如何实现此效果https://codepen.io/aravi-pen/pen/PyBpgY，使PhotoSwipe的灯箱阵列中的base64图像上的图像模糊不清？
HTML
<section class="wrapper">
<div class="aspect-ratio-fill">
<div class="progressiveMedia">
<canvas class="progressiveMedia__canvas" width="75" height="38.671875"></canvas>
<img class="progressiveMedia__image" data-src="http://staging.weate.ch.stage18.535e.blackmesh.com/poc/blurup/images/617902.jpg"/>
<img class="progressiveMedia__thumbnail" src="data:image/jpeg;base64,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" />
</div>
</div>
</section>
CSS
body {
background-color: #fefefe;
color: #000;
}
.wrapper {
max-width: 900px;
margin: 0 auto;
}
.aspect-ratio-fill {
position: relative;
display: block;
}
.progressiveMedia {
background-color: #eee;
display: block;
position: absolute;
top: 0;
left: 0;
height: 100%;
width: 100%;
}
.progressiveMedia.isImageLoaded > .progressiveMedia__image {
opacity: 1;
}
.progressiveMedia__thumbnail {
display: none;
}
.progressiveMedia__image,
.progressiveMedia__canvas {
border-radius: 3px;
display: block;
position: absolute;
top: 0;
left: 0;
height: 100%;
width: 100%;
}
.progressiveMedia__image {
opacity: 0;
transition: opacity 400ms 0ms;
z-index: 1;
}
.progressiveMedia.isImageLoaded .progressiveMedia__canvas{
visibility: hidden;
opacity: 0;
-webkit-transition: visibility 0s linear .5s,opacity .1s .4s;
transition: visibility 0s linear .5s,opacity .1s .4s;
}
JS
function init() {
const blurdelay = 1000;//The delay to see the fade in.
var blurRadius = 7;
var component = document.querySelector('.progressiveMedia');
var image = document.querySelector('.progressiveMedia__image');
var canvas = document.querySelector('.progressiveMedia__canvas');
var thumbnail = document.querySelector('.progressiveMedia__thumbnail');
var context = canvas.getContext('2d');
//The aspect-ratio-fill padding is set here.
var aspectRatioFill = document.querySelector('.aspect-ratio-fill');
var percentage = (thumbnail.naturalHeight / thumbnail.naturalWidth) * 100;
aspectRatioFill.style.paddingBottom = `${percentage}%`;
//Draw the thumbnail onto the canvas, then blur it
drawThumbnail(blurRadius);
//Load the image in. Once it's loaded, add a class to the component wrapper that fades in the image and fades out the canvas element.
image.src = image.dataset.src;
image.addEventListener('load', function onImageLoaded() {
image.removeEventListener('load', onImageLoaded);
// This delay is only set so the we can see the blur effect more clearly on page load
setTimeout(function () {
component.classList.add('isImageLoaded');
}, blurdelay);
});
//Draws the thumbnail into the canvas and blurs it
function drawThumbnail(blur) {
context
.drawImage(thumbnail, 0, 0, thumbnail.naturalWidth,
thumbnail.naturalHeight, 0, 0, canvas.width, canvas.height);
StackBlur.canvasRGBA(canvas, 0, 0, canvas.width, canvas.height, blur);
}
}
// Set a timeout so we make sure StackBlur is defined
setTimeout(init, 0);
/**
* StackBlur.js
* from https://github.com/flozz/StackBlur/
*/
(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.StackBlur = f()}})(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
/*
StackBlur - a fast almost Gaussian Blur For Canvas
Version: 0.5
Author: Mario Klingemann
Contact: [email protected]
Website: http://www.quasimondo.com/StackBlurForCanvas
Twitter: @quasimondo
In case you find this class useful - especially in commercial projects -
