Monthly Archives: November 2007

MDEC Comeback

I just wanted to draw attention to a recent effort by one Michael Sabin who has been building a Java application called jPSXdec to play back videos ripped from the Sony PlayStation 1.

Sony PlayStation

To review, the original PlayStation had a bit of dedicated hardware called the motion decoder (MDEC) which decoded specially formatted blocks of what were essentially motion JPEG data. Assorted games also compressed the blocks using Huffman codes which were decoded by software. While the MDEC hardware was rigid in the data it would accept, PS programmers could deploy whatever Huffman tables they chose. I always thought it would be an interesting project (and a natural extension of my usual efforts) to catalog the various tables needed to play movies from different games, as well as different strategies that games have used to store the data on the disc.

Michael S. has been doing just that. There is a blog to document jPSXdec’s progress. Near and dear to my heart, however, is the fact that he is building a remarkable document (seen in the project’s download list) that explains precisely how to decode this data, from the perspective of a non-multimedia geek, no less.


Google announced their Highly Open Participation Contest today. I really hope that the name is not a backronym inspired by the common acronym for International House of Pancakes. GHOP is an effort to bring pre-university students into the open source fold through a Summer of Code-like program. Whereas GSoC projects were required to center around code, these GHOP efforts can be related to documentation, QA, R&D, translation, and assorted other areas, as specified by participating project’s issue trackers.

Google Highly Open Participation Contest Logo

10 open source projects were selected for this initial run. FFmpeg was not one of them. According to the FAQ page, “each project has a fairly low barrier to entry”. I admit, that would eliminate FFmpeg from consideration right away.

YouTube’s Lucky Number

The number is 240. In learning how YouTube works its magic so that MobyGames may one day take user’s video submissions, Trixter has been doing his own poking at the video giant to determine what parameters the site uses to transcode user videos. What he learned: 240 lines, 240 kbps, 240 frames in a GOP. His best guess for why things are the way the are: …”it sure seems like the YouTube guys were taking blind stabs at encoding parameters (ie. ‘Hey, let’s set everything to 240 and see what happens!’).”

First Digital Pictures

If Michael can show off the very first pictures from his new digital camera, then so can I… where “new” is roughly July, 2003. I was organizing thousands of digital photos from the last 6 years and found what must be the first pictures from my current digital camera, based on the filename. And wouldn’t you know, the pictures were of felines:

Wide-eyed kitten

It’s all coming back now — I invested in the Canon Powershot S400 back when I was fostering a family of 5 kittens and their mother for the local animal shelter.

Scooter the kitten

So it has come to this– posting cat pictures. Eh, it’s a holiday. Above was Scooter. He was the bravest of the litter. This was feeding time:

Kitten feeding time

As you can plainly see, I’m not a very good photographer. Plus, I had a phenomenal amount of difficulty adjusting to this new camera, which was a substantial feature upgrade from the S100 I had purchased 2 years earlier. Many of my earliest photos can out very blurry or with saturated colors until I learned how the camera expected to be used.