基于layui+cropper.js实现上传图片的裁剪功能的方法

前端的裁剪我知道的可以分为这么两种：flash一种，canvas一种。现在用的多的是canvas这种。

其实裁剪最本质的原理：通过工具获取到图片（不是JS那种获取DOM的方式，比如flash获取到图片，对图片任意操作，canvas也是一样，将图片放在画布上，任意操作）

本文使用的是canvas这种方式，借助的是cropper.js实现图片的裁剪。

由于前端页面使用的是layui这个框架，所有使用cropper时，最好的能够将cropper这个包作为一个layui的扩展嵌入到layui中，这样都省事，嵌入很简单，具体可以参考下面我封装好的代码

备注：cropper默认裁剪后的图片格式为png格式，如果需要自定义上传图片的格式，可以参考下面这段代码，如果不需要请直接忽略

cropper修改上传图片的格式：

var cas=imageEle.cropper('getCroppedCanvas');
var base64url=cas.toDataURL('image/jpeg');
console.log(base64url); //生成base64图片的格式

// 展示裁剪的图片的两种方式
// 方式一
$('.cavans').html(cas)  //在body显示出canvas元素

// 方式二
$('.canvans').attr("src", base64url);

封装好的cropper源码如下，包括cropper-jQuery的

具体代码：

cropper-css

/*!
 * Cropper.js v1.4.3
 * https://fengyuanchen.github.io/cropperjs
 *
 * Copyright 2015-present Chen Fengyuan
 * Released under the MIT license
 *
 * Date: 2018-10-24T13:07:11.429Z
 */

.cropper-container {
    direction: ltr;
    font-size: 0;
    line-height: 0;
    position: relative;
    -ms-touch-action: none;
    touch-action: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

.cropper-container img {
    display: block;
    height: 100%;
    image-orientation: 0deg;
    max-height: none !important;
    max-width: none !important;
    min-height: 0 !important;
    min-width: 0 !important;
    width: 100%;
}

.cropper-wrap-box,
.cropper-canvas,
.cropper-drag-box,
.cropper-crop-box,
.cropper-modal {
    bottom: 0;
    left: 0;
    position: absolute;
    right: 0;
    top: 0;
}

.cropper-wrap-box,
.cropper-canvas {
    overflow: hidden;
}

.cropper-drag-box {
    background-color: #fff;
    opacity: 0;
}

.cropper-modal {
    background-color: #000;
    opacity: .5;
}

.cropper-view-box {
    display: block;
    height: 100%;
    outline-color: rgba(51, 153, 255, 0.75);
    outline: 1px solid #39f;
    overflow: hidden;
    width: 100%;
}

.cropper-dashed {
    border: 0 dashed #eee;
    display: block;
    opacity: .5;
    position: absolute;
}

.cropper-dashed.dashed-h {
    border-bottom-width: 1px;
    border-top-width: 1px;
    height: calc(100% / 3);
    left: 0;
    top: calc(100% / 3);
    width: 100%;
}

.cropper-dashed.dashed-v {
    border-left-width: 1px;
    border-right-width: 1px;
    height: 100%;
    left: calc(100% / 3);
    top: 0;
    width: calc(100% / 3);
}

.cropper-center {
    display: block;
    height: 0;
    left: 50%;
    opacity: .75;
    position: absolute;
    top: 50%;
    width: 0;
}

.cropper-center:before,
.cropper-center:after {
    background-color: #eee;
    content: ' ';
    display: block;
    position: absolute;
}

.cropper-center:before {
    height: 1px;
    left: -3px;
    top: 0;
    width: 7px;
}

.cropper-center:after {
    height: 7px;
    left: 0;
    top: -3px;
    width: 1px;
}

.cropper-face,
.cropper-line,
.cropper-point {
    display: block;
    height: 100%;
    opacity: .1;
    position: absolute;
    width: 100%;
}

.cropper-face {
    background-color: #fff;
    left: 0;
    top: 0;
}

.cropper-line {
    background-color: #39f;
}

.cropper-line.line-e {
    cursor: ew-resize;
    right: -3px;
    top: 0;
    width: 5px;
}

.cropper-line.line-n {
    cursor: ns-resize;
    height: 5px;
    left: 0;
    top: -3px;
}

.cropper-line.line-w {
    cursor: ew-resize;
    left: -3px;
    top: 0;
    width: 5px;
}

.cropper-line.line-s {
    bottom: -3px;
    cursor: ns-resize;
    height: 5px;
    left: 0;
}

.cropper-point {
    background-color: #39f;
    height: 5px;
    opacity: .75;
    width: 5px;
}

.cropper-point.point-e {
    cursor: ew-resize;
    margin-top: -3px;
    right: -3px;
    top: 50%;
}

.cropper-point.point-n {
    cursor: ns-resize;
    left: 50%;
    margin-left: -3px;
    top: -3px;
}

.cropper-point.point-w {
    cursor: ew-resize;
    left: -3px;
    margin-top: -3px;
    top: 50%;
}

.cropper-point.point-s {
    bottom: -3px;
    cursor: s-resize;
    left: 50%;
    margin-left: -3px;
}

.cropper-point.point-ne {
    cursor: nesw-resize;
    right: -3px;
    top: -3px;
}

.cropper-point.point-nw {
    cursor: nwse-resize;
    left: -3px;
    top: -3px;
}

.cropper-point.point-sw {
    bottom: -3px;
    cursor: nesw-resize;
    left: -3px;
}

.cropper-point.point-se {
    bottom: -3px;
    cursor: nwse-resize;
    height: 20px;
    opacity: 1;
    right: -3px;
    width: 20px;
}

@media (min-width: 768px) {
    .cropper-point.point-se {
        height: 15px;
        width: 15px;
    }
}

@media (min-width: 992px) {
    .cropper-point.point-se {
        height: 10px;
        width: 10px;
    }
}

@media (min-width: 1200px) {
    .cropper-point.point-se {
        height: 5px;
        opacity: .75;
        width: 5px;
    }
}

.cropper-point.point-se:before {
    background-color: #39f;
    bottom: -50%;
    content: ' ';
    display: block;
    height: 200%;
    opacity: 0;
    position: absolute;
    right: -50%;
    width: 200%;
}

.cropper-invisible {
    opacity: 0;
}

.cropper-bg {
    background-image: url('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQAQMAAAAlPW0iAAAAA3NCSVQICAjb4U/gAAAABlBMVEXMzMz////TjRV2AAAACXBIWXMAAArrAAAK6wGCiw1aAAAAHHRFWHRTb2Z0d2FyZQBBZG9iZSBGaXJld29ya3MgQ1M26LyyjAAAABFJREFUCJlj+M/AgBVhF/0PAH6/D/HkDxOGAAAAAElFTkSuQmCC');
}

.cropper-hide {
    display: block;
    height: 0;
    position: absolute;
    width: 0;
}

.cropper-hidden {
    display: none !important;
}

.cropper-move {
    cursor: move;
}

.cropper-crop {
    cursor: crosshair;
}

.cropper-disabled .cropper-drag-box,
.cropper-disabled .cropper-face,
.cropper-disabled .cropper-line,
.cropper-disabled .cropper-point {
    cursor: not-allowed;
}

cropper-css

cropper-js

/*!
 * Cropper.js v1.4.3
 * https://fengyuanchen.github.io/cropperjs
 *
 * Copyright 2015-present Chen Fengyuan
 * Released under the MIT license
 *
 * Date: 2018-10-24T13:07:15.032Z
 */

