Or when you want to insert your pet cat into a family photo you already took without him? No, you actually don't need to rush ...

We need the original picture to be behind the overlay so we’re making it a background image using the CSS property ‘background’. The PNG overlay is then set as the new SRC for the IMG element.

He then loaded the frame with random psychedelic pictures he found online, as well as some custom overlays which he quickly whipped up using colored blocks in an art program. In the video after ...