图书管理之HTML5压缩旋转裁剪图片总结
整体思路 ：
在移动端压缩图片并且上传主要用到filereader、canvas 以及 formdata 这三个h5的api。逻辑并不难。整个过程就是：
（1）用户使用input file上传图片的时候，用filereader读取用户上传的图片数据（base64格式）
（2）把图片数据传入img对象，然后将img绘制到canvas上，再调用canvas.toDataURL对图片进行压缩
（3）利用copper.js组件进行图片的裁剪旋转处理
（4）获取到压缩后的base64格式图片数据，转成二进制塞入formdata，再通过XmlHttpRequest提交formdata。、
说起来好像挺简单，其实还是有些坑的。接下来就直接用代码进行分析：
1）先是获取图片数据，也就是监听input file的change事件，然后获取到上传的文件对象files，将类数组的files转成数组，然后进行forEach遍历。
先了解一个方法 fileReader
2）接着判断文件类型，如果不是图片则不作处理。如果是图片就实例化一个filereader，以base64格式读取上传的文件数据，判断数据长度，如果大于200KB的图片就调用compress方法进行压缩，否则调用upload方法进行上传。
//在我做的项目中并没有判断图片大小进行分别处理
【2】压缩图片
上面做完图片数据的获取后，就可以做compress压缩图片的方法了。而压缩图片也并不是直接把图片绘制到canvas再调用一下toDataURL就行的。
在IOS中，canvas绘制图片是有两个限制的：
首先是图片的大小，如果图片的大小超过两百万像素，图片也是无法绘制到canvas上的，调用drawImage的时候不会报错，但是你用toDataURL获取图片数据的时候获取到的是空的图片数据。
再者就是canvas的大小有限制，如果canvas的大小大于大概五百万像素（即宽高乘积）的时候，不仅图片画不出来，其他什么东西也都是画不出来的。
应对第一种限制，处理办法就是瓦片绘制了。瓦片绘制，也就是将图片分割成多块绘制到canvas上，我代码里的做法是把图片分割成100万像素一块的大小，再绘制到canvas上。
而应对第二种限制，我的处理办法是对图片的宽高进行适当压缩，我代码里为了保险起见，设的上限是四百万像素，如果图片大于四百万像素就压缩到小于四百万像素。四百万像素的图片应该够了，算起来宽高都有2000X2000了。
如此一来就解决了IOS上的两种限制了。
除了上面所述的限制，还有两个坑，一个就是canvas的toDataURL是只能压缩jpg的，当用户上传的图片是png的话，就需要转成 jpg，也就是统一用canvas.toDataURL('image/jpeg', 0.1) ， 类型统一设成jpeg，而压缩比就自己控制了。
另一个就是如果是png转jpg，绘制到canvas上的时候，canvas存在透明区域的话，当转成jpg的时候透明区域会变成黑色，因为 canvas的透明像素默认为rgba(0,0,0,0)，所以转成jpg就变成rgba(0,0,0,1)了，也就是透明背景会变成了黑色。解决办法就 是绘制之前在canvas上铺一层白色的底色。
function compress(img) { var initSize = img.src.length; var width = img.width; var height = img.height; //如果图片大于四百万像素，计算压缩比并将大小压至400万以下 var ratio; if ((ratio = width * height / 4000000)>1) { ratio = Math.sqrt(ratio); width /= ratio; height /= ratio; }else { ratio = 1; } canvas.width = width; canvas.height = height; // 铺底色 ctx.fillStyle = "#fff"; ctx.fillRect(0, 0, canvas.width, canvas.height); //如果图片像素大于100万则使用瓦片绘制 var count; if ((count = width * height / 1000000) > 1) { count = ~~(Math.sqrt(count)+1); //计算要分成多少块瓦片 // 计算每块瓦片的宽和高 var nw = ~~(width / count); var nh = ~~(height / count); tCanvas.width = nw; tCanvas.height = nh; for (var i = 0; i < count; i++) { for (var j = 0; j < count; j++) { tctx.drawImage(img, i * nw * ratio, j * nh * ratio, nw * ratio, nh * ratio, 0, 0, nw, nh); ctx.drawImage(tCanvas, i * nw, j * nh, nw, nh); } } } else { ctx.drawImage(img, 0, 0, width, height); } //进行最小压缩 var ndata = canvas.toDataURL('image/jpeg', 0.1); console.log('压缩前：' + initSize); console.log('压缩后：' + ndata.length); console.log('压缩率：' + ~~(100 * (initSize - ndata.length) / initSize) + "%"); tCanvas.width = tCanvas.height = canvas.width = canvas.height = 0; return ndata; }
//这里是在别人的博客上面找到的方法 有效的解决了 IOS微信图片压缩后数据量翻倍的问题
下面是我的项目代码
<!DOCTYPE html> <html lang="zh-cn"> <head> <!--定义 title keywords description信息 start--> <title>图书管理</title> <meta name="keywords" content=""/> <meta name="description" content=""/> <!--定义 title keywords description信息 end--> <!-- 定义文档类型 视口信息 start--> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> <link rel="stylesheet" type="text/css" href="css/reset.css"/> <link rel="stylesheet" type="text/css" href="css/common.css" /> <meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=0.5, maximum-scale=2.0, user-scalable=yes" /> </head> <body> <div class="main-wrap"> <header class="headerTop"> <h3>我要分享</h3> </header> <div class="bookBg"> <img src="img/bookBg.png" width="640" height="248"> </div> <div class="cont"> <form action="" method="" class="form"> <div class="form-sub"><label>姓名 :</label><input type="text" id="name" class="text"></div> <div class="form-sub mbn"> <label>分类 :</label> <select id="type" class="select"> <option value="1">开发语言</option> <option value="2">数据库</option> <option value="3">操作系统</option> <option value="4">前端</option> <option value="5" selected>综合</option> </select> </div> <div class="form-txt"> <textarea id="word" class="text2">简介</textarea> </div> <ul id="preview"> <li><img src="img/get1.png"></li> <li><img src="img/get.png"><input type="hidden"></li> <li><img src="img/get.png"><input type="hidden"></li> <li><img src="img/get.png"><input type="hidden"></li> <li><img src="img/get.png"><input type="hidden"></li> <li><img src="img/get.png"><input type="hidden"></li> </ul> <button type="button" id="submit" class="button">确认分享</button> </form> </div> <div class="tan tan-co"> <div class="file-box"> <div class="fileTxt"> <label>选取图片：</label> <div> <button>选择文件</button> <input type="file" id="getImg"> </div> </div> <span id="close"></span> </div> <div class="img-wp"></div> <div class="img-btn"> <p> <button class="rotate rotate-L" id="rotate-L"></button> <button class="sure" id="sure"></button> <button class="rotate rotate-R" id="rotate-R"></button> </p> </div> </div> <footer class="footer"> <a href=""><em></em>图书名单</a> <a href=""><em></em>已借图书</a> <a href="" class="cur"><em></em>我要分享</a> </footer> </div> <script type="text/javascript" src="js/jquery-1.11.0.min.js"></script> <script type="text/javascript" src="js/jy.js"></script> <script type="text/javascript" src="js/cropper.js"></script> <script type="text/javascript"> $(function(){ var box=$(".img-wp"); var img=null; var i=null; //var imgURL; function init(){ var w=$(window).width(); var h=$(window).height(); $('.tan-co').width(w).height(h); $('.img-wp').width(w-20).height(h-120); }; init(); $('#preview li:gt(0)').click(function(){ i=$(this).index(); $('.tan').show(); $('#getImg').change(function(){ var files,file,url; files=$(this).prop('files'); if(files.length>0){ file = files[0]; //上传按钮上传的一个对象 if(isImageFile(file)){ //判断是否是图片 url = createObjectURLfun(file); }else{ $('.img-wp').html('您选择的不是图片文件！请重新选择！！'); }; }; startCropper(url,i); }); }); function startCropper(url,i){ //准备裁剪 img=$('<img src="' + url + '">'); box.empty().html(img); //先清空在放置图片 img.cropper({aspectRatio:2/3}); //图片的压缩速率 } $('#sure').click(function(){ if(img){ var c=img.cropper("getCroppedCanvas"); //获得图片base64的数据 var imgsrc=c.toDataURL("image/jpeg",0.5); //base64位的数据 $('#preview li:eq('+i+') img').attr({'src':imgsrc}); $('#preview li:eq('+i+') input').val(imgsrc); $('#getImg').val(''); $('.img-wp').empty(); $('.tan').hide(); img=null; c=null; } }); $('#rotate-L').click(function(){ if(img){ img.cropper("rotate", -90); } }); $('#rotate-R').click(function(){ if(img){ img.cropper("rotate", 90); } }); function isImageFile(file){ //判断是否是图片 if (file.type) { return /^image\/\w+$/.test(file.type); } else { return /\.(jpg|jpeg|png|gif)$/.test(file); } } $('#close').click(function(){ $('#getImg').val(''); $('.img-wp').empty(); $('.tan').hide(); }); $('#submit').click(function(){ var name=$('#name').val(); var book=$('#book').val(); var type=$('#type option:selected').val(); var word=$('#word').val(); var pic1=$('#preview li:eq(1) input').val(); var pic2=$('#preview li:eq(2) input').val(); var pic3=$('#preview li:eq(3) input').val(); var pic4=$('#preview li:eq(4) input').val(); var pic5=$('#preview li:eq(5) input').val(); }); createObjectURLfun = function(file) { if (window.navigator.userAgent.indexOf("Chrome") >= 1 || window.navigator.userAgent.indexOf("Safari") >= 1) { return window.webkitURL.createObjectURL(file); } else { return window.URL.createObjectURL(file); }; }; }); </script> </body> </html>
/*!
* Cropper v0.9.2
* https://github.com/fengyuanchen/cropper
*
* Copyright (c) 2014-2015 Fengyuan Chen and contributors
* Released under the MIT license
*
* Date: 2015-04-18T04:35:01.500Z
*/
(function (factory) {
if (typeof define === 'function' && define.amd) {
// AMD. Register as anonymous module.
define(['jquery'], factory);
} else if (typeof exports === 'object') {
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factory(jQuery);
}
})(function ($) {
'use strict';
var $window = $(window),
$document = $(document),
location = window.location,
// Constants
CROPPER_NAMESPACE = '.cropper',
CROPPER_PREVIEW = 'preview' + CROPPER_NAMESPACE,
// RegExps
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CLASS_HIDE = 'cropper-hide',
CLASS_HIDDEN = 'cropper-hidden',
CLASS_INVISIBLE = 'cropper-invisible',
CLASS_MOVE = 'cropper-move',
CLASS_CROP = 'cropper-crop',
CLASS_DISABLED = 'cropper-disabled',
CLASS_BG = 'cropper-bg',
// Events
EVENT_MOUSE_DOWN = 'mousedown touchstart',
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EVENT_MOUSE_UP = 'mouseup mouseleave touchend touchleave touchcancel',
EVENT_WHEEL = 'wheel mousewheel DOMMouseScroll',
EVENT_DBLCLICK = 'dblclick',
EVENT_RESIZE = 'resize' + CROPPER_NAMESPACE, // Bind to window with namespace
EVENT_BUILD = 'build' + CROPPER_NAMESPACE,
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EVENT_DRAG_START = 'dragstart' + CROPPER_NAMESPACE,
EVENT_DRAG_MOVE = 'dragmove' + CROPPER_NAMESPACE,
EVENT_DRAG_END = 'dragend' + CROPPER_NAMESPACE,
EVENT_ZOOM_IN = 'zoomin' + CROPPER_NAMESPACE,
EVENT_ZOOM_OUT = 'zoomout' + CROPPER_NAMESPACE,
// Supports
SUPPORT_CANVAS = $.isFunction($('<canvas>')[0].getContext),
// Others
sqrt = Math.sqrt,
min = Math.min,
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abs = Math.abs,
sin = Math.sin,
cos = Math.cos,
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args.push(offset);
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return args.slice.apply(obj, args);
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function proxy(fn, context) {
var args = toArray(arguments, 2);
return function () {
return fn.apply(context, args.concat(toArray(arguments)));
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function isCrossOriginURL(url) {
var parts = url.match(/^(https?:)\/\/([^\:\/\?#]+):?(\d*)/i);
return parts && (parts[1] !== location.protocol || parts[2] !== location.hostname || parts[3] !== location.port);
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function inRange(source, target) { //是否在范围内
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function getRotateValue(degree) { //获取旋转的角度
return degree ? 'rotate(' + degree + 'deg)' : 'none';
}
function getRotatedSizes(data, reverse) {
var deg = abs(data.degree) % 180,
arc = (deg > 90 ? (180 - deg) : deg) * Math.PI / 180,
sinArc = sin(arc),
cosArc = cos(arc),
width = data.width,
height = data.height,
aspectRatio = data.aspectRatio,
newWidth,
newHeight;
if (!reverse) { //如果反向的话
newWidth = width * cosArc + height * sinArc;
newHeight = width * sinArc + height * cosArc;
} else {
newWidth = width / (cosArc + sinArc / aspectRatio);
newHeight = newWidth / aspectRatio;
}
return {
width: newWidth,
height: newHeight
};
}
function getSourceCanvas(image, data) {
var canvas = $('<canvas>')[0],
context = canvas.getContext('2d'),
width = data.naturalWidth,
height = data.naturalHeight,
rotate = data.rotate,
rotated = getRotatedSizes({
width: width,
height: height,
degree: rotate
});
if (rotate) {
canvas.width = rotated.width;
canvas.height = rotated.height;
context.save();
context.translate(rotated.width / 2, rotated.height / 2);
context.rotate(rotate * Math.PI / 180);
context.drawImage(image, -width / 2, -height / 2, width, height);
context.restore();
} else {
canvas.width = width;
canvas.height = height;
context.drawImage(image, 0, 0, width, height);
}
return canvas;
}
function Cropper(element, options) {
this.$element = $(element);
this.options = $.extend({}, Cropper.DEFAULTS, $.isPlainObject(options) && options);
this.ready = false;
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this.rotated = false;
this.cropped = false;
this.disabled = false;
this.canvas = null;
this.cropBox = null;
this.load();
}
prototype.load = function (url) {
var options = this.options,
$this = this.$element,
crossOrigin,
bustCacheUrl,
buildEvent,
$clone;
if (!url) {
if ($this.is('img')) {
if (!$this.attr('src')) { //没有src属性 就返回
return;
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url = $this.prop('src');
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//1.添加属性名称该属性就会生效应该使用prop();
//2.是有true,false两个属性使用prop();
//3.其他则使用attr();
} else if ($this.is('canvas') && SUPPORT_CANVAS) { //是画布并且支持画布
url =compress($this[0]);
}
}
if (!url) { //如果找不到地址 就返回
return;
}
buildEvent = $.Event(EVENT_BUILD);
$this.one(EVENT_BUILD, options.build).trigger(buildEvent); // Only trigger once
if (buildEvent.isDefaultPrevented()) {
return;
}
if (options.checkImageOrigin && isCrossOriginURL(url)) {
crossOrigin = 'anonymous';
if (!$this.prop('crossOrigin')) { // Only when there was not a "crossOrigin" property 只有当没有“crossOrigin”属性
bustCacheUrl = addTimestamp(url); // Bust cache (#148)
}
}
this.$clone = $clone = $('<img>');
$clone.one('load', $.proxy(function () {
var naturalWidth = $clone.prop('naturalWidth') || $clone.width(),
naturalHeight = $clone.prop('naturalHeight') || $clone.height();
this.image = {
naturalWidth: naturalWidth,
naturalHeight: naturalHeight,
aspectRatio: naturalWidth / naturalHeight,
rotate: 0
};
this.url = url;
this.ready = true;
this.build();
}, this)).one('error', function () {
$clone.remove();
}).attr({
src: bustCacheUrl || url,
crossOrigin: crossOrigin
});
// Hide and insert into the document
$clone.addClass(CLASS_HIDE).insertAfter($this);
};
prototype.build = function () {
var $this = this.$element,
$clone = this.$clone,
options = this.options,
$cropper,
$cropBox;
if (!this.ready) {
return;
}
if (this.built) {
this.unbuild();
}
// Create cropper elements
this.$cropper = $cropper = $(Cropper.TEMPLATE);
// Hide the original image
$this.addClass(CLASS_HIDDEN);
// Show the clone iamge
$clone.removeClass(CLASS_HIDE);
this.$container = $this.parent().append($cropper);
this.$canvas = $cropper.find('.cropper-canvas').append($clone);