(function (global, factory) {
    typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
        typeof define === 'function' && define.amd ? define(factory) :
            global.layui && layui.define ? layui.define(function (exports) {
                    exports('cropper', factory())
                }) :
                (global.Cropper = factory());
}(this, (function () {
    'use strict';

    function _typeof(obj) {
        if (typeof Symbol === "function" && typeof Symbol.iterator === "symbol") {
            _typeof = function (obj) {
                return typeof obj;
            };
        } else {
            _typeof = function (obj) {
                return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj;
            };
        }

        return _typeof(obj);
    }

    function _classCallCheck(instance, Constructor) {
        if (!(instance instanceof Constructor)) {
            throw new TypeError("Cannot call a class as a function");
        }
    }

    function _defineProperties(target, props) {
        for (var i = 0; i < props.length; i++) {
            var descriptor = props[i];
            descriptor.enumerable = descriptor.enumerable || false;
            descriptor.configurable = true;
            if ("value" in descriptor) descriptor.writable = true;
            Object.defineProperty(target, descriptor.key, descriptor);
        }
    }

    function _createClass(Constructor, protoProps, staticProps) {
        if (protoProps) _defineProperties(Constructor.prototype, protoProps);
        if (staticProps) _defineProperties(Constructor, staticProps);
        return Constructor;
    }

    function _toConsumableArray(arr) {
        return _arrayWithoutHoles(arr) || _iterableToArray(arr) || _nonIterableSpread();
    }

    function _arrayWithoutHoles(arr) {
        if (Array.isArray(arr)) {
            for (var i = 0, arr2 = new Array(arr.length); i < arr.length; i++) arr2[i] = arr[i];

            return arr2;
        }
    }

    function _iterableToArray(iter) {
        if (Symbol.iterator in Object(iter) || Object.prototype.toString.call(iter) === "[object Arguments]") return Array.from(iter);
    }

    function _nonIterableSpread() {
        throw new TypeError("Invalid attempt to spread non-iterable instance");
    }

    var IN_BROWSER = typeof window !== 'undefined';
    var WINDOW = IN_BROWSER ? window : {};
    var NAMESPACE = 'cropper'; // Actions

    var ACTION_ALL = 'all';
    var ACTION_CROP = 'crop';
    var ACTION_MOVE = 'move';
    var ACTION_ZOOM = 'zoom';
    var ACTION_EAST = 'e';
    var ACTION_WEST = 'w';
    var ACTION_SOUTH = 's';
    var ACTION_NORTH = 'n';
    var ACTION_NORTH_EAST = 'ne';
    var ACTION_NORTH_WEST = 'nw';
    var ACTION_SOUTH_EAST = 'se';
    var ACTION_SOUTH_WEST = 'sw'; // Classes

    var CLASS_CROP = "".concat(NAMESPACE, "-crop");
    var CLASS_DISABLED = "".concat(NAMESPACE, "-disabled");
    var CLASS_HIDDEN = "".concat(NAMESPACE, "-hidden");
    var CLASS_HIDE = "".concat(NAMESPACE, "-hide");
    var CLASS_INVISIBLE = "".concat(NAMESPACE, "-invisible");
    var CLASS_MODAL = "".concat(NAMESPACE, "-modal");
    var CLASS_MOVE = "".concat(NAMESPACE, "-move"); // Data keys

    var DATA_ACTION = "".concat(NAMESPACE, "Action");
    var DATA_PREVIEW = "".concat(NAMESPACE, "Preview"); // Drag modes

    var DRAG_MODE_CROP = 'crop';
    var DRAG_MODE_MOVE = 'move';
    var DRAG_MODE_NONE = 'none'; // Events

    var EVENT_CROP = 'crop';
    var EVENT_CROP_END = 'cropend';
    var EVENT_CROP_MOVE = 'cropmove';
    var EVENT_CROP_START = 'cropstart';
    var EVENT_DBLCLICK = 'dblclick';
    var EVENT_POINTER_DOWN = WINDOW.PointerEvent ? 'pointerdown' : 'touchstart mousedown';
    var EVENT_POINTER_MOVE = WINDOW.PointerEvent ? 'pointermove' : 'touchmove mousemove';
    var EVENT_POINTER_UP = WINDOW.PointerEvent ? 'pointerup pointercancel' : 'touchend touchcancel mouseup';
    var EVENT_READY = 'ready';
    var EVENT_RESIZE = 'resize';
    var EVENT_WHEEL = 'wheel mousewheel DOMMouseScroll';
    var EVENT_ZOOM = 'zoom'; // Mime types

    var MIME_TYPE_JPEG = 'image/jpeg'; // RegExps

    var REGEXP_ACTIONS = /^(?:e|w|s|n|se|sw|ne|nw|all|crop|move|zoom)$/;
    var REGEXP_DATA_URL = /^data:/;
    var REGEXP_DATA_URL_JPEG = /^data:image\/jpeg;base64,/;
    var REGEXP_TAG_NAME = /^(?:img|canvas)$/i;

    var DEFAULTS = {
        // Define the view mode of the cropper
        viewMode: 0,
        // 0, 1, 2, 3
        // Define the dragging mode of the cropper
        dragMode: DRAG_MODE_CROP,
        // 'crop', 'move' or 'none'
        // Define the initial aspect ratio of the crop box
        initialAspectRatio: NaN,
        // Define the aspect ratio of the crop box
        aspectRatio: NaN,
        // An object with the previous cropping result data
        data: null,
        // A selector for adding extra containers to preview
        preview: '',
        // Re-render the cropper when resize the window
        responsive: true,
        // Restore the cropped area after resize the window
        restore: true,
        // Check if the current image is a cross-origin image
        checkCrossOrigin: false,
        // Check the current image's Exif Orientation information
        checkOrientation: true,
        // Show the black modal
        modal: true,
        // Show the dashed lines for guiding
        guides: true,
        // Show the center indicator for guiding
        center: true,
        // Show the white modal to highlight the crop box
        highlight: true,
        // Show the grid background
        background: true,
        // Enable to crop the image automatically when initialize
        autoCrop: true,
        // Define the percentage of automatic cropping area when initializes
        autoCropArea: 0.8,
        // Enable to move the image
        movable: true,
        // Enable to rotate the image
        rotatable: true,
        // Enable to scale the image
        scalable: true,
        // Enable to zoom the image
        zoomable: true,
        // Enable to zoom the image by dragging touch
        zoomOnTouch: true,
        // Enable to zoom the image by wheeling mouse
        zoomOnWheel: true,
        // Define zoom ratio when zoom the image by wheeling mouse
        wheelZoomRatio: 0.1,
        // Enable to move the crop box
        cropBoxMovable: true,
        // Enable to resize the crop box
        cropBoxResizable: true,
        // Toggle drag mode between "crop" and "move" when click twice on the cropper
        toggleDragModeOnDblclick: true,
        // Size limitation
        minCanvasWidth: 0,
        minCanvasHeight: 0,
        minCropBoxWidth: 0,
        minCropBoxHeight: 0,
        minContainerWidth: 200,
        minContainerHeight: 100,
        // Shortcuts of events
        ready: null,
        cropstart: null,
        cropmove: null,
        cropend: null,
        crop: null,
        zoom: null
    };

