Oxalis leaf-opening time-lapse

March 23rd, 2018

I decided to take a time lapse video of my Oxalis plant's leaves unfurling in the morning. This was a good decision! Let's see if the video (30 MB) shows up properly here:

If you have a big monitor, I recommend full-screening. It's 1920x1080 pixels.

This is probably Oxalis triangularis; the seeds or roots happened to be present in the dirt I was using to pot up another plant. The leaves perform this unfurling every morning (I think triggered by both light and schedule) and then close back up after the lights are out. The flash of light you see in the beginning of the video is me turning on the lights and opening the curtains. There's a delay before the plant responds, and after all the leaves are open you can see some of the stalks jockeying around to get a sunnier spot. Plants are doing this sort of movement all the time. It's hard to notice because of the timescales.

I had meant to take a series of time lapse photos, but accidentally took a 2 hour 18 minute video. The following was supposed to speed up the video by 400x, but instead is about 160x. I don't really know how to adjust frame dropping in ffmpeg, so I just fiddled until I got something I liked:


# The video was in 2 GB chunks in the `raw/` subdirectory, so I first had to
# put the filenames in order, then make a "join-file" for concatenation:
ls -1 raw | sed 's/^/file raw\//' > join.txt
# The audio was pointless noise, so I stripped it out:
ffmpeg -f concat -i join.txt -c copy -an joined-quiet.mp4
# Time lapse, with incorrect output filename:
ffmpeg -r:v 4800/1 -i joined-quiet.mp4 -r:v 12/1 sped-up-400x.mp4

What I ended up with is a 30 MB H264 video, 1920x1080 (pretty big). I could have smashed it down farther (got it down to 10 MB in one trial with HEVC), but I don't know much about browser support for various video formats, so I left it alone. Much better than the 16 GB source video in any event!

Router anti-recommendation: Asus RT-AC68U

February 24th, 2018

I bought an Asus RT-AC68U this weekend and tried to set it up. I was excited at first -- some aspects of the router are refreshingly better than the competition -- but ultimately I found it unusable problematic.

Updated after discovering a combination of misconfiguration and ISP shenanigans. My apologies to Asus, although there are still some serious issues with this router.

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Learning a language on tape: An inverse “memory palace” effect

January 27th, 2018

I've been learning Spanish with free lesson "tapes" from Language Transfer (which I highly recommend.) The lessons are a collection of short audio MP3s and take the format of conversations between a teacher and a student; he introduces the language a bit at a time, and asks her questions; the listener is supposed to pause the track and answer each question, then hit play and hear her answer (which is sometimes wrong, of course.) It's a great format, but the only time I listen to the tapes is when I am walking somewhere. And this has produced an interesting effect.

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Identity and findability on the web—some personal-historical notes

November 25th, 2017

A little meditation on how it has changed for me to be a person on the web.

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Proposal: Default scheme-less URLs to HTTPS

October 27th, 2017

It's 2017. Most sites that I visit now support HTTPS, and even redirect to it from insecure HTTP. What does this change? I have one suggestion: Software that autolinks bare domain names as URLs should default to https:// instead of http://.

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