this.$dragBox = $cropper.find('.cropper-drag-box');
this.$cropBox = $cropBox = $cropper.find('.cropper-crop-box');
this.$viewBox = $cropper.find('.cropper-view-box');
this.addListeners();
this.initPreview();
// Format aspect ratio
options.aspectRatio = num(options.aspectRatio) || NaN; // 0 -> NaN
if (options.autoCrop) {
this.cropped = true;
if (options.modal) {
this.$dragBox.addClass(CLASS_MODAL);
}
} else {
$cropBox.addClass(CLASS_HIDDEN);
}
if (options.background) {
$cropper.addClass(CLASS_BG);
}
if (!options.highlight) {
$cropBox.find('.cropper-face').addClass(CLASS_INVISIBLE);
}
if (!options.guides) {
$cropBox.find('.cropper-dashed').addClass(CLASS_HIDDEN);
}
if (!options.movable) {
$cropBox.find('.cropper-face').data('drag', 'move');
}
if (!options.resizable) {
$cropBox.find('.cropper-line, .cropper-point').addClass(CLASS_HIDDEN);
}
this.setDragMode(options.dragCrop ? 'crop' : 'move');
this.built = true;
this.render();
$this.one(EVENT_BUILT, options.built).trigger(EVENT_BUILT); // Only trigger once
};
prototype.unbuild = function () {
if (!this.built) {
return;
}
this.built = false;
this.container = null;
this.canvas = null;
this.cropBox = null; // This is necessary when replace
this.removeListeners();
this.resetPreview();
this.$preview = null;
this.$viewBox = null;
this.$cropBox = null;
this.$dragBox = null;
this.$canvas = null;
this.$container = null;
this.$cropper.remove();
this.$cropper = null;
};
$.extend(prototype, {
render: function () {
this.initContainer();
this.initCanvas();
this.initCropBox();
this.renderCanvas();
if (this.cropped) {
this.renderCropBox();
}
},
initContainer: function () {
var $this = this.$element,
$container = this.$container,
$cropper = this.$cropper,
options = this.options;
$cropper.addClass(CLASS_HIDDEN);
$this.removeClass(CLASS_HIDDEN);
$cropper.css((this.container = {
width: max($container.width(), num(options.minContainerWidth) || 200),
height: max($container.height(), num(options.minContainerHeight) || 100)
}));
$this.addClass(CLASS_HIDDEN);
$cropper.removeClass(CLASS_HIDDEN);
},
// image box (wrapper)
initCanvas: function () {
var container = this.container,
containerWidth = container.width,
containerHeight = container.height,
image = this.image,
aspectRatio = image.aspectRatio,
canvas = {
aspectRatio: aspectRatio,
width: containerWidth,
height: containerHeight
};
if (containerHeight * aspectRatio > containerWidth) {
canvas.height = containerWidth / aspectRatio;
} else {
canvas.width = containerHeight * aspectRatio;
}
canvas.oldLeft = canvas.left = (containerWidth - canvas.width) / 2;
canvas.oldTop = canvas.top = (containerHeight - canvas.height) / 2;
this.canvas = canvas;
this.limitCanvas(true, true);
this.initialImage = $.extend({}, image);
this.initialCanvas = $.extend({}, canvas);
},
limitCanvas: function (size, position) {
var options = this.options,
strict = options.strict,
container = this.container,
containerWidth = container.width,
containerHeight = container.height,
canvas = this.canvas,
aspectRatio = canvas.aspectRatio,
cropBox = this.cropBox,
cropped = this.cropped && cropBox,
minCanvasWidth,
minCanvasHeight;
if (size) {
minCanvasWidth = num(options.minCanvasWidth) || 0;
minCanvasHeight = num(options.minCanvasHeight) || 0;
if (minCanvasWidth) {
if (strict) {
minCanvasWidth = max(cropped ? cropBox.width : containerWidth, minCanvasWidth);
}
minCanvasHeight = minCanvasWidth / aspectRatio;
} else if (minCanvasHeight) {
if (strict) {
minCanvasHeight = max(cropped ? cropBox.height : containerHeight, minCanvasHeight);
}
minCanvasWidth = minCanvasHeight * aspectRatio;
} else if (strict) {
if (cropped) {
minCanvasWidth = cropBox.width;
minCanvasHeight = cropBox.height;
if (minCanvasHeight * aspectRatio > minCanvasWidth) {
minCanvasWidth = minCanvasHeight * aspectRatio;
} else {
minCanvasHeight = minCanvasWidth / aspectRatio;
}
} else {
minCanvasWidth = containerWidth;
minCanvasHeight = containerHeight;
if (minCanvasHeight * aspectRatio > minCanvasWidth) {
minCanvasHeight = minCanvasWidth / aspectRatio;
} else {
minCanvasWidth = minCanvasHeight * aspectRatio;
}
}
}
$.extend(canvas, {
minWidth: minCanvasWidth,
minHeight: minCanvasHeight,
maxWidth: Infinity,
maxHeight: Infinity
});
}
if (position) {
if (strict) {
if (cropped) {
canvas.minLeft = min(cropBox.left, (cropBox.left + cropBox.width) - canvas.width);
canvas.minTop = min(cropBox.top, (cropBox.top + cropBox.height) - canvas.height);
canvas.maxLeft = cropBox.left;
canvas.maxTop = cropBox.top;
} else {
canvas.minLeft = min(0, containerWidth - canvas.width);
canvas.minTop = min(0, containerHeight - canvas.height);
canvas.maxLeft = max(0, containerWidth - canvas.width);
canvas.maxTop = max(0, containerHeight - canvas.height);
}
} else {
canvas.minLeft = -canvas.width;
canvas.minTop = -canvas.height;
canvas.maxLeft = containerWidth;
canvas.maxTop = containerHeight;
}
}
},
renderCanvas: function (changed) {
var options = this.options,
canvas = this.canvas,
image = this.image,
aspectRatio,
rotated;
if (this.rotated) {
this.rotated = false;
// Computes rotatation sizes with image sizes
rotated = getRotatedSizes({
width: image.width,
height: image.height,
degree: image.rotate
});
aspectRatio = rotated.width / rotated.height;
if (aspectRatio !== canvas.aspectRatio) {
canvas.left -= (rotated.width - canvas.width) / 2;
canvas.top -= (rotated.height - canvas.height) / 2;
canvas.width = rotated.width;
canvas.height = rotated.height;
canvas.aspectRatio = aspectRatio;
this.limitCanvas(true, false);
}
}
if (canvas.width > canvas.maxWidth || canvas.width < canvas.minWidth) {
canvas.left = canvas.oldLeft;
}
if (canvas.height > canvas.maxHeight || canvas.height < canvas.minHeight) {
canvas.top = canvas.oldTop;
}
canvas.width = min(max(canvas.width, canvas.minWidth), canvas.maxWidth);
canvas.height = min(max(canvas.height, canvas.minHeight), canvas.maxHeight);
this.limitCanvas(false, true);
canvas.oldLeft = canvas.left = min(max(canvas.left, canvas.minLeft), canvas.maxLeft);
canvas.oldTop = canvas.top = min(max(canvas.top, canvas.minTop), canvas.maxTop);
this.$canvas.css({
width: canvas.width,
height: canvas.height,
left: canvas.left,
top: canvas.top
});
this.renderImage();
if (this.cropped && options.strict && !inRange(this.container, canvas)) {
this.limitCropBox(true, true);
}
if (changed) {
