Thursday
Mar142013

Yellowstone at play part 2

I've made some improvements to the seismogram to sonogram notebook.  will post soon. 

Basically, I improved the sonogram digitizer.  I also I did a wavelet transform to change time isolated events into a frequency table.   The time-frequency tables adds noise that looks something like a numerical moire pattern, but it also appears to be moderately predictive over a short period (perhaps as much as 40 minutes).  

Not really happy with Mathematica's wavelet transforms - seismic  waves are often asymmetric - they spike and then fade |\~-, Gabor wavelets or Mexican hat wavelets and the like -~/|\~- build, spike and then fall off.    I think in some fundamental way I don't quite understand wavelet mathematics or why the implementation is done the way it is.  Implementation seem unusually inflexible, specific and idiosyncratic...  Almost like the science was documented by a unwilling telecomm committee disclosure through a party of moderately baffled lawyers rather than directly from the coherent words, insight and teachings of a brilliant mind.  

 The first go was really just for fun and cranked out after the kids went to be one night.  When I figure out how to better put a good shine on my wavelets,  I'll repost.

Thursday
Feb212013

The Sounds of Yellowstone

I rather like Yellowstone National Park... fantastic place... well, except for the bear that most regretably attacked and killed Marylyn Matayoshi's husband during my family's first visit.  Still, the park is a beautiful wonder, a special and extraordinary not-exactly-dormant volcano graced with an abundance of life, and perhaps too, an abundance of death. 

In honor of this park, I have something fun to share - and a little bit of code that converts yellowstone webcast heliocorder seismograms into a breif audio clip.  Nothing like the ears when it comes to signal processing, the brain and ears can even out perform a fourier analysis at signal detection.  


My webcorder seismogram to sonogram/sound
  

(Graphic above: I'm not versed in Java, so that graphic don't sing w/click.)

Here's a rough mathematica notebook that that takes a black/red/blue/green plot heliocorder seismogram and converts it to audio by crunching 24 hours of playback into a minute.   This is my own code, offered freely with the expectation that anyone using my poorly implemented idea to make a drastically improved derivative work will still polietly cite my imperfect original as a great motivator to do better. 

This http://www.isthisthingon.org/Yellowstone/daythumbs.php website has well organized seismogram pictures of the yellowstone region, and if you have mathematica 9 you can pop those pictures into the notebook.  

This is a mathematica notebook file - you probably can't do much with it unless you have mathematica 9:  yellowsound.nb  (yep, that choice limits my potential audience by a factor of 1 in every 94,936.71 visitors or so.)

If don't have mathematica, but want to see the code and run the computable document format version, click here:  yellow  Click play at the very bottom, this code should run as long as you have www.Wolfram.com's computable document format reader installed in your web browser.  The math CDF player is free and runs on a number of OS and browsers.  

Helicorder data image: Feb 20, 2012 from Mammoth Vault Yellowstone National Park.

Sound output after cranking the hurdy-gurdy code:  Sound_1  (download and play)  Note: I had to download before play on Chrome, but not in Safari. 

And Here's a more typical yellowstone sound from an somewhat active chart at YMR Madision River Yellowstone Park Feb 20, 2013:

Sound 2 (download and play, or just image what standing next to a large slowly roiling lava lake might sound like.)

Notes to the ambitious:  I'm personally impressed with what this thing does in 26? lines of code, but the 'frames' for each seismic line don't stay centered through each 15min reading frame line.  Highly active charts overlap, and this code will not discriminate overlap bleed through from from real signal.  Raw data really is the right place to start with a seismo-audio-gram, not from a pre-generated chart.   

Sunday
Feb172013

The Exotic Fruit Hunters

Here is something intresting:  

http://www.variety.com/article/VR1118066014/

Sounds like a perfect social-botany-documentary for me.  I look forward to seeing it.

I'm growing a few asian pears.  I grew up amongst wild asparagus, ate tender young ferns bracks, and fresh green spring nettles.  We had easy wild red raspberries but prefered to hunt fantastic wild blueberries the season after fire razed a section of forest, or blackcaps and yellowcaps as well as the formitable thorny blackberry (where a wrong move would rip your sleves to shreds.)

I've wanted to plant a medlar tree just to try a christmas recipe that calls for it from the 18th century.  Medlar is a kind of an open-arse wood-hard apple relative that pretty much has to be fermented to soften it enough for consumption.  Maybe not delicious, but I suspect it would make quite a unique hard cider.

 

July 2014- Saw the movie a few months ago and enjoyed.   Great watch for gardeners.  Now if only there was a documentry about high-alpine dense wildflower lawns.  I really like the 6" tall, walking on flowers - fairy lawn look... green grass is so 1900's.  

Sunday
Feb172013

Jonathan Coulton ripped by Glee?

I rather like a couple of JC's songs.  Can't count myself a loyal fan, but it comes as a disappointment to me that he's had trouble with FOX.  After getting the rights to "Baby Got Back" by Sir Mix a Lot, he created an seemingly entirely new arrangement and melody that sounds tender, is about awkward self realizations and is humerously lovestruck.  The original's style seems squarely aimed at loud obnoxious objectification with a good humpy beat. 

His problem comes from FOX's Glee show having purchased the rights to "Baby Got Back" from Sir Mix a Lot's label, and then having used JC's novel arrangement without any compensation or credit.  His legal recourse seems limited.

So what is a man like JC to do?   Apparently a twitter campaign.

What's done is done, but a musician might avoid future similar situations by releasing a wholly self-owned instrumental version before releasing a lyrics-only cover.  This might bifurcate the ownership rights a bit more clearly.  

Karaoke fun, anyone?

Wednesday
Jan302013

Aquatic laser array - satellite based mobile listening outposts

Interesting link here:  http://www.atimes.com/atimes/China/LE13Ad01.html

it appears that a laser distance scanner mounted on a satilite can scan a block of ocean, report acurate ocean wavelet heights and work out the locations of every big fish in the sea... or act as a point-it-anywhere submarine hydrophone.

Pretty easy for me to see how such a device could make a mobile listening outpost... it's trivial to beam a laser it at a window and route reflected antenna (sensor) signal to a mic.  I could do that much back in high school.  But building a underwater radar picture from a wavelet map seems... well at the very least tedious.  Maybe a deconvolution matrix mixed with a fourier transform would make it possible?  Probably would want long wavelength - far infrared - so that it could zip through clouds.  

 Random daily thoughts.  Maybe I can get one of my kids to work on this idea for a science fair.  Proof of concept with optical laser would probably work.