-{ a hewer of maps }-

Record internet radio with VLC, updated

I needed to record a CBC radio piece today. For most cases, it appears the easiest route is to use streamtuner and streamripper, however there is something about my particular computer or CBC’s streaming style that made it difficult for me. Since it took a couple of hours to figure it all out, I figured I’d better save it for future reference. So here is a vlc only method which works, but with more clicks and it’s is easier to select a combination of options that don’t work than do. This is the combination which finally worked for me:

What does your Map projection say about you?

Xkcd has a wonderful comic on map projections in common and not so common use, and what each of them have to say about the personalities of those who like them. A blog post and accompanying conversation at Explain XKCD fills out some of the jokes.

I liked so much I've reworked it into a 10"x12" mini-poster for printing:

Wanted: dead simple argparse examples

The standard documentation for the argparse python module, while excellent I'm sure, is too much for my tiny brain to grasp. I don't need to do math on the command line or meddle with formatting lines on the screen or change option characters. All I want to do is "if arg is A, do this, if B do that, if none of the above show help and quit"


I’ve been sporadically working on a little command line installer for OSGeo4W, called apt. It is based on cyg-apt, a command line apt-get-like installer for cygwin byJan Nieuwenhuizen. I currently have two forks. One for o4w alone, which I’ve renamed apt, and the second for cygwin alone, which I’ve left as cyg-apt. Forking is not a good idea when there is so much in common, so I’m going to try and bring them together. One app, two installers. Neither name fits this new job so I’m going to use appy for the time being. It will have to change eventually as there’s another, much bigger, python project with the appy name, but I continue.


v10 license file for Core

Mindtouch now consolidates all of it's products into a single set of packages, which is good, however this necessitates contacting HQ for a license file even for the open source Core version. Some are bothered by this and don't want to give Mindtouch Corp their email address. If you are in this group feel free to use the attached license file (rename to 'license.xml'). It is "licensed" to mindtouch-core@safetymail.info.

Downgrade from Enterprise to Core

As a result of this thread I periodically get private messages asking how to downgrade to the open source. It's really very simple (though I don't know if this is still true with v10):

hi maphew, we continue.

Police make it hard to report

Police make it hard to report things to them.

Last week while on a canoe trip we spotted a minivan crashed in the river, at the bottom of a 30m+ cliff. From the open driver's side door It looked like it had been pushed over the edge, and, judging from the multi-level water stains on the side, had been there for a week or two at least. Still, being good citizens when we got to somewhere we could make a call we phoned the police just in case nobody had reported it yet. They received the report easily enough but then demanded name, phone number, street address, a continue.

Pale Blue Dot

This article came across my desk and inspired me to make a poster. Well, it inspired me to find a poster, but I didn't locate one that resonated just the right way with me, so I made my own.

A portion of the first ever 'portrait' of the solar system taken by Voyager 1 in 1990 from a distance of more than 4 billion miles from Earth. Our world is a mere point of light, a crescent only 0.12 pixels in size, coincidentally right in the center of a scattered light ray, resulting from taking the image so close to the sun.

"We succeeded in taking that picture , continue.

Time Traveller Drop Points

I was cleaning out old email and ran across this important message which fell through the cracks. I don't have the time to fulfill this urgent request, but thought perhaps I could help by getting the word out to someone who can. Thus was born the Time Traveller drop points:

A web map service for Time Travellers who need to arrange for pick up and or delivery of specialty goods. On the go and need a supply dump provisioned? Put your drop point and request here.\ \ NOTE: payment and delivery term arrangements are *strictly* between traveller and deliverer. We don't want to know about it and will not continue.

Decollaring with nearblack

The attached geotiff image has two collars to be removed. The outermost consists of pure black (0,0,0) while the innermost is off-white (ranges from 240 thru 255). I used gdalsetnull to change 0,0,0 to nodata, then ran `nearblack -white` on the result. I detect no difference in the output image even with a very large fuzz factor (-near 50) .

What am I doing wrong?


From Even Rouault I learned that nearblack doesn't grok nodata, it just looks at the pixel values. Consequently it never sees the white collar, except a small portion at the very top of the image.

Thankfully Luke Pinner, who's come to my aid before, has an elegant solution using a VRT intermediate file (ref):


ipy and arcgisscripting

….some further experiments with ipythonand ArcGIS python geoprocessing. Here is a simple script to convert a bunch of coverages to shapefile. There are 9 coverages occupying 3mb, it takes about 6 minutes, consumes 2 processors to 80-90% capacity and chews through 300mb of ram:

cd w:/Env-dat.003/2007-March/workspace/envy_ed2import arcgisscripting
gp = arcgisscripting.create()
gp.Workspace =./todo = !dir /b fwtc*

for cov in todo:
      print cov
      gp.FeatureClassToShapefile( cov +/arc,./shp)
      print gp.GetMessages()

Contrast that to using fwtools ogr2ogr, which takes 10 seconds:

for %a in (fwtc*) do ogr2ogr -f “esri shapefile” ogr\%a %a

The problem is, ogr2ogr doesn’t continue.

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