title: Add transparent space around a UIImage
body: <p>Lets say we have an image of 600X400 pixel and we want to end up with an new image of 1000x1000 pixel which contains the initial image in the centre and transparent space around it. How can I achieve that in code?</p>
  <p><img src="https://i.stack.imgur.com/7ctOu.png" alt="enter image description here" /></p>