danbooruに画像をダウンロードするボタンを追加する。画像にはタグ(XP Keywords)が付与される。Picasa3と相性抜群。
Od
// ==UserScript==
// @name Downbooru
// @name:en Downbooru
// @namespace https://greasyfork.org/ja/scripts/29802-downbooru
// @version 2.0
// @description danbooruに画像をダウンロードするボタンを追加する。画像にはタグ(XP Keywords)が付与される。Picasa3と相性抜群。
// @description PNGはExifが無いためJPGに変換。サイズの大きい画像は縮小される。
// @description:en donwloads an image added tags from danbooru
// @author You
// @match *://danbooru.donmai.us$
// @match *://danbooru.donmai.us/posts*
// @grant none
// @require http://ajax.googleapis.com/ajax/libs/jquery/1.5.2/jquery.min.js
// ==/UserScript==
//参考:canvas https://blog.agektmr.com/2013/09/canvas-png-blob.html
//参考:deferred http://hamalog.tumblr.com/post/5159447047/jquerydeferredって何
//参考:http://qiita.com/geek_duck/items/2db28daa9e27df9b861d
(function () {
var host = window.location.host;
(function () {
var btn_prt = [];
switch (host) {
case 'danbooru.donmai.us':
$('[data-id]').each(function () {
btn_prt.push($(this));
});
}
for (var i in btn_prt) {
setButton(btn_prt[i]);
}
return;
})();
function setButton(btn_prt) {
var tag_name = btn_prt.get(0).tagName;
var button = $('<button>');
switch (tag_name) {
case 'SECTION':
button.text('Download');
break;
case 'ARTICLE':
button.text('DL').attr('style', 'position:absolute; right:0; bottom:0; opacity:0.5;');
button.hover(function () {
button.attr('style', 'position:absolute; right:0; bottom:0; opacity:1;');
}, function () {
button.attr('style', 'position:absolute; right:0; bottom:0; opacity:0.5;');
});
break;
}
button.click(function () {
switch (host) {
case 'danbooru.donmai.us':
var src = btn_prt.attr('data-file-url');
var tags = btn_prt.attr('data-tags').split(' ');
var file = "danbooru" + btn_prt.attr('data-id') + ".jpg";
}
switch (tag_name) {
case 'SECTION':
button.text('Generating...').attr("disabled", true);
break;
case 'ARTICLE':
button.text('...').attr("disabled", true);
break;
}
downloadImageWithTags(src, tags, file);
switch (tag_name) {
case 'SECTION':
button.html('<s>Download</s>');
break;
case 'ARTICLE':
button.html('<s>DL</s>').attr('style', 'position:absolute; right:0; bottom:0; opacity:1;');
break;
}
});
btn_prt.append(button);
return;
}
function downloadImageWithTags(src, tags, name) {
var exif = createExif(tags);
getImgDataurl(src).then(function (dataurl) {
var blob = insertExif(exif, dataurl);
var a = document.createElement('a');
a.href = window.URL.createObjectURL(blob);
a.download = name;
a.click();
return;
});
}
function getImgDataurl(url) {
var dfd = new $.Deferred();
var img = new Image();
img.src = url;
var canvas = document.createElement('canvas');
canvas.setAttribute('width', img.width);
canvas.setAttribute('height', img.height);
var ctx = canvas.getContext('2d');
img.onload = function () {
ctx.drawImage(img, 0, 0);
var jpg_src = canvas.toDataURL('image/jpeg');
//画像が大きすぎる場合、width850pxで再todataURL
if (jpg_src.split(',')[1]) {
dfd.resolve(jpg_src);
} else {
var smallWidth = 850;
var smallheight = 850 * img.height / img.width;
canvas.setAttribute('width', smallWidth);
canvas.setAttribute('height', smallheight);
ctx.drawImage(img, 0, 0, img.width, img.height, 0, 0, smallWidth, smallheight);
jpg_src = canvas.toDataURL('image/jpeg');
dfd.resolve(jpg_src);
}
};
return dfd.promise();
}
function createExif(list) {
var bim = "50686f746f73686f7020332e30003842494d040400000000";
var hex_list = [];
for (var i = 0; i < list.length; i++) {
hex_list[i] = strToHex(list[i]);
}
var tags = "1c021900" + tagLength(hex_list[0]) + hex_list[0] + "1c020000020004";
for (var i = 1; i < hex_list.length; i++) {
tags = tags + "1c021900" + tagLength(hex_list[i]) + hex_list[i];
}
tags = wholeTagLength(tags) + tags;
//XX XX [BIM] [TAGS]
var seg_len = (2 + bim.length / 2 + tags.length / 2).toString(16);
if (seg_len.length > 4) {
console.log("タグのデータ量が限界を超えました");
return;
}
seg_len = "000" + seg_len;
seg_len = seg_len.slice(-4);
var exif = "ffed" + seg_len + bim + tags;
return exif;
}
function insertExif(exif, dataurl) {
var bin = atob(dataurl.split(",")[1]);
var buffer = new Uint8Array(bin.length + exif.length / 2);
for (var i = 0; i < 20; i++) {
buffer[i] = bin.charCodeAt(i);
}
for (var bf_i = 20, ex_j = 0; ex_j < exif.length / 2; bf_i++,
ex_j++) {
buffer[bf_i] = parseInt(exif.slice(ex_j * 2, ex_j * 2 + 2), 16);
}
for (var bf_i = 20 + exif.length / 2, bin_j = 20; bin_j < bin.length; bf_i++,
bin_j++) {
buffer[bf_i] = bin.charCodeAt(bin_j);
}
var blob = new Blob([buffer.buffer], {
type: 'image/jpeg'
});
return blob;
}
//引数はhexで
function tagLength(str) {
var len = (str.length / 2).toString(16);
len = ("0" + len).slice(-2);
return len;
}
//引数はhexで
function wholeTagLength(str) {
var len = (str.length / 2).toString(16);
len = ("000" + len).slice(-4);
return len;
}
function strToHex(str) {
var hex = "";
for (var i = 0; i < str.length; i++) {
hex = hex + str.charCodeAt(i).toString(16);
}
return hex;
}
function strToU8(str) {
var buffer = new Uint8Array(str.length);
for (var i = 0; i < buffer.length; i++) {
buffer[i] = str.charCodeAt(i);
}
return buffer;
}
function hexToU8(str) {
var buffer = new Uint8Array(str.length / 2);
for (var i = 0; i < buffer.length; i++) {
buffer[i] = parseInt(str.slice(i * 2, i * 2 + 2), 16);
}
return buffer;
}
//テスト用 16進数文字列をアルファベットに変換する
function hexToChar(str) {
var char = "";
for (var i = 0; i < str.length / 2; i++) {
//4a→74→J
char = char + String.fromCharCode(parseInt(str.slice(i * 2, i * 2 + 2), 16));
}
return char;
}
}
)();