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moshroom.js

javascript:(function(){var g=function(c){return document.getElementById(c?"hplogo":"lga")},g={i:g(0),d:g(1),w:g(1).naturalWidth,h:g(1).naturalHeight},d=document.createElement("canvas"),o=d.getContext("2d"),a=g.i.querySelector("a"),e=5;d.setAttribute("width",g.w+"px");d.setAttribute("height",g.h+"px");d.setAttribute("style",g.d.getAttribute("style"));o.drawImage(g.d,0,0);a.innerHTML="";a.appendChild(d);for(var k=0;k<g.h;k+=e){var f=(e<=g.h-k)?e:g.h-k;for(var l=0;l<g.w;l+=e){var m=(e<=g.w-l)?e:g.w-l,b=[0,0,0],n=o.getImageData(l,k,m,f).data;for(var j=0;j<n.length;j+=4){b[0]+=n[j];b[1]+=n[j+1];b[2]+=n[j+2]}var i=n.length/4;b[0]=Math.floor(b[0]/i);b[1]=Math.floor(b[1]/i);b[2]=Math.floor(b[2]/i);o.clearRect(l,k,m,f);o.fillStyle="rgb("+b.join(",")+")";o.fillRect(l,k,m,f)}}}());

moshroom.source.js

// yuicompressor moshroom.js | pbcopy
javascript:
(function () {
  var tar = function (a) { return document.getElementById(a?'hplogo':'lga') },
      tar = { i : tar(0), d : tar(1), w : tar(1).naturalWidth, h : tar(1).naturalHeight },
      cvs = document.createElement('canvas'),
      ctx = cvs.getContext('2d'),
      sub = tar.i.querySelector('a'),
      box = 5;
  cvs.setAttribute('width', tar.w + 'px');
  cvs.setAttribute('height', tar.h + 'px');
  cvs.setAttribute('style', tar.d.getAttribute('style'));
  ctx.drawImage(tar.d, 0, 0);
  sub.innerHTML = '';
  sub.appendChild(cvs);
  for (var y = 0; y < tar.h; y += box) {
    var h = (box <= tar.h - y) ? box : tar.h - y;
    for (var x = 0; x < tar.w; x += box) {
      var w = (box <= tar.w - x) ? box : tar.w - x,
        col = [0, 0, 0],
        dat = ctx.getImageData(x, y, w, h).data;
      for (var z = 0; z < dat.length; z += 4) {
        col[0] += dat[z];
        col[1] += dat[z+1];
        col[2] += dat[z+2];
      }
      var c = dat.length/4;
      col[0] = Math.floor(col[0] / c);
      col[1] = Math.floor(col[1] / c);
      col[2] = Math.floor(col[2] / c);
      ctx.clearRect(x, y, w, h);
      ctx.fillStyle = 'rgb(' + col.join(',') + ')';
      ctx.fillRect(x, y, w, h);
    }
  }
}());