I want to push several hundred greyscale images through a threshold filter, so that an output pixel is black or white according to whether the corresponding input pixel is less or more than 1/2 bright. (My goal is a ‘woodcut’ effect.)

ImageMagick can apparently do this with one command, but I lack a library that it needs.

GIMP has a menu command with this function, but to do it from a script it seems I’d need to learn Scheme.

I could write a program using Python Imaging Library (which I’ve used to output most of my mathematical designs in recent years), but so far in RTFM I can’t tell how to, y’know, access the pixels it reads in. Later: Found a better FM.

Wish me luck.

In MacBSD, the command cal 9 1752 shows the shortening of that month in the British Empire. If I reinstall MacOS and choose Italian as its default language, will the shift show up instead in October 1582?

A look at 404s in my HTTP log revealed a bug in my math pix page, which in two places chooses randomly from families of images. I didn’t know that the PHP function rand(nmin,nmax) is inclusive at both ends.

When I answer the ’phone, I generally say either “Yes?” or “Good day/evening, Sherwoods” rather than “Hello.” With cold-callers I often don’t get a response to that; I pause and try a variation or two of “Is someone there?” before the caller speaks up with a bewildered “Hello?”.

Does their robo-dialer wait for a “Hello” before prompting the human that it has found a live line?

I had assumed that Pixar did not use ray-tracing because it could not provide certain desired lighting effects. Now Dad tells me that Monsters University is Pixar’s first ray-traced feature, which implies that the speed wasn’t available until now.

Hm, Shapeways has an API. If I were a skilled Web programmer I’d make a page where you can choose the size and frequencies of a Klein bagel model …

I miss the popup menu of recent pages in this tab, that was beside the back/forward buttons in Firefox 3.

The bar at the bottom of the window has gone away, to save space for content; status notices now appear in floaters over content, in the same place. I’m not in love with this behavior.