Haunted House

Here is a picture of a building in Amsterdam that we visited recently. My fiancé and I went to Amsterdam for the weekend and took this picture among many others, but this one looks as if something is coming out of one of the windows of the building. It looks to me very much like a genie although I'm sure that it could be explained normally. At the time it was taken, there were people sitting outside. Could it be smoke from their cigarettes? I would be very grateful if you could let me know what your opinion is of this picture and the strange image that is hovering at the top of it.