I am not totally unhappy for a small donation to my PayPal account
[email protected]
Or support me on flattr:
https://flattr.com/thing/72791/StackBlur-a-fast-almost-Gaussian-Blur-Effect-for-CanvasJavascript
Copyright (c) 2010 Mario Klingemann
Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
*/
var mul_table = [
512,512,456,512,328,456,335,512,405,328,271,456,388,335,292,512,
454,405,364,328,298,271,496,456,420,388,360,335,312,292,273,512,
482,454,428,405,383,364,345,328,312,298,284,271,259,496,475,456,
437,420,404,388,374,360,347,335,323,312,302,292,282,273,265,512,
497,482,468,454,441,428,417,405,394,383,373,364,354,345,337,328,
320,312,305,298,291,284,278,271,265,259,507,496,485,475,465,456,
446,437,428,420,412,404,396,388,381,374,367,360,354,347,341,335,
329,323,318,312,307,302,297,292,287,282,278,273,269,265,261,512,
505,497,489,482,475,468,461,454,447,441,435,428,422,417,411,405,
399,394,389,383,378,373,368,364,359,354,350,345,341,337,332,328,
324,320,316,312,309,305,301,298,294,291,287,284,281,278,274,271,
268,265,262,259,257,507,501,496,491,485,480,475,470,465,460,456,
451,446,442,437,433,428,424,420,416,412,408,404,400,396,392,388,
385,381,377,374,370,367,363,360,357,354,350,347,344,341,338,335,
332,329,326,323,320,318,315,312,310,307,304,302,299,297,294,292,
289,287,285,282,280,278,275,273,271,269,267,265,263,261,259];
var shg_table = [
9, 11, 12, 13, 13, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 17,
17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 18, 19,
19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 20, 20, 20,
20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 21,
21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21,
21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22,
22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22,
22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 23,
23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23,
23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23,
23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23,
23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24 ];
function processImage(img, canvas, radius, blurAlphaChannel)
{
if (typeof(img) == 'string') {
var img = document.getElementById(img);
}
else if (!img instanceof HTMLImageElement) {
return;
}
var w = img.naturalWidth;
var h = img.naturalHeight;
if (typeof(canvas) == 'string') {
var canvas = document.getElementById(canvas);
}
else if (!canvas instanceof HTMLCanvasElement) {
return;
}
canvas.style.width = w + 'px';
canvas.style.height = h + 'px';
canvas.width = w;
canvas.height = h;
var context = canvas.getContext('2d');
context.clearRect(0, 0, w, h);
context.drawImage(img, 0, 0);
if (isNaN(radius) || radius < 1) return;
if (blurAlphaChannel)
processCanvasRGBA(canvas, 0, 0, w, h, radius);
else
processCanvasRGB(canvas, 0, 0, w, h, radius);
}
function getImageDataFromCanvas(canvas, top_x, top_y, width, height)
{
if (typeof(canvas) == 'string')
var canvas = document.getElementById(canvas);
else if (!canvas instanceof HTMLCanvasElement)
return;
var context = canvas.getContext('2d');
var imageData;
try {
try {
imageData = context.getImageData(top_x, top_y, width, height);
} catch(e) {
// NOTE: this part is supposedly only needed if you want to work with local files
// so it might be okay to remove the whole try/catch block and just use
// imageData = context.getImageData(top_x, top_y, width, height);
