediately (native)
var func = function() { // render image if needed (flash)
if (this.src && this.width && this.height) { context.drawImage(this, 0, 0, params.dest_width, params.dest_height); } // crop if desired
if (params.crop_width && params.crop_height) { var crop_canvas = document.createElement('canvas'); crop_canvas.width = params.crop_width; crop_canvas.height = params.crop_height; var crop_context = crop_canvas.getContext('2d'); crop_context.drawImage( canvas, Math.floor( (params.dest_width / 2) - (params.crop_width / 2) ), Math.floor( (params.dest_height / 2) - (params.crop_height / 2) ), params.crop_width, params.crop_height, 0, 0, params.crop_width, params.crop_height ); // swap canvases
context = crop_context; canvas = crop_canvas; } // render to user canvas if desired
if (user_canvas) { var user_context = user_canvas.getContext('2d'); user_context.drawImage( canvas, 0, 0 ); } // fire user callback if desired
user_callback( user_canvas ? null : canvas.toDataURL('image/' + params.image_format, params.jpeg_quality / 100 ), canvas, context ); }; // grab image frame from userMedia or flash movie
if (this.userMedia) { // native implementation
context.drawImage(this.video, 0, 0, this.params.dest_width, this.params.dest_height); // fire callback right away
func(); } else { // flash fallback
var raw_data = this.getMovie()._snap(); // render to image, fire callback when complete
var img = new Image(); img.onload = func; img.src = 'data:image/'+this.params.image_format+';base64,' + raw_data; } return null; }, configure: function(panel) { // open flash configuration panel -- specify tab name:
// "camera", "privacy", "default", "localStorage", "microphone", "settingsManager"
if (!panel) panel = "camera"; this.getMovie()._configure(panel); }, flashNotify: function(type, msg) { // receive notification from flash about event
switch (type) { case 'flashLoadComplete': // movie loaded successfully
this.loaded = true; this.dispatch('load'); break; case 'cameraLive': // camera is live and ready to snap
this.live = true; this.dispatch('live'); this.flip(); break;
case 'error': // Flash error
this.dispatch('error', msg); break;
default: // catch-all event, just in case
// console.log("webcam flash_notify: " + type + ": " + msg);
break; } }, b64ToUint6: function(nChr) { // convert base64 encoded character to 6-bit integer
// from: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Base64_encoding_and_decoding
return nChr > 64 && nChr < 91 ? nChr - 65 : nChr > 96 && nChr < 123 ? nChr - 71 : nChr > 47 && nChr < 58 ? nChr + 4 : nChr === 43 ? 62 : nChr === 47 ? 63 : 0; },
base64DecToArr: function(sBase64, nBlocksSize) { // convert base64 encoded string to Uintarray
// from: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Base64_encoding_and_decoding
var sB64Enc = sBase64.replace(/[^A-Za-z0-9\+\/]/g, ""), nInLen = sB64Enc.length, nOutLen = nBlocksSize ? Math.ceil((nInLen * 3 + 1 >> 2) / nBlocksSize) * nBlocksSize : nInLen * 3 + 1 >> 2, taBytes = new Uint8Array(nOutLen); for (var nMod3, nMod4, nUint24 = 0, nOutIdx = 0, nInIdx = 0; nInIdx < nInLen; nInIdx++) { nMod4 = nInIdx & 3; nUint24 |= this.b64ToUint6(sB64Enc.charCodeAt(nInIdx)) << 18 - 6 * nMod4; if (nMod4 === 3 || nInLen - nInIdx === 1) { for (nMod3 = 0; nMod3 < 3 && nOutIdx < nOutLen; nMod3++, nOutIdx++) { taBytes[nOutIdx] = nUint24 >>> (16 >>> nMod3 & 24) & 255; } nUint24 = 0; } } return taBytes; }, upload: function(image_data_uri, target_url, callback) { // submit image data to server using binary AJAX
var form_elem_name = this.params.upload_name || 'webcam'; // detect image format from within image_data_uri
var image_fmt = ''; if (image_data_uri.match(/^data\:image\/(\w+)/)) image_fmt = RegExp.$1; else throw "Cannot locate image format in Data URI"; // extract raw base64 data from Data URI
var raw_image_data = image_data_uri.replace(/^data\:image\/\w+\;base64\,/, ''); // contruct use AJAX object
var http = new XMLHttpRequest(); http.open("POST", target_url, true); // setup progress events
if (http.upload && http.upload.addEventListener) { http.upload.addEventListener( 'progress', function(e) { if (e.lengthComputable) { var progress = e.loaded / e.total; Webcam.dispatch('uploadProgress', progress, e); } }, false ); } // completion handler
var self = this; http.onload = function() { if (callback) callback.apply( self, [http.status, http.responseText, http.statusText] ); Webcam.dispatch('uploadComplete', http.status, http.responseText, http.statusText); }; // create a blob and decode our base64 to binary
var blob = new Blob( [ this.base64DecToArr(raw_image_data) ], {type: 'image/'+image_fmt} ); // stuff into a form, so servers can easily receive it as a standard file upload
var form = new FormData(); form.append( form_elem_name, blob, form_elem_name+"."+image_fmt.replace(/e/, '') ); // send data to server
http.send(form); } };
Webcam.init();
if (typeof define === 'function' && define.amd) { define( function() { return Webcam; } ); } else if (typeof module === 'object' && module.exports) { module.exports = Webcam; } else { window.Webcam = Webcam; }
}(window));
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