    var TEMPLATE = '<div class="cropper-container" touch-action="none">' + '<div class="cropper-wrap-box">' + '<div class="cropper-canvas"></div>' + '</div>' + '<div class="cropper-drag-box"></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-center"></span>' + '<span class="cropper-face"></span>' + '<span class="cropper-line line-e" data-cropper-action="e"></span>' + '<span class="cropper-line line-n" data-cropper-action="n"></span>' + '<span class="cropper-line line-w" data-cropper-action="w"></span>' + '<span class="cropper-line line-s" data-cropper-action="s"></span>' + '<span class="cropper-point point-e" data-cropper-action="e"></span>' + '<span class="cropper-point point-n" data-cropper-action="n"></span>' + '<span class="cropper-point point-w" data-cropper-action="w"></span>' + '<span class="cropper-point point-s" data-cropper-action="s"></span>' + '<span class="cropper-point point-ne" data-cropper-action="ne"></span>' + '<span class="cropper-point point-nw" data-cropper-action="nw"></span>' + '<span class="cropper-point point-sw" data-cropper-action="sw"></span>' + '<span class="cropper-point point-se" data-cropper-action="se"></span>' + '</div>' + '</div>';

    /**
     * Check if the given value is not a number.
     */

    var isNaN = Number.isNaN || WINDOW.isNaN;

    /**
     * Check if the given value is a number.
     * @param {*} value - The value to check.
     * @returns {boolean} Returns `true` if the given value is a number, else `false`.
     */

    function isNumber(value) {
        return typeof value === 'number' && !isNaN(value);
    }

    /**
     * Check if the given value is undefined.
     * @param {*} value - The value to check.
     * @returns {boolean} Returns `true` if the given value is undefined, else `false`.
     */

    function isUndefined(value) {
        return typeof value === 'undefined';
    }

    /**
     * Check if the given value is an object.
     * @param {*} value - The value to check.
     * @returns {boolean} Returns `true` if the given value is an object, else `false`.
     */

    function isObject(value) {
        return _typeof(value) === 'object' && value !== null;
    }

    var hasOwnProperty = Object.prototype.hasOwnProperty;

    /**
     * Check if the given value is a plain object.
     * @param {*} value - The value to check.
     * @returns {boolean} Returns `true` if the given value is a plain object, else `false`.
     */

    function isPlainObject(value) {
        if (!isObject(value)) {
            return false;
        }

        try {
            var _constructor = value.constructor;
            var prototype = _constructor.prototype;
            return _constructor && prototype && hasOwnProperty.call(prototype, 'isPrototypeOf');
        } catch (e) {
            return false;
        }
    }

    /**
     * Check if the given value is a function.
     * @param {*} value - The value to check.
     * @returns {boolean} Returns `true` if the given value is a function, else `false`.
     */

    function isFunction(value) {
        return typeof value === 'function';
    }

    /**
     * Iterate the given data.
     * @param {*} data - The data to iterate.
     * @param {Function} callback - The process function for each element.
     * @returns {*} The original data.
     */

    function forEach(data, callback) {
        if (data && isFunction(callback)) {
            if (Array.isArray(data) || isNumber(data.length)
            /* array-like */
            ) {
                var length = data.length;
                var i;

                for (i = 0; i < length; i += 1) {
                    if (callback.call(data, data[i], i, data) === false) {
                        break;
                    }
                }
            } else if (isObject(data)) {
                Object.keys(data).forEach(function (key) {
                    callback.call(data, data[key], key, data);
                });
            }
        }

        return data;
    }

    /**
     * Extend the given object.
     * @param {*} obj - The object to be extended.
     * @param {*} args - The rest objects which will be merged to the first object.
     * @returns {Object} The extended object.
     */

    var assign = Object.assign || function assign(obj) {
        for (var _len = arguments.length, args = new Array(_len > 1 ? _len - 1 : 0), _key = 1; _key < _len; _key++) {
            args[_key - 1] = arguments[_key];
        }

        if (isObject(obj) && args.length > 0) {
            args.forEach(function (arg) {
                if (isObject(arg)) {
                    Object.keys(arg).forEach(function (key) {
                        obj[key] = arg[key];
                    });
                }
            });
        }

        return obj;
    };
    var REGEXP_DECIMALS = /\.\d*(?:0|9){12}\d*$/;

    /**
     * Normalize decimal number.
     * Check out {@link http://0.30000000000000004.com/}
     * @param {number} value - The value to normalize.
     * @param {number} [times=100000000000] - The times for normalizing.
     * @returns {number} Returns the normalized number.
     */

    function normalizeDecimalNumber(value) {
        var times = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 100000000000;
        return REGEXP_DECIMALS.test(value) ? Math.round(value * times) / times : value;
    }

    var REGEXP_SUFFIX = /^(?:width|height|left|top|marginLeft|marginTop)$/;

    /**
     * Apply styles to the given element.
     * @param {Element} element - The target element.
     * @param {Object} styles - The styles for applying.
     */

    function setStyle(element, styles) {
        var style = element.style;
        forEach(styles, function (value, property) {
            if (REGEXP_SUFFIX.test(property) && isNumber(value)) {
                value += 'px';
            }

            style[property] = value;
        });
    }

    /**
     * Check if the given element has a special class.
     * @param {Element} element - The element to check.
     * @param {string} value - The class to search.
     * @returns {boolean} Returns `true` if the special class was found.
     */

    function hasClass(element, value) {
        return element.classList ? element.classList.contains(value) : element.className.indexOf(value) > -1;
    }

    /**
     * Add classes to the given element.
     * @param {Element} element - The target element.
     * @param {string} value - The classes to be added.
     */

    function addClass(element, value) {
        if (!value) {
            return;
        }

        if (isNumber(element.length)) {
            forEach(element, function (elem) {
                addClass(elem, value);
            });
            return;
        }

        if (element.classList) {
            element.classList.add(value);
            return;
        }

        var className = element.className.trim();

        if (!className) {
            element.className = value;
        } else if (className.indexOf(value) < 0) {
            element.className = "".concat(className, " ").concat(value);
        }
    }

    /**
     * Remove classes from the given element.
     * @param {Element} element - The target element.
     * @param {string} value - The classes to be removed.
     */

    function removeClass(element, value) {
        if (!value) {
            return;
        }

        if (isNumber(element.length)) {
            forEach(element, function (elem) {
                removeClass(elem, value);
            });
            return;
        }

        if (element.classList) {
            element.classList.remove(value);
            return;
        }

        if (element.className.indexOf(value) >= 0) {
            element.className = element.className.replace(value, '');
        }
    }

    /**
     * Add or remove classes from the given element.
     * @param {Element} element - The target element.
     * @param {string} value - The classes to be toggled.
     * @param {boolean} added - Add only.
     */

    function toggleClass(element, value, added) {
        if (!value) {
            return;
        }

        if (isNumber(element.length)) {
            forEach(element, function (elem) {
                toggleClass(elem, value, added);
            });
            return;
        } // IE10-11 doesn't support the second parameter of `classList.toggle`


        if (added) {
            addClass(element, value);
        } else {
            removeClass(element, value);
        }
    }

    var REGEXP_HYPHENATE = /([a-z\d])([A-Z])/g;

