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bangumi blur image

a tool for bluring image before upload

// ==UserScript==
// @name        bangumi blur image 
// @namespace   https://github.com/22earth
// @description a tool for bluring image before upload
// @include     /^https?:\/\/(bangumi|bgm|chii)\.(tv|in)\/.*(upload_img|new)$/
// @grant       GM_addStyle
// @version     0.2.4
// @note        0.2 add loading and main entry function
// ==/UserScript==


/* 
 * greasyfork.org don't allow code uses an unapproved external script
 * copy StackBlur source code at below
 */
;(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:     mario@quasimondo.com
    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
    mario@quasimondo.de
    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 (typeof HTMLImageElement !== 'undefined' && !img instanceof HTMLImageElement) {
        return;
    }
    var w = img.naturalWidth;
    var h = img.naturalHeight;

    if (typeof(canvas) == 'string') {
        var canvas = document.getElementById(canvas);
    }
    else if (typeof HTMLCanvasElement !== 'undefined' && !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 (typeof HTMLCanvasElement !== 'undefined' && !canvas instanceof HTMLCanvasElement)
        return;

    var context = canvas.getContext('2d');
    var imageData;

    try {
        try {
            imageData = context.getImageData(top_x, top_y, width, height);
        } catch(e) {
            throw new Error("unable to access local image data: " + e);
            return;
        }
    } catch(e) {
        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)
});

;(function() {
  function addInputFile($target) {
    var $input = document.createElement('input');
    $input.type = 'file';
    if ($target) {
      $target.parentElement.insertBefore($input, $target.nextElementSibling);
    }
  }
  function addStyle(css) {
    if (css) {
      GM_addStyle(css);
    } else {
      GM_addStyle([
        '#amount { padding-left: 10px; border: 0; color: #f6931f; font-size: 20px; font-weight: bold; }',
        '#reset { display: inline-block; text-align: center; width: 60px; height: 30px; line-height: 30px; font-size: 18px; background-color: #f09199; text-decoration: none; color: #fff; margin-left: 50px; margin-bottom: 30px; border-radius: 5px; box-shadow:1px 1px 2px #333; }',
        'canvas:active { cursor: crosshair; }',
        '#preview { display: block; }',
        '.blur-loading { width: 208px; height: 13px; background-image: url("/img/loadingAnimation.gif"); }'
      ].join(''));
    }
  }
  function insertBlurInfo($target) {
    const rawHTML = `
    <label for="amount">Blur width and radius:</label>
    <input id="amount" type="text" readonly>
    <br>
    <input id="slider-width" type="range" value="20" name="width" min="1" max="100"><canvas></canvas>
    <br>
    <input id="slider-radius" type="range" value="10" name="radius" min="1" max="100">
    <br>
    <a href="#" id="reset">reset</a>
  `;
    var $info = document.createElement('div');
    $info.classList.add('blur-info');
    $info.innerHTML = rawHTML;
    if ($target) {
      $target.parentElement.insertBefore($info, $target.nextElementSibling);
    }
  }
  function changeInfo($width, $radius) {
    var $info = document.querySelector('#amount');
    var radius = $radius.value;
    var width = $width.value;
    $info.value = width + ', ' + radius;
  }
  function getMousePos(canvas, evt) {
    var rect = canvas.getBoundingClientRect();
    return {
      x: (evt.clientX - rect.left) / (rect.right - rect.left) * canvas.width,
      y: (evt.clientY - rect.top) / (rect.bottom - rect.top) * canvas.height
    };
  }
  function drawRec($width) {
    var $canvas = $width.nextElementSibling;
    var ctx = $canvas.getContext('2d');
    var width = Number($width.value);
    $canvas.width = width * 1.4;
    $canvas.height = width * 1.4;
    ctx.strokeStyle = '#f09199';
    ctx.strokeRect(0.2 * width, 0.2 * width, width, width);
    window.dispatchEvent(new Event('resize'));
  }
  function previewFile($file, $blurInfo) {
    //var $file = document.querySelector('input[type = file]')
    var $canvas = document.createElement('canvas');
    var $radius = $blurInfo.querySelector('#slider-radius');
    var $width = $blurInfo.querySelector('#slider-width');
    $canvas.id = 'preview';
    $canvas.width = 8;
    $canvas.height = 10;
    var ctx = $canvas.getContext('2d');
    $blurInfo.insertBefore($canvas, $blurInfo.firstChild);
    var $img = new Image();
    $img.addEventListener('load', function () {
      $canvas.width = $img.width;
      $canvas.height = $img.height;
      ctx.drawImage($img, 0, 0);
      window.dispatchEvent(new Event('resize'));  // let img cut tool at right position
    }, false);
    blur($canvas);
    $file.addEventListener('change', loadImgData, false);

