I was looking for a release date for Half-Life 2: Episode Two on Valve’s official Orange Box site, and noticed some odd text to the left of the navigation bar. I’ve counter-rotated it below:

• PC-DVD FORMAT [symbol] [numbers] [symbol]
• A VALVE MULTI-PACK OFFERING
• LEFT TO OPEN, TURN FORWARD
• DISTRIBUTED IN THE U.S.A.
• WWW.VALVESOFTWARE.COM

I’d be interested to see what the numbers are in the first bullet, if they’re at all significant, but I’m most intrigued by this “left to open, turn forward” bit. Is there some significance to it, or is it just random text meant to fill up whitespace?

(Note that this isn’t the first time I’ve been able to partially decipher text in low-resolution images. I have some more examples from Half-Life 1 textures that I’ll put online again some time.)

Brute-force OCR

When reading the numbers in the first bullet, I came up with a string of digits that I was more or less confident with. As I looked longer, however, I began to second guess myself, until I could only read the zeros with any certainty. But I wonder, would software be able to do a better job?

The characters in the above image are 4 pixels tall — far too tiny for any OCR package to read reliably. That said, we don’t need to “read” them at all — I’m fairly certain already that the adjacent characters are numerals, so I can simply generate every two-digit number, rasterize them in the same font and size, and compare the images. However, as I cannot identify the font or the anti-aliasing algorithm used, this remains impractical.

I think this is the same as Dheera Venkatraman’s algorithm for deobfuscating mosaicked sensitive information.

This entry was posted Tuesday, September 25th, 2007 at 10:36 pm and is filed under Secrets. You can leave a response, or trackback from your own site.