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Calling to Isolated Sets

At some contra dances the sets start to take on characteristics. There might be a set all the experienced dancers want to be in, or a set with the younger dancers. Divisions like this are probably not good for a dance community (though I'm not totally sure) but there are some times when they're just too much.

The key question is why are people are isolating themselves in certain sets instead of dancing in the whole hall? I think the main reason is usually wanting to dance with friends as opposed to trying to avoid people. Which means anything you try to fix this needs to let people keep dancing with their friends.

Which shows why this is pretty hard for individual dancers to fix. more...

Produce Lyme Vaccine?

Lyme disease is pretty bad. Many of my friends have had it, ranging from something that was rough for a while but got better all they way out to several who now have a major chronic illness on their hands. Most of these people I know through dancing, and when a lot of your social life is built around a physical activity it's especially bad to lose it. [1]

What really gets me, though, is there's a vaccine. It was approved by the FDA as safe and effective, and it was on the market from 1998 to 2002. There were some people who reported side-effects from the vaccine, but the FDA looked into these reports (doc, pdf) and determined there wasn't reason to believe the vaccine was causing these problems. Still, there was a large media storm, people stopped asking for the vaccine, and its manufacturers stopped making it.

What would it take to get someone to make this vaccine again? more...

Page for icdiff

A while ago I wrote a program to make two-column highlighted diffs on the command line:

I find it really useful, but many people who I think would feel similarly don't know about it. So I just made a small page describing it with screenshots etc: www.jefftk.com/icdiff. more...

Ambient Bus Times

My commute home consists of a subway and a bus. The subway is frequent enough that I don't worry about it, but the bus runs every 20 minutes at best, sometimes longer. Plus there are sometimes delays, and it's good to know about these before I leave work. I can check the online bus predictions, but this takes some overhead. What if I could have an ambient reminder of this?

I made a little script that pulls down the realtime predictions for when my bus will leave the station, parses out the "minutes" field, color codes it by whether I probably have time to catch it, and prints it to my terminal. I leave it running on a terminal in the corner of my desktop and it looks like:
Thursday 2014-12-04 06:06 pm   23   29   47   70   90 more...

WebP Quality Settings

One of the questions that came out of the UA-parsing discussion was whether pagespeed compresses WebPs too agressively. In general PageSpeed tries to compress images to the lowest quality that will still look good enough, because then they'll use as little bandwidth as possible and load faster. By default it's sense of "good enough quality" for JPEG is 85, and for WebP it's 80, [1] but are these equivalent?

For a test set I took the 668 full size JPEGs under jefftk.com/pictures that had a quality of at least 85. [2] I compressed them all as both JPEG and WebP at qualities 45, 50, 55, 60, 65, 70, 75, 80, and 85. To measure the image quality I used SSIM with SSIM.cpp. Here's a graph of quality against SSIM for WebP and JPEG, higher SSIM being better:

It looks like WebP at 80 is equivalent to JPEG at ~67, not JPEG at 85. Maybe there's something suspect with this SSIM implementation? more...

Compiling SSIM on Mac

If you want to examine the distortion that comes from a lossy compression algorithm, it's helpful to have a tool that's a good proxy for asking a person "how similar are these two images"? The standard algorithm for this is SSIM, but there are several implementations. I was initially using Pornel's dssim, but I wanted to compare this to Mehdi's SSIM. Mehdi's doesn't document how to compile it on a mac, so here's what worked for me: more...

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