Download Pixiv Canvas-Based Animated Images and Generate its Sprite Sheet

pixiv_download.js

var xhr = new XMLHttpRequest();
xhr.open("GET", pixiv.context.ugokuIllustData.src, true);
xhr.responseType = "blob";
xhr.onload = function() {
	var blob = this.response;
	var a = document.createElement("a");
	a.href = URL.createObjectURL(blob);
	a.setAttribute("download", "compressed.zip");
	a.click();
	console.log(blob);
};
xhr.send();

sprite_sheet.m

clear;

folder = 'compressed';
scale = 0.25;
files = dir(folder);
n = length(files);

for i = 1:n
    file = files(i);
    path = [file.folder, '/', file.name];
    if endsWith(path, 'jpg')
        im = imread(path);
        im = imresize(im, scale);
        if exist('ims', 'var')
            ims = [ims, im];
        else
            ims = im;
        end
    end
end

imwrite(gray2rgb(ims), [folder, '.png']);

function rgb = gray2rgb(gray)
    rgb = cat(3, gray, gray, gray);
end