try {
netscape.security.PrivilegeManager.enablePrivilege("UniversalBrowserRead");
imageData = context.getImageData(top_x, top_y, width, height);
} catch(e) {
alert("Cannot access local image");
throw new Error("unable to access local image data: " + e);
return;
}
}
} catch(e) {
alert("Cannot access image");
throw new Error("unable to access image data: " + e);
}
return imageData;
}
function processCanvasRGBA(canvas, top_x, top_y, width, height, radius)
{
if (isNaN(radius) || radius < 1) return;
radius |= 0;
var imageData = getImageDataFromCanvas(canvas, top_x, top_y, width, height);
imageData = processImageDataRGBA(imageData, top_x, top_y, width, height, radius);
canvas.getContext('2d').putImageData(imageData, top_x, top_y);
}
function processImageDataRGBA(imageData, top_x, top_y, width, height, radius)
{
var pixels = imageData.data;
var x, y, i, p, yp, yi, yw, r_sum, g_sum, b_sum, a_sum,
r_out_sum, g_out_sum, b_out_sum, a_out_sum,
r_in_sum, g_in_sum, b_in_sum, a_in_sum,
pr, pg, pb, pa, rbs;
var div = radius + radius + 1;
var w4 = width << 2;
var widthMinus1 = width - 1;
var heightMinus1 = height - 1;
var radiusPlus1 = radius + 1;
var sumFactor = radiusPlus1 * (radiusPlus1 + 1) / 2;
var stackStart = new BlurStack();
var stack = stackStart;
for (i = 1; i < div; i++)
{
stack = stack.next = new BlurStack();
if (i == radiusPlus1) var stackEnd = stack;
}
stack.next = stackStart;
var stackIn = null;
var stackOut = null;
yw = yi = 0;
var mul_sum = mul_table[radius];
var shg_sum = shg_table[radius];
for (y = 0; y < height; y++)
{
r_in_sum = g_in_sum = b_in_sum = a_in_sum = r_sum = g_sum = b_sum = a_sum = 0;
r_out_sum = radiusPlus1 * (pr = pixels[yi]);
g_out_sum = radiusPlus1 * (pg = pixels[yi+1]);
b_out_sum = radiusPlus1 * (pb = pixels[yi+2]);
a_out_sum = radiusPlus1 * (pa = pixels[yi+3]);
r_sum += sumFactor * pr;
g_sum += sumFactor * pg;
b_sum += sumFactor * pb;
a_sum += sumFactor * pa;
stack = stackStart;
for (i = 0; i < radiusPlus1; i++)
{
stack.r = pr;
stack.g = pg;
stack.b = pb;
stack.a = pa;
stack = stack.next;
}
for (i = 1; i < radiusPlus1; i++)
{
p = yi + ((widthMinus1 < i ? widthMinus1 : i) << 2);
r_sum += (stack.r = (pr = pixels[p])) * (rbs = radiusPlus1 - i);
g_sum += (stack.g = (pg = pixels[p+1])) * rbs;
b_sum += (stack.b = (pb = pixels[p+2])) * rbs;
a_sum += (stack.a = (pa = pixels[p+3])) * rbs;
r_in_sum += pr;
g_in_sum += pg;
b_in_sum += pb;
a_in_sum += pa;
stack = stack.next;
}
stackIn = stackStart;
stackOut = stackEnd;
for (x = 0; x < width; x++)
{
pixels[yi+3] = pa = (a_sum * mul_sum) >> shg_sum;
if (pa != 0)
{
pa = 255 / pa;
pixels[yi] = ((r_sum * mul_sum) >> shg_sum) * pa;
pixels[yi+1] = ((g_sum * mul_sum) >> shg_sum) * pa;
pixels[yi+2] = ((b_sum * mul_sum) >> shg_sum) * pa;
} else {
pixels[yi] = pixels[yi+1] = pixels[yi+2] = 0;
}
r_sum -= r_out_sum;
g_sum -= g_out_sum;
b_sum -= b_out_sum;
a_sum -= a_out_sum;
r_out_sum -= stackIn.r;
g_out_sum -= stackIn.g;
b_out_sum -= stackIn.b;
a_out_sum -= stackIn.a;
p = (yw + ((p = x + radius + 1) < widthMinus1 ? p : widthMinus1)) << 2;
r_in_sum += (stackIn.r = pixels[p]);
g_in_sum += (stackIn.g = pixels[p+1]);
b_in_sum += (stackIn.b = pixels[p+2]);
a_in_sum += (stackIn.a = pixels[p+3]);
r_sum += r_in_sum;
g_sum += g_in_sum;
b_sum += b_in_sum;
a_sum += a_in_sum;
stackIn = stackIn.next;
r_out_sum += (pr = stackOut.r);
g_out_sum += (pg = stackOut.g);
b_out_sum += (pb = stackOut.b);
a_out_sum += (pa = stackOut.a);
r_in_sum -= pr;
g_in_sum -= pg;
b_in_sum -= pb;
a_in_sum -= pa;
stackOut = stackOut.next;
yi += 4;
}
yw += width;
}
for (x = 0; x < width; x++)
{
g_in_sum = b_in_sum = a_in_sum = r_in_sum = g_sum = b_sum = a_sum = r_sum = 0;
yi = x << 2;
r_out_sum = radiusPlus1 * (pr = pixels[yi]);
g_out_sum = radiusPlus1 * (pg = pixels[yi+1]);
b_out_sum = radiusPlus1 * (pb = pixels[yi+2]);
a_out_sum = radiusPlus1 * (pa = pixels[yi+3]);
r_sum += sumFactor * pr;
g_sum += sumFactor * pg;
b_sum += sumFactor * pb;
a_sum += sumFactor * pa;
stack = stackStart;
for (i = 0; i < radiusPlus1; i++)
{
stack.r = pr;
stack.g = pg;
stack.b = pb;
stack.a = pa;
stack = stack.next;
}
yp = width;
for (i = 1; i <= radius; i++)
{
yi = (yp + x) << 2;
r_sum += (stack.r = (pr = pixels[yi])) * (rbs = radiusPlus1 - i);
g_sum += (stack.g = (pg = pixels[yi+1])) * rbs;
b_sum += (stack.b = (pb = pixels[yi+2])) * rbs;
a_sum += (stack.a = (pa = pixels[yi+3])) * rbs;
r_in_sum += pr;
g_in_sum += pg;
b_in_sum += pb;
a_in_sum += pa;
stack = stack.next;
if(i < heightMinus1)
{
yp += width;
}
}
yi = x;
stackIn = stackStart;
stackOut = stackEnd;
for (y = 0; y < height; y++)
{
p = yi << 2;
pixels[p+3] = pa = (a_sum * mul_sum) >> shg_sum;
if (pa > 0)
{
pa = 255 / pa;
pixels[p] = ((r_sum * mul_sum) >> shg_sum) * pa;
pixels[p+1] = ((g_sum * mul_sum) >> shg_sum) * pa;
pixels[p+2] = ((b_sum * mul_sum) >> shg_sum) * pa;
} else {
pixels[p] = pixels[p+1] = pixels[p+2] = 0;
}
r_sum -= r_out_sum;
g_sum -= g_out_sum;
b_sum -= b_out_sum;
a_sum -= a_out_sum;
r_out_sum -= stackIn.r;
g_out_sum -= stackIn.g;
b_out_sum -= stackIn.b;
a_out_sum -= stackIn.a;
p = (x + (((p = y + radiusPlus1) < heightMinus1 ? p : heightMinus1) * width)) << 2;
r_sum += (r_in_sum += (stackIn.r = pixels[p]));
g_sum += (g_in_sum += (stackIn.g = pixels[p+1]));
b_sum += (b_in_sum += (stackIn.b = pixels[p+2]));
a_sum += (a_in_sum += (stackIn.a = pixels[p+3]));
stackIn = stackIn.next;
r_out_sum += (pr = stackOut.r);
g_out_sum += (pg = stackOut.g);
b_out_sum += (pb = stackOut.b);
a_out_sum += (pa = stackOut.a);
r_in_sum -= pr;
g_in_sum -= pg;
b_in_sum -= pb;
a_in_sum -= pa;
stackOut = stackOut.next;
yi += width;
}
}
return imageData;
}
function processCanvasRGB(canvas, top_x, top_y, width, height, radius)
{
if (isNaN(radius) || radius < 1) return;
radius |= 0;
var imageData = getImageDataFromCanvas(canvas, top_x, top_y, width, height);
imageData = processImageDataRGB(imageData, top_x, top_y, width, height, radius);
canvas.getContext('2d').putImageData(imageData, top_x, top_y);
}
function processImageDataRGB(imageData, top_x, top_y, width, height, radius)
{
var pixels = imageData.data;
var x, y, i, p, yp, yi, yw, r_sum, g_sum, b_sum,
r_out_sum, g_out_sum, b_out_sum,
r_in_sum, g_in_sum, b_in_sum,
pr, pg, pb, rbs;
var div = radius + radius + 1;
var w4 = width << 2;
var widthMinus1 = width - 1;
var heightMinus1 = height - 1;
var radiusPlus1 = radius + 1;
var sumFactor = radiusPlus1 * (radiusPlus1 + 1) / 2;
var stackStart = new BlurStack();
var stack = stackStart;
for (i = 1; i < div; i++)
{
stack = stack.next = new BlurStack();
if (i == radiusPlus1) var stackEnd = stack;
}
stack.next = stackStart;
var stackIn = null;
var stackOut = null;
yw = yi = 0;
var mul_sum = mul_table[radius];
var shg_sum = shg_table[radius];
for (y = 0; y < height; y++)
{
r_in_sum = g_in_sum = b_in_sum = r_sum = g_sum = b_sum = 0;
