Monthly Archives: March 2009

FATE on Twitter?

For the most part, I haven’t been able to abide the notion of Twitter, where people “micro-blog” little messages of up to 140 characters each. It just seems like a bunch of “look at me” nonsense with no real purpose. But then, I used to think the same about blogs in general until I found a few interesting blogs. Lately, I have finally found a few interesting people to follow on Twitter.


Twitter logo

Then I read mentions of “Twitter clients” and quickly realized that there is an entire software ecosystem around these little messages. Indeed, there is an officially sanctioned HTTP/REST-based API for writing your own client apps.

Naturally, where I’m going with this is: Would it be useful to adapt FATE to post, ahem, “tweets” regarding state transitions (something either broke or got fixed with an individual build)? Would anyone care, i.e., does anyone already actively follow Twitter? I’m getting close to the point where I believe I can implement an email notification system, most likely to a separate mailing list. But this new channel might not be too difficult to implement at the same time. (Actually, I’m still trying to figure out from the documentation whether or not it’s possible to post a new message through the API; I can’t find the right function, or perhaps I just don’t understand all the Twitter-specific jargon yet.)

This is a little more outlandish, but as I was looking at a list of tweets today, I suddenly wondered about the possibility of sending encrypted messages through such a channel. I’m not the only person who was curious. This person beat me to the brainstorm, even going so far as to hack up a proof of concept that encodes a message of arbitrary length into multiple tweets.

Reverse Engineering Math Formulas

Even though I have been studying and working on multimedia technology since 2000 — reverse engineering, documenting, and reimplementing a variety of audio and video codecs — I didn’t actually begin to understand why various algorithms achieved their compression until about 2003. I’m just like that — I study the practice first, and then the underlying theory eventually becomes clear to me (maybe; it has been 9 years and I still couldn’t explain everything about the discrete cosine transform if you asked).

I happened to be looking back over the ZMBV (DOSBox) video codec today. Continue reading

The Standard, Like It Or Not

I have been studying multimedia technology since 2000. It has been a pretty chaotic technological landscape. People who wanted to publish video on the web wondered what format to use (and occasionally sought my advice). Various fiefdoms arose around Microsoft, Apple, and Real, all hoping to claim the mantle of the standard web video format. Somewhere along the line, Macromedia “accidentally” established a standard web video format via the Flash Player (now Adobe’s).

A few years ago, Adobe (my employer, BTW) upgraded the video support in Flash Player to use the same video format that happened to sit at the top of QuickTime’s codec heap: QT-MP4/H.264/AAC. A few days ago, Microsoft announced the beta of Silverlight 3, which contains support for the same formats. After absorbing that information, it took a few days for the next thought to coalesce in my mind:

We have a standard multimedia format.

All the big players support the same multimedia stack (I think even Real Player supports the same stack). I know that’s dismaying to certain elements of the free software community who insist that Xiph’s multimedia stack is the “standard” (really! there are blessed RFCs to back it up and everything); you may not like it, but that’s the way it is:

  • QT-MP4 is the standard container format, not Ogg
  • H.264 is the standard video codec, not Theora (or dirac)
  • AAC (and also MP3, for historical purposes) is the standard audio codec, not Vorbis

Sure, you may, in principal, have to send a dollar or 2 over to the Patent Illuminati (though highly unlikely). But it’s either that, or, you know, not have a standard video format. (And remember, the HTML5 video tag is not coming to save you.)

At least the free software enthusiast can take comfort in knowing that open source (L/GPL) efforts such as FFmpeg and x264 aim to create the very best tools that anyone can possibly use to create these formats.

Addendum: Now that I think about it, I don’t necessarily know if Silverlight 3 will transport H.264 and AAC inside of a QT-MP4 container or somehow pack it into an ASF file. That would be interesting to find out, though I have read (possibly uninformed) blog chatter excited about being able to stream the same file through Flash and Silverlight.

GSoC 2009 is Afoot

FFmpeg has been accepted as a mentoring organization in the Google Summer of Code 2009 program. This is the program’s 5th year and FFmpeg’s 4th year in the program. Thanks as always to the big ‘G’.

To refresh, the GSoC pays students $4500 for a summer’s worth of work on qualified open source projects. FFmpeg is one of those projects. FFmpeg team members mentor various multimedia-related projects. Our current project proposals are listed in the wiki. And, as with the previous 2 years, we have some stringent requirements for our students– namely, a student must complete a small FFmpeg task, refining the solution based on critical feedback until it is part of the mainline codebase.

I personally haven’t committed to any mentor possibilities. I wonder if I should propose the Theora encoder again, which didn’t quite pan out last year? The thing is practically written already in my mind.