    /**
     * Transform the given string from camelCase to kebab-case
     * @param {string} value - The value to transform.
     * @returns {string} The transformed value.
     */

    function hyphenate(value) {
        return value.replace(REGEXP_HYPHENATE, '$1-$2').toLowerCase();
    }

    /**
     * Get data from the given element.
     * @param {Element} element - The target element.
     * @param {string} name - The data key to get.
     * @returns {string} The data value.
     */

    function getData(element, name) {
        if (isObject(element[name])) {
            return element[name];
        }

        if (element.dataset) {
            return element.dataset[name];
        }

        return element.getAttribute("data-".concat(hyphenate(name)));
    }

    /**
     * Set data to the given element.
     * @param {Element} element - The target element.
     * @param {string} name - The data key to set.
     * @param {string} data - The data value.
     */

    function setData(element, name, data) {
        if (isObject(data)) {
            element[name] = data;
        } else if (element.dataset) {
            element.dataset[name] = data;
        } else {
            element.setAttribute("data-".concat(hyphenate(name)), data);
        }
    }

    /**
     * Remove data from the given element.
     * @param {Element} element - The target element.
     * @param {string} name - The data key to remove.
     */

    function removeData(element, name) {
        if (isObject(element[name])) {
            try {
                delete element[name];
            } catch (e) {
                element[name] = undefined;
            }
        } else if (element.dataset) {
            // #128 Safari not allows to delete dataset property
            try {
                delete element.dataset[name];
            } catch (e) {
                element.dataset[name] = undefined;
            }
        } else {
            element.removeAttribute("data-".concat(hyphenate(name)));
        }
    }

    var REGEXP_SPACES = /\s\s*/;

    var onceSupported = function () {
        var supported = false;

        if (IN_BROWSER) {
            var once = false;

            var listener = function listener() {
            };

            var options = Object.defineProperty({}, 'once', {
                get: function get() {
                    supported = true;
                    return once;
                },

                /**
                 * This setter can fix a `TypeError` in strict mode
                 * {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/Getter_only}
                 * @param {boolean} value - The value to set
                 */
                set: function set(value) {
                    once = value;
                }
            });
            WINDOW.addEventListener('test', listener, options);
            WINDOW.removeEventListener('test', listener, options);
        }

        return supported;
    }();

    /**
     * Remove event listener from the target element.
     * @param {Element} element - The event target.
     * @param {string} type - The event type(s).
     * @param {Function} listener - The event listener.
     * @param {Object} options - The event options.
     */


    function removeListener(element, type, listener) {
        var options = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : {};
        var handler = listener;
        type.trim().split(REGEXP_SPACES).forEach(function (event) {
            if (!onceSupported) {
                var listeners = element.listeners;

                if (listeners && listeners[event] && listeners[event][listener]) {
                    handler = listeners[event][listener];
                    delete listeners[event][listener];

                    if (Object.keys(listeners[event]).length === 0) {
                        delete listeners[event];
                    }

                    if (Object.keys(listeners).length === 0) {
                        delete element.listeners;
                    }
                }
            }

            element.removeEventListener(event, handler, options);
        });
    }

    /**
     * Add event listener to the target element.
     * @param {Element} element - The event target.
     * @param {string} type - The event type(s).
     * @param {Function} listener - The event listener.
     * @param {Object} options - The event options.
     */

    function addListener(element, type, listener) {
        var options = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : {};
        var _handler = listener;
        type.trim().split(REGEXP_SPACES).forEach(function (event) {
            if (options.once && !onceSupported) {
                var _element$listeners = element.listeners,
                    listeners = _element$listeners === void 0 ? {} : _element$listeners;

                _handler = function handler() {
                    delete listeners[event][listener];
                    element.removeEventListener(event, _handler, options);

                    for (var _len2 = arguments.length, args = new Array(_len2), _key2 = 0; _key2 < _len2; _key2++) {
                        args[_key2] = arguments[_key2];
                    }

                    listener.apply(element, args);
                };

                if (!listeners[event]) {
                    listeners[event] = {};
                }

                if (listeners[event][listener]) {
                    element.removeEventListener(event, listeners[event][listener], options);
                }

                listeners[event][listener] = _handler;
                element.listeners = listeners;
            }

            element.addEventListener(event, _handler, options);
        });
    }

    /**
     * Dispatch event on the target element.
     * @param {Element} element - The event target.
     * @param {string} type - The event type(s).
     * @param {Object} data - The additional event data.
     * @returns {boolean} Indicate if the event is default prevented or not.
     */

    function dispatchEvent(element, type, data) {
        var event; // Event and CustomEvent on IE9-11 are global objects, not constructors

        if (isFunction(Event) && isFunction(CustomEvent)) {
            event = new CustomEvent(type, {
                detail: data,
                bubbles: true,
                cancelable: true
            });
        } else {
            event = document.createEvent('CustomEvent');
            event.initCustomEvent(type, true, true, data);
        }

        return element.dispatchEvent(event);
    }

    /**
     * Get the offset base on the document.
     * @param {Element} element - The target element.
     * @returns {Object} The offset data.
     */

    function getOffset(element) {
        var box = element.getBoundingClientRect();
        return {
            left: box.left + (window.pageXOffset - document.documentElement.clientLeft),
            top: box.top + (window.pageYOffset - document.documentElement.clientTop)
        };
    }

    var location = WINDOW.location;
    var REGEXP_ORIGINS = /^(https?:)\/\/([^:/?#]+):?(\d*)/i;

    /**
     * Check if the given URL is a cross origin URL.
     * @param {string} url - The target URL.
     * @returns {boolean} Returns `true` if the given URL is a cross origin URL, else `false`.
     */

    function isCrossOriginURL(url) {
        var parts = url.match(REGEXP_ORIGINS);
        return parts && (parts[1] !== location.protocol || parts[2] !== location.hostname || parts[3] !== location.port);
    }

    /**
     * Add timestamp to the given URL.
     * @param {string} url - The target URL.
     * @returns {string} The result URL.
     */

    function addTimestamp(url) {
        var timestamp = "timestamp=".concat(new Date().getTime());
        return url + (url.indexOf('?') === -1 ? '?' : '&') + timestamp;
    }

    /**
     * Get transforms base on the given object.
     * @param {Object} obj - The target object.
     * @returns {string} A string contains transform values.
     */

    function getTransforms(_ref) {
        var rotate = _ref.rotate,
            scaleX = _ref.scaleX,
            scaleY = _ref.scaleY,
            translateX = _ref.translateX,
            translateY = _ref.translateY;
        var values = [];

        if (isNumber(translateX) && translateX !== 0) {
            values.push("translateX(".concat(translateX, "px)"));
        }

        if (isNumber(translateY) && translateY !== 0) {
            values.push("translateY(".concat(translateY, "px)"));
        } // Rotate should come first before scale to match orientation transform


        if (isNumber(rotate) && rotate !== 0) {
            values.push("rotate(".concat(rotate, "deg)"));
        }

        if (isNumber(scaleX) && scaleX !== 1) {
            values.push("scaleX(".concat(scaleX, ")"));
        }

        if (isNumber(scaleY) && scaleY !== 1) {
            values.push("scaleY(".concat(scaleY, ")"));
        }

        var transform = values.length ? values.join(' ') : 'none';
        return {
            WebkitTransform: transform,
            msTransform: transform,
            transform: transform
        };
    }

