Applying an Inverted Effect to Tiles
First of all I opened the original image in PhotoShop.
I then inverted the image by going to Image > Adjustments > Invert.
I created a new layer and used the Rectangular Selection Tool and drew out an area which covered the tiles in the top left-hand corner. This was filled with white.
I finished off the design by applying a small piece of text 'lens flare ants' which was a dark-grey (999999). I then moved this layer above the rectangular white box layer.
This is the final result:
