Monthly Archives: November 2005

Spyware In Multimedia Files

I am a big fan of Rooster Teeth’s Red vs. Blue Machinima series– in fact, I own all 3 of the DVDs so far. I was excited to see that Rooster Teeth was commissioned to create a Machinima mini-series for the new F.E.A.R. game called P.A.N.I.C.S.

P.A.N.I.C.S. Title

Funny stuff. Download and enjoy. But to be safe, use an open source multimedia playback application. Here is a curious excerpt from the P.A.N.I.C.S. FAQ:

Q: When I play the video my firewall says it’s trying to access the internet, what’s the deal?
A: The producers and promotions company wanted to track the popularity of the videos, so they added a small tag that hits a server, much like a webpage counter. No information besides the IP and the hit are recorded.

I have been trying to figure out if the tracking mechanism is embedded in the multimedia files somehow. My hypothesis is that there is some kind of information embedded in the multimedia files that instructs the multimedia player to perform an HTTP GET request to a web server. Each of the 4 downloadable files is available in both Windows Media and QuickTime formats. I know that QuickTime is hyper-flexible enough to allow for arbitrary things like requesting web pages; it’s reasonable that WMV supports a similar feature. However, looking through the files with a hex editor reveals no obvious “http://…” strings, even when I decompress the QuickTime header in the .mov files.

If anyone knows how this tracking tech operates, I’m sure I’m not the only interested party.

The moral of the story is to always use open source software to view your multimedia. You can trust that the open source multimedia players do not implement user-surveillance features because we developers do not even know how the features work!

Believe it or not, security is a high priority among open source multimedia hackers. For example, on the FFmpeg project, the decree is in place that no file creation facilities (like file muxers) may place valid timestamp data into the file which would indicate when the file was created. It was believed among some that this is tantamount to spyware. If you have trouble swallowing that reasoning, a less tinfoil-hat-like explanation is that arbitrary timestamps create havoc with regression testing.

I just thought you might like to know that we’re looking out for you and your safe computing experience.

Free Games That Used To Be Commercial Games

As I read new trivia additions on MobyGames, I see more and more bits about commercial games being open sourced. I figured that there must be some site out there that documents such transitions and lo and behold:

I wager there is some custom FMV code in there somewhere. We already know for a fact that:

  • Descent II source contains a 16-bit Interplay MVE decoder
  • Quake II source contains a Quake II Cinematic (.cin) decoder
  • Quake III source contains a RoQ decoder

A number of the games listed at Liberated Games are only free in that the binary executable and data are available, but no source code.

A few more items I would like to investigate:

Update: Trixter sends this intelligence about the titles above:

  • Hexen II — can’t verify if that’s video, but there are Animation credits in the game so it is probably yes. However, most times that stuff is a FLIC file. (BTW, don’t get all bunched up over FLIC — there are two main variants that are easy to support; the rest of all that junk was introduced and supported by only that one company you found the info on.)
  • Stargunner: same thing, most likely a 320×200 VGA FLIC.
  • H&D: no video as far as I know.

Microsoft Video-1 Based on DCT?

I recently learned that Wikipedia has an entry for Microsoft Video-1. The entry makes two assertions of which I was heretofore unaware:

  1. the codec was licensed from Media Vision and is based on a codec called MotiVE
  2. the codec was based on the discrete cosine transform (DCT)

I can accept assertion #1 but I have trouble with the second. I just don’t see it. Per my understanding Video-1 falls into the category of vector quantizer. I did a quick Google search for “media vision motive cosine” to search for supporting details. This page supports the DCT claim. But it also claims that Duck TrueMotion 1 is a vector quantizer (nope). Here is another page that mentions the MotiVE connection but pegs Video-1 as a vector quantizer.

At least the Wikipedia article links to my Video-1 description so interested parties can investigate the details for themselves.