    /**
     * Get the max ratio of a group of pointers.
     * @param {string} pointers - The target pointers.
     * @returns {number} The result ratio.
     */

    function getMaxZoomRatio(pointers) {
        var pointers2 = assign({}, pointers);
        var ratios = [];
        forEach(pointers, function (pointer, pointerId) {
            delete pointers2[pointerId];
            forEach(pointers2, function (pointer2) {
                var x1 = Math.abs(pointer.startX - pointer2.startX);
                var y1 = Math.abs(pointer.startY - pointer2.startY);
                var x2 = Math.abs(pointer.endX - pointer2.endX);
                var y2 = Math.abs(pointer.endY - pointer2.endY);
                var z1 = Math.sqrt(x1 * x1 + y1 * y1);
                var z2 = Math.sqrt(x2 * x2 + y2 * y2);
                var ratio = (z2 - z1) / z1;
                ratios.push(ratio);
            });
        });
        ratios.sort(function (a, b) {
            return Math.abs(a) < Math.abs(b);
        });
        return ratios[0];
    }

    /**
     * Get a pointer from an event object.
     * @param {Object} event - The target event object.
     * @param {boolean} endOnly - Indicates if only returns the end point coordinate or not.
     * @returns {Object} The result pointer contains start and/or end point coordinates.
     */

    function getPointer(_ref2, endOnly) {
        var pageX = _ref2.pageX,
            pageY = _ref2.pageY;
        var end = {
            endX: pageX,
            endY: pageY
        };
        return endOnly ? end : assign({
            startX: pageX,
            startY: pageY
        }, end);
    }

    /**
     * Get the center point coordinate of a group of pointers.
     * @param {Object} pointers - The target pointers.
     * @returns {Object} The center point coordinate.
     */

    function getPointersCenter(pointers) {
        var pageX = 0;
        var pageY = 0;
        var count = 0;
        forEach(pointers, function (_ref3) {
            var startX = _ref3.startX,
                startY = _ref3.startY;
            pageX += startX;
            pageY += startY;
            count += 1;
        });
        pageX /= count;
        pageY /= count;
        return {
            pageX: pageX,
            pageY: pageY
        };
    }

    /**
     * Check if the given value is a finite number.
     */

    var isFinite = Number.isFinite || WINDOW.isFinite;

    /**
     * Get the max sizes in a rectangle under the given aspect ratio.
     * @param {Object} data - The original sizes.
     * @param {string} [type='contain'] - The adjust type.
     * @returns {Object} The result sizes.
     */

    function getAdjustedSizes(_ref4) // or 'cover'
    {
        var aspectRatio = _ref4.aspectRatio,
            height = _ref4.height,
            width = _ref4.width;
        var type = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 'contain';

        var isValidNumber = function isValidNumber(value) {
            return isFinite(value) && value > 0;
        };

        if (isValidNumber(width) && isValidNumber(height)) {
            var adjustedWidth = height * aspectRatio;

            if (type === 'contain' && adjustedWidth > width || type === 'cover' && adjustedWidth < width) {
                height = width / aspectRatio;
            } else {
                width = height * aspectRatio;
            }
        } else if (isValidNumber(width)) {
            height = width / aspectRatio;
        } else if (isValidNumber(height)) {
            width = height * aspectRatio;
        }

        return {
            width: width,
            height: height
        };
    }

    /**
     * Get the new sizes of a rectangle after rotated.
     * @param {Object} data - The original sizes.
     * @returns {Object} The result sizes.
     */

    function getRotatedSizes(_ref5) {
        var width = _ref5.width,
            height = _ref5.height,
            degree = _ref5.degree;
        degree = Math.abs(degree) % 180;

        if (degree === 90) {
            return {
                width: height,
                height: width
            };
        }

        var arc = degree % 90 * Math.PI / 180;
        var sinArc = Math.sin(arc);
        var cosArc = Math.cos(arc);
        var newWidth = width * cosArc + height * sinArc;
        var newHeight = width * sinArc + height * cosArc;
        return degree > 90 ? {
            width: newHeight,
            height: newWidth
        } : {
            width: newWidth,
            height: newHeight
        };
    }

    /**
     * Get a canvas which drew the given image.
     * @param {HTMLImageElement} image - The image for drawing.
     * @param {Object} imageData - The image data.
     * @param {Object} canvasData - The canvas data.
     * @param {Object} options - The options.
     * @returns {HTMLCanvasElement} The result canvas.
     */

    function getSourceCanvas(image, _ref6, _ref7, _ref8) {
        var imageAspectRatio = _ref6.aspectRatio,
            imageNaturalWidth = _ref6.naturalWidth,
            imageNaturalHeight = _ref6.naturalHeight,
            _ref6$rotate = _ref6.rotate,
            rotate = _ref6$rotate === void 0 ? 0 : _ref6$rotate,
            _ref6$scaleX = _ref6.scaleX,
            scaleX = _ref6$scaleX === void 0 ? 1 : _ref6$scaleX,
            _ref6$scaleY = _ref6.scaleY,
            scaleY = _ref6$scaleY === void 0 ? 1 : _ref6$scaleY;
        var aspectRatio = _ref7.aspectRatio,
            naturalWidth = _ref7.naturalWidth,
            naturalHeight = _ref7.naturalHeight;
        var _ref8$fillColor = _ref8.fillColor,
            fillColor = _ref8$fillColor === void 0 ? 'transparent' : _ref8$fillColor,
            _ref8$imageSmoothingE = _ref8.imageSmoothingEnabled,
            imageSmoothingEnabled = _ref8$imageSmoothingE === void 0 ? true : _ref8$imageSmoothingE,
            _ref8$imageSmoothingQ = _ref8.imageSmoothingQuality,
            imageSmoothingQuality = _ref8$imageSmoothingQ === void 0 ? 'low' : _ref8$imageSmoothingQ,
            _ref8$maxWidth = _ref8.maxWidth,
            maxWidth = _ref8$maxWidth === void 0 ? Infinity : _ref8$maxWidth,
            _ref8$maxHeight = _ref8.maxHeight,
            maxHeight = _ref8$maxHeight === void 0 ? Infinity : _ref8$maxHeight,
            _ref8$minWidth = _ref8.minWidth,
            minWidth = _ref8$minWidth === void 0 ? 0 : _ref8$minWidth,
            _ref8$minHeight = _ref8.minHeight,
            minHeight = _ref8$minHeight === void 0 ? 0 : _ref8$minHeight;
        var canvas = document.createElement('canvas');
        var context = canvas.getContext('2d');
        var maxSizes = getAdjustedSizes({
            aspectRatio: aspectRatio,
            width: maxWidth,
            height: maxHeight
        });
        var minSizes = getAdjustedSizes({
            aspectRatio: aspectRatio,
            width: minWidth,
            height: minHeight
        }, 'cover');
        var width = Math.min(maxSizes.width, Math.max(minSizes.width, naturalWidth));
        var height = Math.min(maxSizes.height, Math.max(minSizes.height, naturalHeight)); // Note: should always use image's natural sizes for drawing as
        // imageData.naturalWidth === canvasData.naturalHeight when rotate % 180 === 90

