After last week’s discussion about the relative merits of paper and electronic storage for text and photos, I was particularly intrigued to come across a blog post about paper as a backup medium. Someone has actually gone and invented a program that will back your data up in the form of zillions of squares of tiny black dots (90,000 per square inch of paper at 300 DPI). You can get all of about 5 KB of uncompressed data on a page if you’ve got a 600 DPI laser printer. (Inkjets don’t work as well for this.) To restore data, you need a high-resolution scanner.
Now, I can remember when a Mac’s entire operating system ran on a 4 KB diskette. And I’m sure some of you remember the days when computers were the size of a building and ran on punch cards or punch tape. But given the size of even a short Microsoft Word document these days (last week’s Backup Reminder is 57 KB), you’d be well advised just to print the file, then scan it into an Optical Character Recognition program.
So you won’t be too surprised that this program, PaperBack, was created as “an open-source joke.” But it’s a real program, and Karl Gechlik over at Ask the Admin went and tested it. He backed up a 13.7 MB program called PC Tools AntiVirus Free Edition to an 88-page, 100 MB PDF file. Is there an antonym for “data compression”?
I passed this link along to the Ur-Guru with the comment “Now that is weird.” His response (as so often) made me feel slightly foolish:
No it’s not, actually.
Do you remember how my exit-slip looked, the one I got not the last time but the one before, when I left the US? That paper thing with all those weird dots like a mashed up barcode in blocks? Same thing.
Various of those things have been used to store data as “print,” so extending it to full sheets makes sense.
Sure enough, as soon as he mentioned his travel documents, I realized that I’d seen something similar when printing my own Southwest boarding passes. (You can do a Google image search for “print boarding pass” if you’ve never seen one.)
But the next comment really surprised me:
I once wrote a tool that did something similar, trying to compress actual data into color bitmap images. The idea was to print in color and scan them back in as a backup but scanners and color reproduction was not good enough [in 1997] for the full 0-255 range of integers and as a result it wasn’t viable or practical for large amounts of data.
It was, however, very viable at 0-32 ranges of color (RGB per pixel or dot printed at up to 600 dpi) as a means of encryption and to travel with data that would not appear to be data. 🙂
I’ve talked about encrypting backups occasionally, but I’ve never thought about attempting to disguise my data as something other than data. Though I will say that if I were a customs inspector and someone had a heavy suitcase full of paper printed all over with tiny black dots, I’d start to suspect that something funny was going on.
If you have a funny story about backup—or a tragic one—and would like to write a guest column for this newsletter, just e-mail me.