this.output();
}
},
renderImage: function () {
var canvas = this.canvas,
image = this.image,
reversed;
if (image.rotate) {
reversed = getRotatedSizes({
width: canvas.width,
height: canvas.height,
degree: image.rotate,
aspectRatio: image.aspectRatio
}, true);
}
$.extend(image, reversed ? {
width: reversed.width,
height: reversed.height,
left: (canvas.width - reversed.width) / 2,
top: (canvas.height - reversed.height) / 2
} : {
width: canvas.width,
height: canvas.height,
left: 0,
top: 0
});
this.$clone.css({
width: image.width,
height: image.height,
marginLeft: image.left,
marginTop: image.top,
transform: getRotateValue(image.rotate)
});
},
initCropBox: function () {
var options = this.options,
canvas = this.canvas,
aspectRatio = options.aspectRatio,
autoCropArea = num(options.autoCropArea) || 0.8,
cropBox = {
width: canvas.width,
height: canvas.height
};
if (aspectRatio) {
if (canvas.height * aspectRatio > canvas.width) {
cropBox.height = cropBox.width / aspectRatio;
} else {
cropBox.width = cropBox.height * aspectRatio;
}
}
this.cropBox = cropBox;
this.limitCropBox(true, true);
// Initialize auto crop area
cropBox.width = min(max(cropBox.width, cropBox.minWidth), cropBox.maxWidth);
cropBox.height = min(max(cropBox.height, cropBox.minHeight), cropBox.maxHeight);
// The width of auto crop area must large than "minWidth", and the height too. (#164)
cropBox.width = max(cropBox.minWidth, cropBox.width * autoCropArea);
cropBox.height = max(cropBox.minHeight, cropBox.height * autoCropArea);
cropBox.oldLeft = cropBox.left = canvas.left + (canvas.width - cropBox.width) / 2;
cropBox.oldTop = cropBox.top = canvas.top + (canvas.height - cropBox.height) / 2;
this.initialCropBox = $.extend({}, cropBox);
},
limitCropBox: function (size, position) {
var options = this.options,
strict = options.strict,
container = this.container,
containerWidth = container.width,
containerHeight = container.height,
canvas = this.canvas,
cropBox = this.cropBox,
aspectRatio = options.aspectRatio,
minCropBoxWidth,
minCropBoxHeight;
if (size) {
minCropBoxWidth = num(options.minCropBoxWidth) || 0;
minCropBoxHeight = num(options.minCropBoxHeight) || 0;
// min/maxCropBoxWidth/Height must less than conatiner width/height
cropBox.minWidth = min(containerWidth, minCropBoxWidth);
cropBox.minHeight = min(containerHeight, minCropBoxHeight);
cropBox.maxWidth = min(containerWidth, strict ? canvas.width : containerWidth);
cropBox.maxHeight = min(containerHeight, strict ? canvas.height : containerHeight);
if (aspectRatio) {
// compare crop box size with container first
if (cropBox.maxHeight * aspectRatio > cropBox.maxWidth) {
cropBox.minHeight = cropBox.minWidth / aspectRatio;
cropBox.maxHeight = cropBox.maxWidth / aspectRatio;
} else {
cropBox.minWidth = cropBox.minHeight * aspectRatio;
cropBox.maxWidth = cropBox.maxHeight * aspectRatio;
}
}
// The "minWidth" must be less than "maxWidth", and the "minHeight" too.
cropBox.minWidth = min(cropBox.maxWidth, cropBox.minWidth);
cropBox.minHeight = min(cropBox.maxHeight, cropBox.minHeight);
}
if (position) {
if (strict) {
cropBox.minLeft = max(0, canvas.left);
cropBox.minTop = max(0, canvas.top);
cropBox.maxLeft = min(containerWidth, canvas.left + canvas.width) - cropBox.width;
cropBox.maxTop = min(containerHeight, canvas.top + canvas.height) - cropBox.height;
} else {
cropBox.minLeft = 0;
cropBox.minTop = 0;
cropBox.maxLeft = containerWidth - cropBox.width;
cropBox.maxTop = containerHeight - cropBox.height;
}
}
},
renderCropBox: function () {
var options = this.options,
container = this.container,
containerWidth = container.width,
containerHeight = container.height,
$cropBox = this.$cropBox,
cropBox = this.cropBox;
if (cropBox.width > cropBox.maxWidth || cropBox.width < cropBox.minWidth) {
cropBox.left = cropBox.oldLeft;
}
if (cropBox.height > cropBox.maxHeight || cropBox.height < cropBox.minHeight) {
cropBox.top = cropBox.oldTop;
}
cropBox.width = min(max(cropBox.width, cropBox.minWidth), cropBox.maxWidth);
cropBox.height = min(max(cropBox.height, cropBox.minHeight), cropBox.maxHeight);
this.limitCropBox(false, true);
cropBox.oldLeft = cropBox.left = min(max(cropBox.left, cropBox.minLeft), cropBox.maxLeft);
cropBox.oldTop = cropBox.top = min(max(cropBox.top, cropBox.minTop), cropBox.maxTop);
if (options.movable) {
$cropBox.find('.cropper-face').data('drag', (cropBox.width === containerWidth && cropBox.height === containerHeight) ? 'move' : 'all');
}
$cropBox.css({
width: cropBox.width,
height: cropBox.height,
left: cropBox.left,
top: cropBox.top
});
if (this.cropped && options.strict && !inRange(container, this.canvas)) {
this.limitCanvas(true, true);
}
if (!this.disabled) {
this.output();
}
},
output: function () {
var options = this.options;
this.preview();
if (options.crop) {
options.crop.call(this.$element, this.getData());
}
}
});
prototype.initPreview = function () {
var url = this.url;
this.$preview = $(this.options.preview);
this.$viewBox.html('<img src="' + url + '">');
// Override img element styles
// Add `display:block` to avoid margin top issue (Occur only when margin-top <= -height)
this.$preview.each(function () {
var $this = $(this);
$this.data(CROPPER_PREVIEW, {
width: $this.width(),
height: $this.height(),
original: $this.html()
}).html('<img src="' + url + '" style="display:block;width:100%;min-width:0!important;min-height:0!important;max-width:none!important;max-height:none!important;image-orientation: 0deg!important">');
});
};
prototype.resetPreview = function () {
this.$preview.each(function () {
var $this = $(this);
$this.html($this.data(CROPPER_PREVIEW).original).removeData(CROPPER_PREVIEW);
});
};
prototype.preview = function () {
var image = this.image,
canvas = this.canvas,
cropBox = this.cropBox,
width = image.width,
height = image.height,
left = cropBox.left - canvas.left - image.left,
top = cropBox.top - canvas.top - image.top,
rotate = image.rotate;
if (!this.cropped || this.disabled) {
return;
}
this.$viewBox.find('img').css({
width: width,
height: height,
marginLeft: -left,
marginTop: -top,
transform: getRotateValue(rotate)
});
this.$preview.each(function () {
var $this = $(this),
data = $this.data(CROPPER_PREVIEW),
ratio = data.width / cropBox.width,
newWidth = data.width,
newHeight = cropBox.height * ratio;
if (newHeight > data.height) {
