June 2003

Hello friends,

Last month I went to a vision students' workshop at McGill University, in Montreal. Students from four universities attended the workshop, and gave about 25 presentations on their research. Highlights of the workshop: A group in the University of Montreal is applying computer vision to orthodontics. They 3D-scan teeth, use computer graphics to visualize teeth in three dimensions, and give the orthodontist a simulation tool for applying forces so that the teeth will clutch exactly (this is still experimental). A professor from McGill invented optical-snow. This model differs from optical-flow in the assumption that particles in the scene move like falling snow (constant speed and parallel). To solve the model he takes the Fourier transform of the falling snow. You in Israel could be the first to invent optical fata-morgana…

I also had time to tour the city. After Paris, Montreal is the second largest French speaking city in the world. It is the new-world capital of the francophone world. Many immigrants arrived there from Africa and North-Africa (did you know that out of three million Lebanese 100,000 live in Montreal?). There are also students from France that study in Montreal. The French people in Montreal also speak English. In fact, when people in Toronto think I am French because of my English, I get it as a compliment. The people there preserve their French heritage. For instance, they teach their children eighteen-century folk songs that have long been forgotten in France. A derivative from the French culture is that Montreal has some unexpected, little, differences. Ambulances in Montreal are colored yellow, and fire trucks are green. They have there east-west streets that run north-south (They say it is because the river makes a turn. In Toronto, the people will shoot the mayor for such disorder). Another surprise: not all water taps in Montreal open clockwise. At least they use the metric system. Pedestrians in Montreal cross roads in red light (I am speaking about six-lane roads). Given that they drive like in France, it is very dangerous, but surprisingly the accidents rate is lower than in Toronto (partly because you can turn right on red light in Toronto). In terms of the architecture, Montreal is very European. Going to Montreal is like crossing a time tunnel back to the seventies. It reminds the concrete style that was used in Israel these years. They tried to be modern and after 40 years their buildings look out of date.

Speaking about modernity, while we were at McGill there was an international conference on new interfaces for musical expression at the music department. We went to two concerts, which were described by one student as "the weirdest thing I have ever heard". They had all stuff of computerized musical instruments. For example, to play one instrument the player waves hands. A sensor detects these movements and the computer transforms the movements to music (or noise). They also played a piece over a fast internet connection. One group of players was on the stage, while the other was at Princeton University. They used cameras and screens for the players to see each other. This could be the future of chamber music. We were also lucky to be in Montreal on their Museums day. On this annual day, there is free entrance to museums of art, history and science. This is an attempt to expose the arts to the general public, and also an attraction for tourists. Since they have about 30 museums, the crowd was tolerable.

When I came back from Montreal, I did a course project analyzing a dice game called "Yaht" (known also as "Yahtzee"). It was popular in the late Eighties. Those of you who practice their probabilistic instincts regularly would be pleased to hear that at least the single-player game can be solved to optimality. On average, the score of the old DOS program is just about 80% of the optimum. How many of you know this game?


Ady.