gistfile1.js

var pasteCatcher;
if (!window.Clipboard) {
  pasteCatcher = document.createElement("div");

  // Firefox allows images to be pasted into contenteditable elements
  pasteCatcher.setAttribute("contenteditable", "");

  // We can hide the element and append it to the body,
  pasteCatcher.style.opacity = 0;
  //No Space LOL!
  pasteCatcher.style.position="absolute";
  document.body.appendChild(pasteCatcher);

  // as long as we make sure it is always in focus
  pasteCatcher.focus();
  document.addEventListener("click", function () {
    pasteCatcher.focus();
  });
}
// Add the paste event listener
window.addEventListener("paste", pasteHandler);

/* Handle paste events */

function pasteHandler(e) {
  // We need to check if event.clipboardData is supported (Chrome)
  if (e.clipboardData && e.clipboardData.items) {
    // Get the items from the clipboard
    var items = e.clipboardData.items;
    if (items) {
      // Loop through all items, looking for any kind of image
      for (var i = 0; i < items.length; i++) {
        if (items[i].type.indexOf("image") !== -1) {
          // We need to represent the image as a file,
          var blob = items[i].getAsFile();
          // and use a URL or webkitURL (whichever is available to the browser)
          // to create a temporary URL to the object
          var URLObj = window.URL || window.webkitURL;
          var source = URLObj.createObjectURL(blob);

          // The URL can then be used as the source of an image
          createImage(source);
        }
      }
    }
    // If we can't handle clipboard data directly (Firefox), 
    // we need to read what was pasted from the contenteditable element
  } else {
    // This is a cheap trick to make sure we read the data
    // AFTER it has been inserted.
    setTimeout(checkInput, 1);
  }
}

/* Parse the input in the paste catcher element */

function checkInput() {
  // Store the pasted content in a variable
  Array.prototype.forEach(pasteCatcher.childNodes, function (a) {
    if (a) {
      // If the user pastes an image, the src attribute
      // will represent the image as a base64 encoded string.
      if (a.tagName === "IMG") {
        createImage(child.src);
      }
    }

  });

  // Clear the inner html to make sure we're always
  // getting the latest inserted content
  pasteCatcher.innerHTML = "";
}

/* Creates a new image from a given source */

function createImage(source) {
  var pastedImage = new Image();
  pastedImage.onload = function () {
    // You now have the image!
  }
  pastedImage.src = source;
  document.getElementsByTagName('body')[0].appendChild(pastedImage);
}