ratio = data.height / cropBox.height;
newWidth = cropBox.width * ratio;
newHeight = data.height;
}
$this.width(newWidth).height(newHeight).find('img').css({
width: width * ratio,
height: height * ratio,
marginLeft: -left * ratio,
marginTop: -top * ratio,
transform: getRotateValue(rotate)
});
});
};
prototype.addListeners = function () {
var options = this.options;
this.$element.on(EVENT_DRAG_START, options.dragstart).on(EVENT_DRAG_MOVE, options.dragmove).on(EVENT_DRAG_END, options.dragend).on(EVENT_ZOOM_IN, options.zoomin).on(EVENT_ZOOM_OUT, options.zoomout);
this.$cropper.on(EVENT_MOUSE_DOWN, $.proxy(this.dragstart, this)).on(EVENT_DBLCLICK, $.proxy(this.dblclick, this));
if (options.zoomable && options.mouseWheelZoom) {
this.$cropper.on(EVENT_WHEEL, $.proxy(this.wheel, this));
}
$document.on(EVENT_MOUSE_MOVE, (this._dragmove = proxy(this.dragmove, this))).on(EVENT_MOUSE_UP, (this._dragend = proxy(this.dragend, this)));
if (options.responsive) {
$window.on(EVENT_RESIZE, (this._resize = proxy(this.resize, this)));
}
};
prototype.removeListeners = function () {
var options = this.options;
this.$element.off(EVENT_DRAG_START, options.dragstart).off(EVENT_DRAG_MOVE, options.dragmove).off(EVENT_DRAG_END, options.dragend).off(EVENT_ZOOM_IN, options.zoomin).off(EVENT_ZOOM_OUT, options.zoomout);
this.$cropper.off(EVENT_MOUSE_DOWN, this.dragstart).off(EVENT_DBLCLICK, this.dblclick);
if (options.zoomable && options.mouseWheelZoom) {
this.$cropper.off(EVENT_WHEEL, this.wheel);
}
$document.off(EVENT_MOUSE_MOVE, this._dragmove).off(EVENT_MOUSE_UP, this._dragend);
if (options.responsive) {
$window.off(EVENT_RESIZE, this._resize);
}
};
$.extend(prototype, {
resize: function () {
var $container = this.$container,
container = this.container,
canvasData,
cropBoxData,
ratio;
if (this.disabled) {
return;
}
ratio = $container.width() / container.width;
if (ratio !== 1 || $container.height() !== container.height) {
canvasData = this.getCanvasData();
cropBoxData = this.getCropBoxData();
this.render();
this.setCanvasData($.each(canvasData, function (i, n) {
canvasData[i] = n * ratio;
}));
this.setCropBoxData($.each(cropBoxData, function (i, n) {
cropBoxData[i] = n * ratio;
}));
}
},
dblclick: function () {
if (this.disabled) {
return;
}
if (this.$dragBox.hasClass(CLASS_CROP)) {
this.setDragMode('move');
} else {
this.setDragMode('crop');
}
},
wheel: function (event) {
var e = event.originalEvent,
delta = 1;
if (this.disabled) {
return;
}
event.preventDefault();
if (e.deltaY) {
delta = e.deltaY > 0 ? 1 : -1;
} else if (e.wheelDelta) {
delta = -e.wheelDelta / 120;
} else if (e.detail) {
delta = e.detail > 0 ? 1 : -1;
}
this.zoom(-delta * 0.1);
},
dragstart: function (event) {
var options = this.options,
originalEvent = event.originalEvent,
touches = originalEvent && originalEvent.touches,
e = event,
dragType,
dragStartEvent,
touchesLength;
if (this.disabled) {
return;
}
if (touches) {
touchesLength = touches.length;
if (touchesLength > 1) {
if (options.zoomable && options.touchDragZoom && touchesLength === 2) {
e = touches[1];
this.startX2 = e.pageX;
this.startY2 = e.pageY;
dragType = 'zoom';
} else {
return;
}
}
e = touches[0];
}
dragType = dragType || $(e.target).data('drag');
if (REGEXP_DRAG_TYPES.test(dragType)) {
event.preventDefault();
dragStartEvent = $.Event(EVENT_DRAG_START, {
originalEvent: originalEvent,
dragType: dragType
});
this.$element.trigger(dragStartEvent);
if (dragStartEvent.isDefaultPrevented()) {
return;
}
this.dragType = dragType;
this.cropping = false;
this.startX = e.pageX;
this.startY = e.pageY;
if (dragType === 'crop') {
this.cropping = true;
this.$dragBox.addClass(CLASS_MODAL);
}
}
},
dragmove: function (event) {
var options = this.options,
originalEvent = event.originalEvent,
touches = originalEvent && originalEvent.touches,
e = event,
dragType = this.dragType,
dragMoveEvent,
touchesLength;
if (this.disabled) {
return;
}
if (touches) {
touchesLength = touches.length;
if (touchesLength > 1) {
if (options.zoomable && options.touchDragZoom && touchesLength === 2) {
e = touches[1];
this.endX2 = e.pageX;
this.endY2 = e.pageY;
} else {
return;
}
}
e = touches[0];
}
if (dragType) {
event.preventDefault();
dragMoveEvent = $.Event(EVENT_DRAG_MOVE, {
originalEvent: originalEvent,
dragType: dragType
});
this.$element.trigger(dragMoveEvent);
if (dragMoveEvent.isDefaultPrevented()) {
return;
}
this.endX = e.pageX;
this.endY = e.pageY;
this.change();
}
},
dragend: function (event) {
var dragType = this.dragType,
dragEndEvent;
if (this.disabled) {
return;
}
if (dragType) {
event.preventDefault();
dragEndEvent = $.Event(EVENT_DRAG_END, {
originalEvent: event.originalEvent,
dragType: dragType
});
this.$element.trigger(dragEndEvent);
if (dragEndEvent.isDefaultPrevented()) {
return;
}
if (this.cropping) {
this.cropping = false;
this.$dragBox.toggleClass(CLASS_MODAL, this.cropped && this.options.modal);
}
this.dragType = '';
}
}
});
$.extend(prototype, {
reset: function () {
if (!this.built || this.disabled) {
return;
}
this.image = $.extend({}, this.initialImage);
this.canvas = $.extend({}, this.initialCanvas);
this.renderCanvas();
if (this.cropped) {
this.cropBox = $.extend({}, this.initialCropBox);
this.renderCropBox();
}
},
clear: function () {
if (!this.cropped || this.disabled) {
return;
}
$.extend(this.cropBox, {
left: 0,
top: 0,
width: 0,
height: 0
});
this.cropped = false;
this.renderCropBox();
this.limitCanvas();
this.renderCanvas(); // Render canvas after render crop box
this.$dragBox.removeClass(CLASS_MODAL);
this.$cropBox.addClass(CLASS_HIDDEN);
},
destroy: function () {
var $this = this.$element;
if (this.ready) {
this.unbuild();
$this.removeClass(CLASS_HIDDEN);
} else {
this.$clone.off('load').remove();
}
$this.removeData('cropper');
},
replace: function (url) {
if (!this.disabled && url) {
this.load(url);
}
},
enable: function () {
if (this.built) {
this.disabled = false;
this.$cropper.removeClass(CLASS_DISABLED);
}
},
disable: function () {
if (this.built) {
this.disabled = true;
this.$cropper.addClass(CLASS_DISABLED);
}
},
move: function (offsetX, offsetY) {
var canvas = this.canvas;
if (this.built && !this.disabled && isNumber(offsetX) && isNumber(offsetY)) {
canvas.left += offsetX;
canvas.top += offsetY;
this.renderCanvas(true);
}
},
zoom: function (delta) {
