Filtered for calibration

14.39, Friday 17 Sep 2021


Hello, World!

From the Jargon File: Traditionally, the first program a C coder is supposed to write in a new environment is one that just prints “hello, world” to standard output.

C is an ancient language. The first documented appearance of “Hello, World!” is in the 1972 training manual for C’s predecessor language B, written by Brian Kernighan (source).

I use it, whenever I’m writing a new program in any language. Perhaps you do too. It’s half habit, half being connected with the lineage, and half a proof that everything deeper in the stack is working as expected… the terminal is outputting text so I can see it; the language interpreter was compiled properly; the OS has enough memory; the electrons are still doing their electronic thing – all these things have to be tested once, they can’t be assumed.


Ich bin ein Paradigm Shifter, Karlheinz Brandenburg, the inventor of the MP3 and his muse: Suzanne Vega.

MP3 is remarkable not just because it makes music into a very small digital file format, but because that file format was the lynchpin of an entire industry. Files can be played, bought, and sold. A multiplayer economy! The power of the file!

To create MP3, Brandenburg had to appreciate how the human ear perceives sound.

He heard Suzanne Vega’s wonderful acappella song Tom’s Diner playing down a corridor and adopted it.

Because the song depends on very subtle nuances of Vega’s inflection, the algorithm would have to be very, very good to select the most important parts of the sound file and discard the rest. So Brandenburg tested each refinement of his system with “Tom’s Diner.” He wound up listening to the song thousands of times, and the result was a code that was heard around the world. When an MP3 player compresses music by anyone from Courtney Love to Kenny G, it is replicating the way that Brandenburg heard Suzanne Vega.


In 1974, Martin Newell made important contributions to the rendering of 3D graphics as part of his PhD at the University of Utah.

But he needed a sufficiently complex object for his demos.

One day over tea, Newell told his wife Sandra that he needed more interesting models. Sandra suggested that he digitize the shapes of the tea service they were using, a simple Melitta set from a local department store. It was an auspicious choice: The curves, handle, lid, and spout of the teapot all conspired to make it an ideal object for graphical experiment. Unlike other objects, the teapot could, for instance, cast a shadow on itself in several places. Newell grabbed some graph paper and a pencil, and sketched it.

The Utah teapot.

These days, the Utah teapot has achieved legendary status. It’s a built-in shape in many 3D graphics software packages used for testing, benchmarking, and demonstration. Graphics geeks like to sneak it into scenes and games as an in-joke, an homage to their countless hours of rendering teapots; hence its appearances in Windows, Toy Story, and The Simpsons.

The traditional test that you run through the pipeline to check everything’s working. I guess every specialism has something like this – testing, testing, 1, 2, 1, 2. I wonder if they have a generic name. It would be fun to collect them.


The Forgotten ‘China Girls’ Hidden at the Beginning of Old Films (Atlas Obscura): Used as quality control, these haunting images were never meant to be public.

Faces of people (typically women, almost always white) at the beginning of a film reel, to help the projectionist check that everything is functioning as expected.

The image carries bias with it. Colour film was terrible at depicting people of colour for years and years and years, with the issue being addressed only in the 1970s in response to advertisers: wood furniture and chocolate makers began complaining that Kodak film wasn’t capturing the difference in wood grains and chocolate types. Shocking.


Beagle 2 was the ESA lander dispatched to the surface of Mars in 2003… and lost. Cameras on landers have calibration images for colour correction etc, checking against a known image, and Beagle 2 used a custom Damien Hirst spot painting.

Here it is: “Beagle 2 Calibration Target”, 2002, natural pigments on aluminium, .35 x 3 x 3 in.

When we get people to Mars, if we settle the surface, they should go to where the lander was eventually found (it was found by satellite in 2015) and build a gallery around it. Leave the art in situ.

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