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cityscape

CN Tower’s Flashing Images, Unfolding Like a Film Strip

A visual effects compositor puts together the images the CN Tower elevators show in fragments.

Ever since the CN Tower installed LED lamps five years ago, Torontonians have been split on whether they love or hate the colourful displays coming from the tower. What many don’t realize is that sometimes, the lights aren’t just thematic (red and white for Canada Day, rainbow for Pride): on occasion they are made up of slivers of images as well, displayed in sequence so you see each little sliver by turn.

Confused? One local visual effects compositor, Avi Salem, makes it clearer in a video he made recently—by taking those slivers and putting them back together, reconstituting the images the CN Tower started with.

Salem explained more about his process to us by email:

Since [each image pans] across the elevator shaft revealing a sliver of itself, all I had to do was do the opposite. Using compositing software, I created a slit scan effect on the elevator shaft, and then overlaid it on the original footage.

In detail: I cut out the shaft from the footage and moved it across the screen over time at the same speed the image is scrolling. On top of this I applied an effect that will leave a trail of the shaft as it moved along. This left me with a long image. Finally, I moved the image in reversed, created a reveal in front of the tower, and overlaid it over the original footage.

(He also pointed out to us that iPhone users can do something similar with an app called Slit-Scan.)

Salem isn’t entirely happy with the results so far—he’s hoping to put together a longer version, in sharper focus—but the folks over at the CN Tower were pretty impressed when we showed it to them, and it’s certainly the most fun Toronto-themed video we’ve come across in quite some time.

[Hat tip to Matt Elliott.]

Comments

  • Anonymous

    HD webcam… get on it CN tower people… I totally want to see what pictures are flying through the air… best screen saver EVER.

  • Adam

    Wait, some people actually don’t like that they put LEDs up the CN Tower??

    That’s one of the best things they’ve done to it in 20 years.

    • http://twitter.com/wadexyz wadexyz

      yeah i agree with Adam, who’s “split” on this?

  • http://flavors.me/40deuce 40deuce

    Avi is my buddy. I didn’t believe him that there were pictures in the CN Tower until he started taking these pics. It’s pretty cool.

  • http://www.joshuahind.com/ Joshua Hind

    The process of displaying a video on a low resolution display, like one side of the CN Tower, is called pixel mapping, if you’re curious. It can also be used in more complex situations, like this: http://www.youtube.com/watch?v=qSQnsq_ZiKU