        var destMaxSizes = getAdjustedSizes({
            aspectRatio: imageAspectRatio,
            width: maxWidth,
            height: maxHeight
        });
        var destMinSizes = getAdjustedSizes({
            aspectRatio: imageAspectRatio,
            width: minWidth,
            height: minHeight
        }, 'cover');
        var destWidth = Math.min(destMaxSizes.width, Math.max(destMinSizes.width, imageNaturalWidth));
        var destHeight = Math.min(destMaxSizes.height, Math.max(destMinSizes.height, imageNaturalHeight));
        var params = [-destWidth / 2, -destHeight / 2, destWidth, destHeight];
        canvas.width = normalizeDecimalNumber(width);
        canvas.height = normalizeDecimalNumber(height);
        context.fillStyle = fillColor;
        context.fillRect(0, 0, width, height);
        context.save();
        context.translate(width / 2, height / 2);
        context.rotate(rotate * Math.PI / 180);
        context.scale(scaleX, scaleY);
        context.imageSmoothingEnabled = imageSmoothingEnabled;
        context.imageSmoothingQuality = imageSmoothingQuality;
        context.drawImage.apply(context, [image].concat(_toConsumableArray(params.map(function (param) {
            return Math.floor(normalizeDecimalNumber(param));
        }))));
        context.restore();
        return canvas;
    }

    var fromCharCode = String.fromCharCode;

    /**
     * Get string from char code in data view.
     * @param {DataView} dataView - The data view for read.
     * @param {number} start - The start index.
     * @param {number} length - The read length.
     * @returns {string} The read result.
     */

    function getStringFromCharCode(dataView, start, length) {
        var str = '';
        var i;
        length += start;

        for (i = start; i < length; i += 1) {
            str += fromCharCode(dataView.getUint8(i));
        }

        return str;
    }

    var REGEXP_DATA_URL_HEAD = /^data:.*,/;

    /**
     * Transform Data URL to array buffer.
     * @param {string} dataURL - The Data URL to transform.
     * @returns {ArrayBuffer} The result array buffer.
     */

    function dataURLToArrayBuffer(dataURL) {
        var base64 = dataURL.replace(REGEXP_DATA_URL_HEAD, '');
        var binary = atob(base64);
        var arrayBuffer = new ArrayBuffer(binary.length);
        var uint8 = new Uint8Array(arrayBuffer);
        forEach(uint8, function (value, i) {
            uint8[i] = binary.charCodeAt(i);
        });
        return arrayBuffer;
    }

    /**
     * Transform array buffer to Data URL.
     * @param {ArrayBuffer} arrayBuffer - The array buffer to transform.
     * @param {string} mimeType - The mime type of the Data URL.
     * @returns {string} The result Data URL.
     */

    function arrayBufferToDataURL(arrayBuffer, mimeType) {
        var chunks = [];
        var chunkSize = 8192;
        var uint8 = new Uint8Array(arrayBuffer);

        while (uint8.length > 0) {
            chunks.push(fromCharCode.apply(void 0, _toConsumableArray(uint8.subarray(0, chunkSize))));
            uint8 = uint8.subarray(chunkSize);
        }

        return "data:".concat(mimeType, ";base64,").concat(btoa(chunks.join('')));
    }

    /**
     * Get orientation value from given array buffer.
     * @param {ArrayBuffer} arrayBuffer - The array buffer to read.
     * @returns {number} The read orientation value.
     */

    function resetAndGetOrientation(arrayBuffer) {
        var dataView = new DataView(arrayBuffer);
        var orientation; // Ignores range error when the image does not have correct Exif information

        try {
            var littleEndian;
            var app1Start;
            var ifdStart; // Only handle JPEG image (start by 0xFFD8)

            if (dataView.getUint8(0) === 0xFF && dataView.getUint8(1) === 0xD8) {
                var length = dataView.byteLength;
                var offset = 2;

                while (offset + 1 < length) {
                    if (dataView.getUint8(offset) === 0xFF && dataView.getUint8(offset + 1) === 0xE1) {
                        app1Start = offset;
                        break;
                    }

                    offset += 1;
                }
            }

            if (app1Start) {
                var exifIDCode = app1Start + 4;
                var tiffOffset = app1Start + 10;

                if (getStringFromCharCode(dataView, exifIDCode, 4) === 'Exif') {
                    var endianness = dataView.getUint16(tiffOffset);
                    littleEndian = endianness === 0x4949;

                    if (littleEndian || endianness === 0x4D4D
                    /* bigEndian */
                    ) {
                        if (dataView.getUint16(tiffOffset + 2, littleEndian) === 0x002A) {
                            var firstIFDOffset = dataView.getUint32(tiffOffset + 4, littleEndian);

                            if (firstIFDOffset >= 0x00000008) {
                                ifdStart = tiffOffset + firstIFDOffset;
                            }
                        }
                    }
                }
            }

            if (ifdStart) {
                var _length = dataView.getUint16(ifdStart, littleEndian);

                var _offset;

                var i;

                for (i = 0; i < _length; i += 1) {
                    _offset = ifdStart + i * 12 + 2;

                    if (dataView.getUint16(_offset, littleEndian) === 0x0112
                    /* Orientation */
                    ) {
                        // 8 is the offset of the current tag's value
                        _offset += 8; // Get the original orientation value

                        orientation = dataView.getUint16(_offset, littleEndian); // Override the orientation with its default value

                        dataView.setUint16(_offset, 1, littleEndian);
                        break;
                    }
                }
            }
        } catch (e) {
            orientation = 1;
        }

        return orientation;
    }

    /**
     * Parse Exif Orientation value.
     * @param {number} orientation - The orientation to parse.
     * @returns {Object} The parsed result.
     */

    function parseOrientation(orientation) {
        var rotate = 0;
        var scaleX = 1;
        var scaleY = 1;

        switch (orientation) {
            // Flip horizontal
            case 2:
                scaleX = -1;
                break;
            // Rotate left 180°

            case 3:
                rotate = -180;
                break;
            // Flip vertical

            case 4:
                scaleY = -1;
                break;
            // Flip vertical and rotate right 90°

            case 5:
                rotate = 90;
                scaleY = -1;
                break;
            // Rotate right 90°

            case 6:
                rotate = 90;
                break;
            // Flip horizontal and rotate right 90°

            case 7:
                rotate = 90;
                scaleX = -1;
                break;
            // Rotate left 90°

            case 8:
                rotate = -90;
                break;

            default:
        }

        return {
            rotate: rotate,
            scaleX: scaleX,
            scaleY: scaleY
        };
    }

    var render = {
        render: function render() {
            this.initContainer();
            this.initCanvas();
            this.initCropBox();
            this.renderCanvas();

            if (this.cropped) {
                this.renderCropBox();
            }
        },
        initContainer: function initContainer() {
            var element = this.element,
                options = this.options,
                container = this.container,
                cropper = this.cropper;
            addClass(cropper, CLASS_HIDDEN);
            removeClass(element, CLASS_HIDDEN);
            var containerData = {
                width: Math.max(container.offsetWidth, Number(options.minContainerWidth) || 200),
                height: Math.max(container.offsetHeight, Number(options.minContainerHeight) || 100)
            };
            this.containerData = containerData;
            setStyle(cropper, {
                width: containerData.width,
                height: containerData.height
            });
            addClass(element, CLASS_HIDDEN);
            removeClass(cropper, CLASS_HIDDEN);
        },
        // Canvas (image wrapper)
        initCanvas: function initCanvas() {
            var containerData = this.containerData,
                imageData = this.imageData;
            var viewMode = this.options.viewMode;
            var rotated = Math.abs(imageData.rotate) % 180 === 90;
            var naturalWidth = rotated ? imageData.naturalHeight : imageData.naturalWidth;
            var naturalHeight = rotated ? imageData.naturalWidth : imageData.naturalHeight;
            var aspectRatio = naturalWidth / naturalHeight;
            var canvasWidth = containerData.width;
            var canvasHeight = containerData.height;

            if (containerData.height * aspectRatio > containerData.width) {
                if (viewMode === 3) {
                    canvasWidth = containerData.height * aspectRatio;
                } else {
                    canvasHeight = containerData.width / aspectRatio;
                }
            } else if (viewMode === 3) {
                canvasHeight = containerData.width / aspectRatio;
            } else {
                canvasWidth = containerData.height * aspectRatio;
            }

            var canvasData = {
                aspectRatio: aspectRatio,
                naturalWidth: naturalWidth,
                naturalHeight: naturalHeight,
                width: canvasWidth,
                height: canvasHeight
            };
            canvasData.left = (containerData.width - canvasWidth) / 2;
            canvasData.top = (containerData.height - canvasHeight) / 2;
            canvasData.oldLeft = canvasData.left;
            canvasData.oldTop = canvasData.top;
            this.canvasData = canvasData;
            this.limited = viewMode === 1 || viewMode === 2;
            this.limitCanvas(true, true);
            this.initialImageData = assign({}, imageData);
            this.initialCanvasData = assign({}, canvasData);
        },
        limitCanvas: function limitCanvas(sizeLimited, positionLimited) {
            var options = this.options,
                containerData = this.containerData,
                canvasData = this.canvasData,
                cropBoxData = this.cropBoxData;
            var viewMode = options.viewMode;
            var aspectRatio = canvasData.aspectRatio;
            var cropped = this.cropped && cropBoxData;

            if (sizeLimited) {
                var minCanvasWidth = Number(options.minCanvasWidth) || 0;
                var minCanvasHeight = Number(options.minCanvasHeight) || 0;

                if (viewMode > 1) {
                    minCanvasWidth = Math.max(minCanvasWidth, containerData.width);
                    minCanvasHeight = Math.max(minCanvasHeight, containerData.height);

                    if (viewMode === 3) {
                        if (minCanvasHeight * aspectRatio > minCanvasWidth) {
                            minCanvasWidth = minCanvasHeight * aspectRatio;
                        } else {
                            minCanvasHeight = minCanvasWidth / aspectRatio;
                        }
                    }
                } else if (viewMode > 0) {
                    if (minCanvasWidth) {
                        minCanvasWidth = Math.max(minCanvasWidth, cropped ? cropBoxData.width : 0);
                    } else if (minCanvasHeight) {
                        minCanvasHeight = Math.max(minCanvasHeight, cropped ? cropBoxData.height : 0);
                    } else if (cropped) {
                        minCanvasWidth = cropBoxData.width;
                        minCanvasHeight = cropBoxData.height;

                        if (minCanvasHeight * aspectRatio > minCanvasWidth) {
                            minCanvasWidth = minCanvasHeight * aspectRatio;
                        } else {
                            minCanvasHeight = minCanvasWidth / aspectRatio;
                        }
                    }
                }

                var _getAdjustedSizes = getAdjustedSizes({
                    aspectRatio: aspectRatio,
                    width: minCanvasWidth,
                    height: minCanvasHeight
                });

                minCanvasWidth = _getAdjustedSizes.width;
                minCanvasHeight = _getAdjustedSizes.height;
                canvasData.minWidth = minCanvasWidth;
                canvasData.minHeight = minCanvasHeight;
                canvasData.maxWidth = Infinity;
                canvasData.maxHeight = Infinity;
            }

            if (positionLimited) {
                if (viewMode > (cropped ? 0 : 1)) {
                    var newCanvasLeft = containerData.width - canvasData.width;
                    var newCanvasTop = containerData.height - canvasData.height;
                    canvasData.minLeft = Math.min(0, newCanvasLeft);
                    canvasData.minTop = Math.min(0, newCanvasTop);
                    canvasData.maxLeft = Math.max(0, newCanvasLeft);
                    canvasData.maxTop = Math.max(0, newCanvasTop);

                    if (cropped && this.limited) {
                        canvasData.minLeft = Math.min(cropBoxData.left, cropBoxData.left + (cropBoxData.width - canvasData.width));
                        canvasData.minTop = Math.min(cropBoxData.top, cropBoxData.top + (cropBoxData.height - canvasData.height));
                        canvasData.maxLeft = cropBoxData.left;
                        canvasData.maxTop = cropBoxData.top;

                        if (viewMode === 2) {
                            if (canvasData.width >= containerData.width) {
                                canvasData.minLeft = Math.min(0, newCanvasLeft);
                                canvasData.maxLeft = Math.max(0, newCanvasLeft);
                            }

                            if (canvasData.height >= containerData.height) {
                                canvasData.minTop = Math.min(0, newCanvasTop);
                                canvasData.maxTop = Math.max(0, newCanvasTop);
                            }
                        }
                    }
                } else {
                    canvasData.minLeft = -canvasData.width;
                    canvasData.minTop = -canvasData.height;
                    canvasData.maxLeft = containerData.width;
                    canvasData.maxTop = containerData.height;
                }
            }
        },
        renderCanvas: function renderCanvas(changed, transformed) {
            var canvasData = this.canvasData,
                imageData = this.imageData;

            if (transformed) {
                var _getRotatedSizes = getRotatedSizes({
                        width: imageData.naturalWidth * Math.abs(imageData.scaleX || 1),
                        height: imageData.naturalHeight * Math.abs(imageData.scaleY || 1),
                        degree: imageData.rotate || 0
                    }),
                    naturalWidth = _getRotatedSizes.width,
                    naturalHeight = _getRotatedSizes.height;

                var width = canvasData.width * (naturalWidth / canvasData.naturalWidth);
                var height = canvasData.height * (naturalHeight / canvasData.naturalHeight);
                canvasData.left -= (width - canvasData.width) / 2;
                canvasData.top -= (height - canvasData.height) / 2;
                canvasData.width = width;
                canvasData.height = height;
                canvasData.aspectRatio = naturalWidth / naturalHeight;
                canvasData.naturalWidth = naturalWidth;
                canvasData.naturalHeight = naturalHeight;
                this.limitCanvas(true, false);
            }

            if (canvasData.width > canvasData.maxWidth || canvasData.width < canvasData.minWidth) {
                canvasData.left = canvasData.oldLeft;
            }

