Substack has been glitching out on me this week, which is why you may have received multiple threads announcing David Britland’s new column. It’s also why you received an article last night when I tried to unscheduled it.

I was unscheduling it so I could send out this more topical article today instead — not ideal. I could wait a week, but I’m going to give you an extra article instead. I think this is worth letting paid subscribers know about as soon as possible.

Last night, two coders shared some fascinating new software. The complete source is free to use as well as detailed documentation on how anyone can get up and running with their software and system.

This deck of cards has a unique barcode printed on its side. Scanning the barcode will reveal where every card is within the deck (or isn’t — if cards are missing).

A camera scans the deck and feeds the data into software that can tell you whatever you like based on the information. I hope your minds are already going wild with possible applications.

A marked deck was released that used a similar principle many years ago. The marking was fast enough to be read by the human eye and would only tell you which card had been selected.

The brilliant thing about that release was that the marking used special invisible UV inks. Ah, it looks like these clever coders also thought of that.

One of these decks is unmarked, and the other has a unique barcode printed with invisible inks. The infrared ink is only visible under special infrared conditions.

While I think magicians could happily hide one edge of the deck, this significantly improves the magic. You can mark both sides of the deck with the same barcode, so you could easily hand the cards out for inspection and shuffling.

This small device is a Raspberry Pi Zero W with a NoIR camera. It can see the invisible markings on the card. See that shiny circle — that’s the special IR filter. A scanning server runs on this small device.