If you look at the footage at 00:28 you'll see a guy walking by with a bike. Check out the shadow of the guy. The projector was about 8-10 Ft off the ground or maybe on a top of a van. The location was almost on the left side of the building and the camera taking the video on the right side of it. (This was observed by the shadows)

Just watch the video and you can make your own judgement as where things are setup:) The only thing I don't know is the power of the projection.

It was very clever how it's done.

EDIT:
Also look at 3:09 as a streetcar passing by. Stop the video and look at the lowestportion of the projection on it. It has to be 3 meters or so (9Ft)
Well, I could be off a bit, due to optical and camera angles....

maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=rose+chong&sll=-37.814251,144.963169&sspn=0.098319,0.15295&ie=UTF8&ll=-37.806336,144.9818&spn=0,359.84705&t=h&z=13&layer=c&cbll=-37.806243,144.981816&panoid=pIqmFrTuwueptn-lddtQ4w&cbp=12,141.63,,0,-8.8

projector was positioned in second story window with the air conditioner to the right in rose chongs.