    function blur(el) {
      var isDrawing;
      var ctx = el.getContext('2d');
      el.onmousedown = function (e) {
        isDrawing = true;
        var pos = getMousePos(el, e);
        ctx.moveTo(pos.x, pos.y);
      };
      el.onmousemove = function (e) {
        if (isDrawing) {
          //ctx.lineTo(e.layerX, e.layerY);
          //ctx.stroke();
          var radius = Number($radius.value);
          var width = Number($width.value);
          var pos = getMousePos(el, e);
          StackBlur.canvasRGBA(el, pos.x - width / 2, pos.y - width / 2, width, width, radius);
        }
      };
      el.onmouseup = function () {
        isDrawing = false;
      };
    }
    function loadImgData() {
      var file = $file.files[0];
      var reader = new FileReader();
      reader.addEventListener('load', function () {
        $img.src = reader.result;
      }, false);
      if (file) {
        reader.readAsDataURL(file);
      }
    }
    document.querySelector('#reset').addEventListener('click', function (e) {
      e.preventDefault()
      var file = $file.files[0];
      var $fillForm = document.querySelector('.fill-form');
      if (file) {
        $file.dispatchEvent(new Event('change'));
      } else if ($fillForm) {
        $fillForm.dispatchEvent(new Event('click'));
      }
    });
  }

  function sendFormDataPic($form, dataURL) {
    var genString = Array.apply(null, Array(5)).map(function(){
      return (function(charset){
        return charset.charAt(Math.floor(Math.random()*charset.length));
      }('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'));
    }).join('');
    function dataURItoBlob(dataURI) {
      // convert base64/URLEncoded data component to raw binary data held in a string
      var byteString;
      if (dataURI.split(',')[0].indexOf('base64') >= 0)
        byteString = atob(dataURI.split(',')[1]);
      else
        byteString = decodeURI(dataURI.split(',')[1]);  // instead of unescape
      // separate out the mime component
      var mimeString = dataURI.split(',')[0].split(':')[1].split(';')[0];
      // write the bytes of the string to a typed array
      var ia = new Uint8Array(byteString.length);
      for (var i = 0; i < byteString.length; i++) {
        ia[i] = byteString.charCodeAt(i);
      }
      return new Blob([ia], {type:mimeString});
    }
    function dataURLtoFile(dataurl, filename) {
      var arr = dataurl.split(','), mime = arr[0].match(/:(.*?);/)[1],
        bstr = atob(arr[1]), n = bstr.length, u8arr = new Uint8Array(n);
      while(n--){
        u8arr[n] = bstr.charCodeAt(n);
      }
      return new File([u8arr], filename, {type:mime});
    }
    // loading effect
    var $submit = $form.querySelector('[type=submit]');
    $submit.style.display = 'none';
    var $loading = document.createElement('div');
    $loading.classList.add('blur-loading');
    var $blurInfo = document.querySelector('.blur-info');
    $form.parentElement.insertBefore($loading, $blurInfo);
    // ajax 
    var fd = new FormData($form);
    var $file = $form.querySelector('input[type=file]');
    var inputFileName = $file.name ? $file.name : 'picfile';
    fd.set(inputFileName, dataURItoBlob(dataURL), genString + '.png');
    var $submit = $form.querySelector('[name=submit]')
    if ($submit && $submit.name && $submit.value) {
      fd.set($submit.name, $submit.value)
    }
    var xhr = new XMLHttpRequest();
    xhr.open($form.method.toLowerCase(), $form.action, true);
    xhr.onreadystatechange = function () {
      var _location;
      //console.log(xhr);
      if(xhr.readyState === 2 && xhr.status === 200){
        _location = xhr.responseURL;
        $loading.style.display = 'none';
        $submit.style.display = '';
        if(_location) {
          location.assign(_location);
        }
      }
    };
    xhr.send(fd);
    // clone form submit
    /*
     *var $cloneForm = $form.cloneNode(true)
     *var $file = $cloneForm.querySelector('input[type=file]')
     *$file.files[0] = dataURLtoFile(dataURL, genString + '.png')
     */
  }

  function init() {
    // gm init dom
    addStyle();
    var fs = [].slice.call(document.forms).filter(function(elem) {
      return elem.querySelector('input[type=file]');
    });
    insertBlurInfo(fs[0]);  // end add dom and css
    // blur
    var $radius = document.querySelector('#slider-radius');
    var $width = document.querySelector('#slider-width');
    window.addEventListener('load', function (e) {
      drawRec($width);
      changeInfo($width, $radius);
    }, false);
    var $file = document.querySelector('input[type = file]');
    var $blurInfo = document.querySelector('.blur-info');
    $blurInfo.addEventListener('change', function(e) {
      if (e.target.tagName.toLowerCase() === 'input') {
        changeInfo($width, $radius);
      }
      if (e.target.name === 'width') {
        drawRec($width);
      }
    }, false);
    previewFile($file, $blurInfo);

    fs.length && fs[0].addEventListener('submit', function (e) {
      var $canvas = document.querySelector('#preview');
      if (!$canvas) {
        return undefined;
      }
      if ($canvas.width === 8 && $canvas.height === 10) {
        return undefined;
      }
      e.preventDefault();
      var dataURL = document.querySelector('#preview').toDataURL('image/png', 1);
      sendFormDataPic(this, dataURL);
    }, false);
  }

  init();
}());