Jon Suen: Evil Incarnate

I hate to even post this, since it will only encourage him, but:

Jon Suen took a picture of three friends sitting on a bench, did some matlab magic on the photo to adjust the perspective, then calculated how much weight a friend had put on leading up to his marriage.

The full entry is worth a read, but here’s an excerpt for the lazy:

Everybody remembers Bobby from the Rock, the high school football jock everybody wanted to sleep with, paraphrasing somebody’s blog, and drew certain comparisons to a certain “Shane” (we’ll leave it at that, thank you). Well Blobby’s getting married, and apparently gained some weight.

Well, so did everybody else (but me, well, maybe 5 pounds). But did he really gain that much more weight? The deflection in the springs at the top of the bench make a perfect benchmark. But wait! The image is taken off-center, so the closer spring will look longer. No problem, I took ECE 181B Computer Vision, the perspective transformation is simply a homotropic map. If I have four points in the corresponding image, we can solve for the 4-DOF transform matrix. We’ll just dig out our first homework assignment, which uses eight points and a least-squares fit for better accuracy, and run it in Matlab. All I need to do is select eight points in perspective, and place where i want those eight points in a linear view, and…

[redacted]

So we have that, and now we make calculations. We know that Onklar weighs about 160 pounds, Samit 180 pounds. We assume Onkar is sitting in the middle, so he adds 80 pounds to both sides. So Samit’s side weighs 260 pounds. If we assume we are in the standard deflection range of the springs, we can say they are linear devices. Therefore, the left spring is 11.76% longer than the right spring, or Blob’s side weighs the same amount more. Therefore, the left side of the bench weighs in at 306 pounds. Subtract Onklar’s 80 pounds, and we conclude that Bobby weighs 226 pounds.