r_out_sum = radiusPlus1 * (pr = pixels[yi]);
g_out_sum = radiusPlus1 * (pg = pixels[yi+1]);
b_out_sum = radiusPlus1 * (pb = pixels[yi+2]);
r_sum += sumFactor * pr;
g_sum += sumFactor * pg;
b_sum += sumFactor * pb;
stack = stackStart;
for (i = 0; i < radiusPlus1; i++)
{
stack.r = pr;
stack.g = pg;
stack.b = pb;
stack = stack.next;
}
for (i = 1; i < radiusPlus1; i++)
{
p = yi + ((widthMinus1 < i ? widthMinus1 : i) << 2);
r_sum += (stack.r = (pr = pixels[p])) * (rbs = radiusPlus1 - i);
g_sum += (stack.g = (pg = pixels[p+1])) * rbs;
b_sum += (stack.b = (pb = pixels[p+2])) * rbs;
r_in_sum += pr;
g_in_sum += pg;
b_in_sum += pb;
stack = stack.next;
}
stackIn = stackStart;
stackOut = stackEnd;
for (x = 0; x < width; x++)
{
pixels[yi] = (r_sum * mul_sum) >> shg_sum;
pixels[yi+1] = (g_sum * mul_sum) >> shg_sum;
pixels[yi+2] = (b_sum * mul_sum) >> shg_sum;
r_sum -= r_out_sum;
g_sum -= g_out_sum;
b_sum -= b_out_sum;
r_out_sum -= stackIn.r;
g_out_sum -= stackIn.g;
b_out_sum -= stackIn.b;
p = (yw + ((p = x + radius + 1) < widthMinus1 ? p : widthMinus1)) << 2;
r_in_sum += (stackIn.r = pixels[p]);
g_in_sum += (stackIn.g = pixels[p+1]);
b_in_sum += (stackIn.b = pixels[p+2]);
r_sum += r_in_sum;
g_sum += g_in_sum;
b_sum += b_in_sum;
stackIn = stackIn.next;
r_out_sum += (pr = stackOut.r);
g_out_sum += (pg = stackOut.g);
b_out_sum += (pb = stackOut.b);
r_in_sum -= pr;
g_in_sum -= pg;
b_in_sum -= pb;
stackOut = stackOut.next;
yi += 4;
}
yw += width;
}
for (x = 0; x < width; x++)
{
g_in_sum = b_in_sum = r_in_sum = g_sum = b_sum = r_sum = 0;
yi = x << 2;
r_out_sum = radiusPlus1 * (pr = pixels[yi]);
g_out_sum = radiusPlus1 * (pg = pixels[yi+1]);
b_out_sum = radiusPlus1 * (pb = pixels[yi+2]);
r_sum += sumFactor * pr;
g_sum += sumFactor * pg;
b_sum += sumFactor * pb;
stack = stackStart;
for (i = 0; i < radiusPlus1; i++)
{
stack.r = pr;
stack.g = pg;
stack.b = pb;
stack = stack.next;
}
yp = width;
for (i = 1; i <= radius; i++)
{
yi = (yp + x) << 2;
r_sum += (stack.r = (pr = pixels[yi])) * (rbs = radiusPlus1 - i);
g_sum += (stack.g = (pg = pixels[yi+1])) * rbs;
b_sum += (stack.b = (pb = pixels[yi+2])) * rbs;
r_in_sum += pr;
g_in_sum += pg;
b_in_sum += pb;
stack = stack.next;
if(i < heightMinus1)
{
yp += width;
}
}
yi = x;
stackIn = stackStart;
stackOut = stackEnd;
for (y = 0; y < height; y++)
{
p = yi << 2;
pixels[p] = (r_sum * mul_sum) >> shg_sum;
pixels[p+1] = (g_sum * mul_sum) >> shg_sum;
pixels[p+2] = (b_sum * mul_sum) >> shg_sum;
r_sum -= r_out_sum;
g_sum -= g_out_sum;
b_sum -= b_out_sum;
r_out_sum -= stackIn.r;
g_out_sum -= stackIn.g;
b_out_sum -= stackIn.b;
p = (x + (((p = y + radiusPlus1) < heightMinus1 ? p : heightMinus1) * width)) << 2;
r_sum += (r_in_sum += (stackIn.r = pixels[p]));
g_sum += (g_in_sum += (stackIn.g = pixels[p+1]));
b_sum += (b_in_sum += (stackIn.b = pixels[p+2]));
stackIn = stackIn.next;
r_out_sum += (pr = stackOut.r);
g_out_sum += (pg = stackOut.g);
b_out_sum += (pb = stackOut.b);
r_in_sum -= pr;
g_in_sum -= pg;
b_in_sum -= pb;
stackOut = stackOut.next;
yi += width;
}
}
return imageData;
}
function BlurStack()
{
this.r = 0;
this.g = 0;
this.b = 0;
this.a = 0;
this.next = null;
}
module.exports = {
image: processImage,
canvasRGBA: processCanvasRGBA,
canvasRGB: processCanvasRGB,
imageDataRGBA: processImageDataRGBA,
imageDataRGB: processImageDataRGB
};
},{}]},{},[1])(1)
});
虽然可以在PhotoSwipe数组中添加Base64图像作为占位符，但是很难看到如何将图像放入画布，然后使该画布模糊。
有人知道要挂起哪个事件才能使它起作用吗？