var canvas = this.canvas,
zoomEvent,
width,
height;
delta = num(delta);
if (delta && this.built && !this.disabled && this.options.zoomable) {
zoomEvent = delta > 0 ? $.Event(EVENT_ZOOM_IN) : $.Event(EVENT_ZOOM_OUT);
this.$element.trigger(zoomEvent);
if (zoomEvent.isDefaultPrevented()) {
return;
}
delta = delta <= -1 ? 1 / (1 - delta) : delta <= 1 ? (1 + delta) : delta;
width = canvas.width * delta;
height = canvas.height * delta;
canvas.left -= (width - canvas.width) / 2;
canvas.top -= (height - canvas.height) / 2;
canvas.width = width;
canvas.height = height;
this.renderCanvas(true);
this.setDragMode('move');
}
},
rotate: function (degree) {
var image = this.image;
degree = num(degree);
if (degree && this.built && !this.disabled && this.options.rotatable) {
image.rotate = (image.rotate + degree) % 360;
this.rotated = true;
this.renderCanvas(true);
}
},
getData: function () {
var cropBox = this.cropBox,
canvas = this.canvas,
image = this.image,
ratio,
data;
if (this.built && this.cropped) {
data = {
x: cropBox.left - canvas.left,
y: cropBox.top - canvas.top,
width: cropBox.width,
height: cropBox.height
};
ratio = image.width / image.naturalWidth;
$.each(data, function (i, n) {
n = n / ratio;
data[i] = n;
});
} else {
data = {
x: 0,
y: 0,
width: 0,
height: 0
};
}
data.rotate = image.rotate;
return data;
},
getContainerData: function () {
return this.built ? this.container : {};
},
getImageData: function () {
return this.ready ? this.image : {};
},
getCanvasData: function () {
var canvas = this.canvas,
data;
if (this.built) {
data = {
left: canvas.left,
top: canvas.top,
width: canvas.width,
height: canvas.height
};
}
return data || {};
},
setCanvasData: function (data) {
var canvas = this.canvas,
aspectRatio = canvas.aspectRatio;
if (this.built && !this.disabled && $.isPlainObject(data)) {
if (isNumber(data.left)) {
canvas.left = data.left;
}
if (isNumber(data.top)) {
canvas.top = data.top;
}
if (isNumber(data.width)) {
canvas.width = data.width;
canvas.height = data.width / aspectRatio;
} else if (isNumber(data.height)) {
canvas.height = data.height;
canvas.width = data.height * aspectRatio;
}
this.renderCanvas(true);
}
},
getCropBoxData: function () {
var cropBox = this.cropBox,
data;
if (this.built && this.cropped) {
data = {
left: cropBox.left,
top: cropBox.top,
width: cropBox.width,
height: cropBox.height
};
}
return data || {};
},
setCropBoxData: function (data) {
var cropBox = this.cropBox,
aspectRatio = this.options.aspectRatio;
if (this.built && this.cropped && !this.disabled && $.isPlainObject(data)) {
if (isNumber(data.left)) {
cropBox.left = data.left;
}
if (isNumber(data.top)) {
cropBox.top = data.top;
}
if (aspectRatio) {
if (isNumber(data.width)) {
cropBox.width = data.width;
cropBox.height = cropBox.width / aspectRatio;
} else if (isNumber(data.height)) {
cropBox.height = data.height;
cropBox.width = cropBox.height * aspectRatio;
}
} else {
if (isNumber(data.width)) {
cropBox.width = data.width;
}
if (isNumber(data.height)) {
cropBox.height = data.height;
}
}
this.renderCropBox();
}
},
getCroppedCanvas: function (options) { //获取画布
var originalWidth,
originalHeight,
canvasWidth,
canvasHeight,
scaledWidth,
scaledHeight,
scaledRatio,
aspectRatio,
canvas,
context,
data;
if (!this.built || !this.cropped || !SUPPORT_CANVAS) {
return;
}
if (!$.isPlainObject(options)) {
options = {};
}
data = this.getData();
originalWidth = data.width;
originalHeight = data.height;
aspectRatio = originalWidth / originalHeight;
if ($.isPlainObject(options)) {
scaledWidth = options.width;
scaledHeight = options.height;
if (scaledWidth) {
scaledHeight = scaledWidth / aspectRatio;
scaledRatio = scaledWidth / originalWidth;
} else if (scaledHeight) {
scaledWidth = scaledHeight * aspectRatio;
scaledRatio = scaledHeight / originalHeight;
}
}
canvasWidth = scaledWidth || originalWidth;
canvasHeight = scaledHeight || originalHeight;
canvas = $('<canvas>')[0];
canvas.width = canvasWidth;
canvas.height = canvasHeight;
context = canvas.getContext('2d');
if (options.fillColor) {
context.fillStyle = options.fillColor;
context.fillRect(0, 0, canvasWidth, canvasHeight);
}
// https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D.drawImage
context.drawImage.apply(context, (function () {
var source = getSourceCanvas(this.$clone[0], this.image),
sourceWidth = source.width,
sourceHeight = source.height,
args = [source],
srcX = data.x, // source canvas
srcY = data.y,
srcWidth,
srcHeight,
dstX, // destination canvas
dstY,
dstWidth,
dstHeight;
if (srcX <= -originalWidth || srcX > sourceWidth) {
srcX = srcWidth = dstX = dstWidth = 0;
} else if (srcX <= 0) {
dstX = -srcX;
srcX = 0;
srcWidth = dstWidth = min(sourceWidth, originalWidth + srcX);
} else if (srcX <= sourceWidth) {
dstX = 0;
srcWidth = dstWidth = min(originalWidth, sourceWidth - srcX);
}
if (srcWidth <= 0 || srcY <= -originalHeight || srcY > sourceHeight) {
srcY = srcHeight = dstY = dstHeight = 0;
} else if (srcY <= 0) {
dstY = -srcY;
srcY = 0;
srcHeight = dstHeight = min(sourceHeight, originalHeight + srcY);
} else if (srcY <= sourceHeight) {
dstY = 0;
srcHeight = dstHeight = min(originalHeight, sourceHeight - srcY);
}
args.push(srcX, srcY, srcWidth, srcHeight);
// Scale destination sizes
if (scaledRatio) {
dstX *= scaledRatio;
dstY *= scaledRatio;
dstWidth *= scaledRatio;
dstHeight *= scaledRatio;
}
// Avoid "IndexSizeError" in IE and Firefox
if (dstWidth > 0 && dstHeight > 0) {
args.push(dstX, dstY, dstWidth, dstHeight);
}
return args;
}).call(this));
return canvas;
},
setAspectRatio: function (aspectRatio) {
var options = this.options;
if (!this.disabled && !isUndefined(aspectRatio)) {
options.aspectRatio = num(aspectRatio) || NaN; // 0 -> NaN
if (this.built) {
this.initCropBox();
if (this.cropped) {
this.renderCropBox();
}
}
}
},
setDragMode: function (mode) {
var $dragBox = this.$dragBox,
cropable = false,
movable = false;
if (!this.ready || this.disabled) {
return;
}
switch (mode) {
case 'crop':
if (this.options.dragCrop) {
cropable = true;
$dragBox.data('drag', mode);
} else {
movable = true;
}
break;
case 'move':
movable = true;
$dragBox.data('drag', mode);
break;
default:
$dragBox.removeData('drag');
}
$dragBox.toggleClass(CLASS_CROP, cropable).toggleClass(CLASS_MOVE, movable);
}
});
prototype.change = function () {
