Well, you can download the image, open it, parse the colours and load it in your engine
It's png, so no compression artefacts.
Doors : (255,0,0)
Rooms : (0,255,255)
corridors : (255,255,0)
Entry/Exit : (0,0,255)
Rest colours are walls
The entry and exit points have been set so that the 'room distance' (number of doors that you need to pass through) between them is the largest 'room distance' that you can get in the dungeon.