            if (canvasData.height > canvasData.maxHeight || canvasData.height < canvasData.minHeight) {
                canvasData.top = canvasData.oldTop;
            }

            canvasData.width = Math.min(Math.max(canvasData.width, canvasData.minWidth), canvasData.maxWidth);
            canvasData.height = Math.min(Math.max(canvasData.height, canvasData.minHeight), canvasData.maxHeight);
            this.limitCanvas(false, true);
            canvasData.left = Math.min(Math.max(canvasData.left, canvasData.minLeft), canvasData.maxLeft);
            canvasData.top = Math.min(Math.max(canvasData.top, canvasData.minTop), canvasData.maxTop);
            canvasData.oldLeft = canvasData.left;
            canvasData.oldTop = canvasData.top;
            setStyle(this.canvas, assign({
                width: canvasData.width,
                height: canvasData.height
            }, getTransforms({
                translateX: canvasData.left,
                translateY: canvasData.top
            })));
            this.renderImage(changed);

            if (this.cropped && this.limited) {
                this.limitCropBox(true, true);
            }
        },
        renderImage: function renderImage(changed) {
            var canvasData = this.canvasData,
                imageData = this.imageData;
            var width = imageData.naturalWidth * (canvasData.width / canvasData.naturalWidth);
            var height = imageData.naturalHeight * (canvasData.height / canvasData.naturalHeight);
            assign(imageData, {
                width: width,
                height: height,
                left: (canvasData.width - width) / 2,
                top: (canvasData.height - height) / 2
            });
            setStyle(this.image, assign({
                width: imageData.width,
                height: imageData.height
            }, getTransforms(assign({
                translateX: imageData.left,
                translateY: imageData.top
            }, imageData))));

            if (changed) {
                this.output();
            }
        },
        initCropBox: function initCropBox() {
            var options = this.options,
                canvasData = this.canvasData;
            var aspectRatio = options.aspectRatio || options.initialAspectRatio;
            var autoCropArea = Number(options.autoCropArea) || 0.8;
            var cropBoxData = {
                width: canvasData.width,
                height: canvasData.height
            };

            if (aspectRatio) {
                if (canvasData.height * aspectRatio > canvasData.width) {
                    cropBoxData.height = cropBoxData.width / aspectRatio;
                } else {
                    cropBoxData.width = cropBoxData.height * aspectRatio;
                }
            }

            this.cropBoxData = cropBoxData;
            this.limitCropBox(true, true); // Initialize auto crop area

            cropBoxData.width = Math.min(Math.max(cropBoxData.width, cropBoxData.minWidth), cropBoxData.maxWidth);
            cropBoxData.height = Math.min(Math.max(cropBoxData.height, cropBoxData.minHeight), cropBoxData.maxHeight); // The width/height of auto crop area must large than "minWidth/Height"

            cropBoxData.width = Math.max(cropBoxData.minWidth, cropBoxData.width * autoCropArea);
            cropBoxData.height = Math.max(cropBoxData.minHeight, cropBoxData.height * autoCropArea);
            cropBoxData.left = canvasData.left + (canvasData.width - cropBoxData.width) / 2;
            cropBoxData.top = canvasData.top + (canvasData.height - cropBoxData.height) / 2;
            cropBoxData.oldLeft = cropBoxData.left;
            cropBoxData.oldTop = cropBoxData.top;
            this.initialCropBoxData = assign({}, cropBoxData);
        },
        limitCropBox: function limitCropBox(sizeLimited, positionLimited) {
            var options = this.options,
                containerData = this.containerData,
                canvasData = this.canvasData,
                cropBoxData = this.cropBoxData,
                limited = this.limited;
            var aspectRatio = options.aspectRatio;

            if (sizeLimited) {
                var minCropBoxWidth = Number(options.minCropBoxWidth) || 0;
                var minCropBoxHeight = Number(options.minCropBoxHeight) || 0;
                var maxCropBoxWidth = limited ? Math.min(containerData.width, canvasData.width, canvasData.width + canvasData.left, containerData.width - canvasData.left) : containerData.width;
                var maxCropBoxHeight = limited ? Math.min(containerData.height, canvasData.height, canvasData.height + canvasData.top, containerData.height - canvasData.top) : containerData.height; // The min/maxCropBoxWidth/Height must be less than container's width/height

                minCropBoxWidth = Math.min(minCropBoxWidth, containerData.width);
                minCropBoxHeight = Math.min(minCropBoxHeight, containerData.height);

                if (aspectRatio) {
                    if (minCropBoxWidth && minCropBoxHeight) {
                        if (minCropBoxHeight * aspectRatio > minCropBoxWidth) {
                            minCropBoxHeight = minCropBoxWidth / aspectRatio;
                        } else {
                            minCropBoxWidth = minCropBoxHeight * aspectRatio;
                        }
                    } else if (minCropBoxWidth) {
                        minCropBoxHeight = minCropBoxWidth / aspectRatio;
                    } else if (minCropBoxHeight) {
                        minCropBoxWidth = minCropBoxHeight * aspectRatio;
                    }

                    if (maxCropBoxHeight * aspectRatio > maxCropBoxWidth) {
                        maxCropBoxHeight = maxCropBoxWidth / aspectRatio;
                    } else {
                        maxCropBoxWidth = maxCropBoxHeight * aspectRatio;
                    }
                } // The minWidth/Height must be less than maxWidth/Height


                cropBoxData.minWidth = Math.min(minCropBoxWidth, maxCropBoxWidth);
                cropBoxData.minHeight = Math.min(minCropBoxHeight, maxCropBoxHeight);
                cropBoxData.maxWidth = maxCropBoxWidth;
                cropBoxData.maxHeight = maxCropBoxHeight;
            }

            if (positionLimited) {
                if (limited) {
                    cropBoxData.minLeft = Math.max(0, canvasData.left);
                    cropBoxData.minTop = Math.max(0, canvasData.top);
                    cropBoxData.maxLeft = Math.min(containerData.width, canvasData.left + canvasData.width) - cropBoxData.width;
                    cropBoxData.maxTop = Math.min(containerData.height, canvasData.top + canvasData.height) - cropBoxData.height;
                } else {
                    cropBoxData.minLeft = 0;
                    cropBoxData.minTop = 0;
                    cropBoxData.maxLeft = containerData.width - cropBoxData.width;
                    cropBoxData.maxTop = containerData.height - cropBoxData.height;
                }
            }
        },
        renderCropBox: function renderCropBox() {
            var options = this.options,
                containerData = this.containerData,
                cropBoxData = this.cropBoxData;

            if (cropBoxData.width > cropBoxData.maxWidth || cropBoxData.width < cropBoxData.minWidth) {
                cropBoxData.left = cropBoxData.oldLeft;
            }

            if (cropBoxData.height > cropBoxData.maxHeight || cropBoxData.height < cropBoxData.minHeight) {
                cropBoxData.top = cropBoxData.oldTop;
            }

            cropBoxData.width = Math.min(Math.max(cropBoxData.width, cropBoxData.minWidth), cropBoxData.maxWidth);
            cropBoxData.height = Math.min(Math.max(cropBoxData.height, cropBoxData.minHeight), cropBoxData.maxHeight);
            this.limit