compress-base64
Version:
compress base64
93 lines (92 loc) • 4.12 kB
JavaScript
/**
* compress-base64 v7.0.10 by sunsilent
* @license MIT
**/
(function(root, factory) {
if ('object' == typeof exports && 'object' == typeof module) module.exports = factory();
else if ('function' == typeof define && define.amd) define([], factory);
else if ('object' == typeof exports) exports["CompressBase64"] = factory();
else root["CompressBase64"] = factory();
})(self, function() {
return function() {
"use strict";
var __webpack_require__ = {};
!function() {
__webpack_require__.d = function(exports1, definition) {
for(var key in definition)if (__webpack_require__.o(definition, key) && !__webpack_require__.o(exports1, key)) Object.defineProperty(exports1, key, {
enumerable: true,
get: definition[key]
});
};
}();
!function() {
__webpack_require__.o = function(obj, prop) {
return Object.prototype.hasOwnProperty.call(obj, prop);
};
}();
!function() {
__webpack_require__.r = function(exports1) {
if ('undefined' != typeof Symbol && Symbol.toStringTag) Object.defineProperty(exports1, Symbol.toStringTag, {
value: 'Module'
});
Object.defineProperty(exports1, '__esModule', {
value: true
});
};
}();
var __webpack_exports__ = {};
__webpack_require__.r(__webpack_exports__);
__webpack_require__.d(__webpack_exports__, {
default: function() {
return compress;
}
});
var step = 0.001;
function compress(base64, options) {
var _options_type = options.type, type = void 0 === _options_type ? 'image/jpeg' : _options_type, width = options.width, height = options.height, _options_min = options.min, min = void 0 === _options_min ? 0 : _options_min, _options_max = options.max, max = void 0 === _options_max ? 200 : _options_max, crossOrigin = options.crossOrigin, quality = options.quality;
return new Promise(function(resolve, reject) {
var tq = quality || 0.8;
var img = new Image();
img.src = base64;
if ('string' == typeof crossOrigin) img.setAttribute('crossOrigin', crossOrigin);
var tw = width;
var th = height;
img.onload = function() {
if (isNaN(tw) && isNaN(th)) {
tw = img.width;
th = img.height;
} else {
if (!isNaN(tw) && isNaN(th)) th = tw * img.height / img.width;
if (isNaN(tw) && !isNaN(th)) tw = th * img.width / img.height;
}
img.width = tw;
img.height = th;
var canvas = document.createElement('canvas');
var ctx = canvas.getContext('2d');
canvas.width = tw;
canvas.height = th;
ctx.clearRect(0, 0, canvas.width, canvas.height);
ctx.drawImage(img, 0, 0, canvas.width, canvas.height);
var _$base64 = canvas.toDataURL(type, tq);
while(_$base64.length / 1024 > max){
if (tq <= step) {
_$base64 = canvas.toDataURL(type, step);
break;
}
tq -= step;
_$base64 = canvas.toDataURL(type, tq);
}
while(_$base64.length / 1024 < min){
tq += step;
_$base64 = canvas.toDataURL(type, tq);
}
resolve(_$base64);
};
img.onerror = function(error) {
reject(error);
};
});
}
return __webpack_exports__;
}();
});