var dragType = this.dragType,
options = this.options,
canvas = this.canvas,
container = this.container,
cropBox = this.cropBox,
width = cropBox.width,
height = cropBox.height,
left = cropBox.left,
top = cropBox.top,
right = left + width,
bottom = top + height,
minLeft = 0,
minTop = 0,
maxWidth = container.width,
maxHeight = container.height,
renderable = true,
aspectRatio = options.aspectRatio,
range = {
x: this.endX - this.startX,
y: this.endY - this.startY
},
offset;
if (options.strict) {
minLeft = cropBox.minLeft;
minTop = cropBox.minTop;
maxWidth = minLeft + min(container.width, canvas.width);
maxHeight = minTop + min(container.height, canvas.height);
}
if (aspectRatio) {
range.X = range.y * aspectRatio;
range.Y = range.x / aspectRatio;
}
switch (dragType) {
// Move cropBox
case 'all':
left += range.x;
top += range.y;
break;
// Resize cropBox
case 'e':
if (range.x >= 0 && (right >= maxWidth || aspectRatio && (top <= minTop || bottom >= maxHeight))) {
renderable = false;
break;
}
width += range.x;
if (aspectRatio) {
height = width / aspectRatio;
top -= range.Y / 2;
}
if (width < 0) {
dragType = 'w';
width = 0;
}
break;
case 'n':
if (range.y <= 0 && (top <= minTop || aspectRatio && (left <= minLeft || right >= maxWidth))) {
renderable = false;
break;
}
height -= range.y;
top += range.y;
if (aspectRatio) {
width = height * aspectRatio;
left += range.X / 2;
}
if (height < 0) {
dragType = 's';
height = 0;
}
break;
case 'w':
if (range.x <= 0 && (left <= minLeft || aspectRatio && (top <= minTop || bottom >= maxHeight))) {
renderable = false;
break;
}
width -= range.x;
left += range.x;
if (aspectRatio) {
height = width / aspectRatio;
top += range.Y / 2;
}
if (width < 0) {
dragType = 'e';
width = 0;
}
break;
case 's':
if (range.y >= 0 && (bottom >= maxHeight || aspectRatio && (left <= minLeft || right >= maxWidth))) {
renderable = false;
break;
}
height += range.y;
if (aspectRatio) {
width = height * aspectRatio;
left -= range.X / 2;
}
if (height < 0) {
dragType = 'n';
height = 0;
}
break;
case 'ne':
if (aspectRatio) {
if (range.y <= 0 && (top <= minTop || right >= maxWidth)) {
renderable = false;
break;
}
height -= range.y;
top += range.y;
width = height * aspectRatio;
} else {
if (range.x >= 0) {
if (right < maxWidth) {
width += range.x;
} else if (range.y <= 0 && top <= minTop) {
renderable = false;
}
} else {
width += range.x;
}
if (range.y <= 0) {
if (top > 0) {
height -= range.y;
top += range.y;
}
} else {
height -= range.y;
top += range.y;
}
}
if (width < 0 && height < 0) {
dragType = 'sw';
height = 0;
width = 0;
} else if (width < 0) {
dragType = 'nw';
width = 0;
} else if (height < 0) {
dragType = 'se';
height = 0;
}
break;
case 'nw':
if (aspectRatio) {
if (range.y <= 0 && (top <= minTop || left <= minLeft)) {
renderable = false;
break;
}
height -= range.y;
top += range.y;
width = height * aspectRatio;
left += range.X;
} else {
if (range.x <= 0) {
if (left > 0) {
width -= range.x;
left += range.x;
} else if (range.y <= 0 && top <= minTop) {
renderable = false;
}
} else {
width -= range.x;
left += range.x;
}
if (range.y <= 0) {
if (top > 0) {
height -= range.y;
top += range.y;
}
} else {
height -= range.y;
top += range.y;
}
}
if (width < 0 && height < 0) {
dragType = 'se';
height = 0;
width = 0;
} else if (width < 0) {
dragType = 'ne';
width = 0;
} else if (height < 0) {
dragType = 'sw';
height = 0;
}
break;
case 'sw':
if (aspectRatio) {
if (range.x <= 0 && (left <= minLeft || bottom >= maxHeight)) {
renderable = false;
break;
}
width -= range.x;
left += range.x;
height = width / aspectRatio;
} else {
if (range.x <= 0) {
if (left > 0) {
width -= range.x;
left += range.x;
} else if (range.y >= 0 && bottom >= maxHeight) {
renderable = false;
}
} else {
width -= range.x;
left += range.x;
}
if (range.y >= 0) {
if (bottom < maxHeight) {
height += range.y;
}
} else {
height += range.y;
}
}
if (width < 0 && height < 0) {
dragType = 'ne';
height = 0;
width = 0;
} else if (width < 0) {
dragType = 'se';
width = 0;
} else if (height < 0) {
dragType = 'nw';
height = 0;
}
break;
case 'se':
if (aspectRatio) {
if (range.x >= 0 && (right >= maxWidth || bottom >= maxHeight)) {
renderable = false;
break;
}
width += range.x;
height = width / aspectRatio;
} else {
if (range.x >= 0) {
if (right < maxWidth) {
width += range.x;
} else if (range.y >= 0 && bottom >= maxHeight) {
renderable = false;
}
} else {
width += range.x;
}
if (range.y >= 0) {
if (bottom < maxHeight) {
height += range.y;
}
} else {
height += range.y;
}
}
if (width < 0 && height < 0) {
dragType = 'nw';
height = 0;
width = 0;
} else if (width < 0) {
dragType = 'sw';
width = 0;
} else if (height < 0) {
dragType = 'ne';
height = 0;
}
break;
// Move image
case 'move':
canvas.left += range.x;
canvas.top += range.y;
this.renderCanvas(true);
renderable = false;
break;
// Scale image
case 'zoom':
this.zoom(function (x1, y1, x2, y2) {
var z1 = sqrt(x1 * x1 + y1 * y1),
z2 = sqrt(x2 * x2 + y2 * y2);
return (z2 - z1) / z1;
}(
abs(this.startX - this.startX2),
abs(this.startY - this.startY2),
abs(this.endX - this.endX2),
abs(this.endY - this.endY2)
));
this.startX2 = this.endX2;
this.startY2 = this.endY2;
renderable = false;
break;
// Crop image
case 'crop':
if (range.x && range.y) {
offset = this.$cropper.offset();
left = this.startX - offset.left;
top = this.startY - offset.top;
width = cropBox.minWidth;
height = cropBox.minHeight;
if (range.x > 0) {
if (range.y > 0) {
dragType = 'se';
} else {
dragType = 'ne';
top -= height;
}
} else {
if (range.y > 0) {
dragType = 'sw';
left -= width;
} else {
dragType = 'nw';
left -= width;
top -= height;
}
}
// Show the cropBox if is hidden
if (!this.cropped) {
this.cropped = true;
this.$cropBox.removeClass(CLASS_HIDDEN);
}
}
break;
// No default
}
if (renderable) {
cropBox.width = width;
cropBox.height = height;
cropBox.left = left;
cropBox.top = top;
this.dragType = dragType;
this.renderCropBox();
}
// Override
this.startX = this.endX;
this.startY = this.endY;
};
$.extend(Cropper.prototype, prototype);
Cropper.DEFAULTS = {
// Defines the aspect ratio of the crop box
// Type: Number
aspectRatio: NaN,
// Defines the percentage of automatic cropping area when initializes
// Type: Number (Must large than 0 and less than 1)
autoCropArea: 0.8, // 80%
// Outputs the cropping results.
// Type: Function
crop: null,
// Add extra containers for previewing
// Type: String (jQuery selector)
preview: '',
// Toggles
strict: true, // strict mode, the image cannot zoom out less than the container
responsive: true, // Rebuild when resize the window
checkImageOrigin: true, // Check if the target image is cross origin
modal: true, // Show the black modal
guides: true, // Show the dashed lines for guiding
highlight: true, // Show the white modal to highlight the crop box
background: true, // Show the grid background
autoCrop: true, // Enable to crop the image automatically when initialize
dragCrop: true, // Enable to create new crop box by dragging over the image
movable: true, // Enable to move the crop box
resizable: true, // Enable to resize the crop box
rotatable: true, // Enable to rotate the image
zoomable: true, // Enable to zoom the image
touchDragZoom: true, // Enable to zoom the image by wheeling mouse
mouseWheelZoom: true, // Enable to zoom the image by dragging touch
// Dimensions
minCanvasWidth: 0,
minCanvasHeight: 0,
minCropBoxWidth: 0,
minCropBoxHeight: 0,
minContainerWidth: 200,
minContainerHeight: 100,
// Events
build: null, // Function
built: null, // Function
dragstart: null, // Function
dragmove: null, // Function
dragend: null, // Function
zoomin: null, // Function
zoomout: null // Function
};
Cropper.setDefaults = function (options) {
$.extend(Cropper.DEFAULTS, options);
};
// Use the string compressor: Strmin (https://github.com/fengyuanchen/strmin)
Cropper.TEMPLATE = (function (source, words) {
words = words.split(',');
return source.replace(/\d+/g, function (i) {
return words[i];
});
})('<0 6="5-container"><0 6="5-canvas"></0><0 6="5-2-9" 3-2="move"></0><0 6="5-crop-9"><1 6="5-view-9"></1><1 6="5-8 8-h"></1><1 6="5-8 8-v"></1><1 6="5-face" 3-2="all"></1><1 6="5-7 7-e" 3-2="e"></1><1 6="5-7 7-n" 3-2="n"></1><1 6="5-7 7-w" 3-2="w"></1><1 6="5-7 7-s" 3-2="s"></1><1 6="5-4 4-e" 3-2="e"></1><1 6="5-4 4-n" 3-2="n"></1><1 6="5-4 4-w" 3-2="w"></1><1 6="5-4 4-s" 3-2="s"></1><1 6="5-4 4-ne" 3-2="ne"></1><1 6="5-4 4-nw" 3-2="nw"></1><1 6="5-4 4-sw" 3-2="sw"></1><1 6="5-4 4-se" 3-2="se"></1></0></0>', 'div,span,drag,data,point,cropper,class,line,dashed,box');
/* Template source:
<div class="cropper-container">
<div class="cropper-canvas"></div>
<div class="cropper-drag-box" data-drag="move"></div>
<div class="cropper-crop-box">
<span class="cropper-view-box"></span>
<span class="cropper-dashed dashed-h"></span>
<span class="cropper-dashed dashed-v"></span>
<span class="cropper-face" data-drag="all"></span>
<span class="cropper-line line-e" data-drag="e"></span>
<span class="cropper-line line-n" data-drag="n"></span>
<span class="cropper-line line-w" data-drag="w"></span>
<span class="cropper-line line-s" data-drag="s"></span>
<span class="cropper-point point-e" data-drag="e"></span>
<span class="cropper-point point-n" data-drag="n"></span>
<span class="cropper-point point-w" data-drag="w"></span>
<span class="cropper-point point-s" data-drag="s"></span>
<span class="cropper-point point-ne" data-drag="ne"></span>
<span class="cropper-point point-nw" data-drag="nw"></span>
<span class="cropper-point point-sw" data-drag="sw"></span>
<span class="cropper-point point-se" data-drag="se"></span>
</div>
</div>
*/
// Save the other cropper
Cropper.other = $.fn.cropper;
// Register as jQuery plugin
$.fn.cropper = function (options) {
var args = toArray(arguments, 1),
result;
this.each(function () {
var $this = $(this),
data = $this.data('cropper'),
fn;
if (!data) {
$this.data('cropper', (data = new Cropper(this, options)));
}
if (typeof options === 'string' && $.isFunction((fn = data[options]))) {
result = fn.apply(data, args);
}
});
return isUndefined(result) ? this : result;
};
$.fn.cropper.Constructor = Cropper;
$.fn.cropper.setDefaults = Cropper.setDefaults;
// No conflict
$.fn.cropper.noConflict = function () {
$.fn.cropper = Cropper.other;
return this;
};
function compress(img) { //图片压缩的方法
var initSize = img.src.length;
var width = img.width;
var height = img.height;
//如果图片大于四百万像素，计算压缩比并将大小压至400万以下
var ratio;
if ((ratio = width * height / 4000000)>1) {
ratio = Math.sqrt(ratio);
width /= ratio;
height /= ratio;
}else {
ratio = 1;
}
canvas.width = width;
canvas.height = height;
// 铺底色
ctx.fillStyle = "#fff";
ctx.fillRect(0, 0, canvas.width, canvas.height);
//如果图片像素大于100万则使用瓦片绘制
var count;
if ((count = width * height / 1000000) > 1) {
count = ~~(Math.sqrt(count)+1); //计算要分成多少块瓦片
// 计算每块瓦片的宽和高
var nw = ~~(width / count);
var nh = ~~(height / count);
tCanvas.width = nw;
tCanvas.height = nh;
for (var i = 0; i < count; i++) {
for (var j = 0; j < count; j++) {
tctx.drawImage(img, i * nw * ratio, j * nh * ratio, nw * ratio, nh * ratio, 0, 0, nw, nh);
ctx.drawImage(tCanvas, i * nw, j * nh, nw, nh);
}
}
} else {
ctx.drawImage(img, 0, 0, width, height);
}
//进行最小压缩
var ndata = canvas.toDataURL('image/jpeg', 0.1);
console.log('压缩前：' + initSize);
console.log('压缩后：' + ndata.length);
console.log('压缩率：' + ~~(100 * (initSize - ndata.length) / initSize) + "%");
tCanvas.width = tCanvas.height = canvas.width = canvas.height = 0;
return ndata;
}
});
这里的copper.js插件原来用的是 toDataUrl()方法 由于前面提到的问题我将它改成了compress方法
在做这个项目时我发现微信和QQ浏览器base64位数据前面要截取的文档头长度不一致
机会来临时无能为力才是最可悲的
