Monthly Archives: October 2005

Digital Black and White

In an earlier post, I pointed at fellow Pixarian Juan Buhler’s awesome photography blog. Unfortunately, I missed our photoclub meeting, but he sent out mail indicating that he uses some of the techniques listed in Digital Black and White to get his spectactular street photos. I’ve actually seen this page before, (thought I might have even blogged it), but haven’t worked on creating the appropriate workflow for Gimp (I’m too cheap to buy Photoshop, and just honest enough not to pirate it :-).

Mars at Opposition

Mars, Octover 21, 2005

I haven’t blogged too much about things having to do with astronomy as of late, but last Friday I took time out of my normal telescope making activities to actually stare through one: actually the 8″ Alvan Clark refractor (nicknamed Leah) that’s at the Chabot Space and Science Center. Mars is currently closing on its closest approach to the earth on October 29-30th, and is currently well placed for observation. The air conditions were slightly foggy but rather still, so I could see lots of good detail on Mars. If you need help identifying features on Mars, you can use the Java Marslet, a cool little applet that shows the features of Mars as they appear through a telescope. An example view (corresponding to what I saw on Friday) appears on the right. I could see just the hint of the polar cap appearing as a very bright white dot near the bottom of the disk, and could easily see Serpentis and Meridiani Margaritfer as horizontal features crossing the disc. Syrtis Major was just coming up over the limb, and could be seen when seeing becomes particularly still. Overall, one of the nicer views of Mars I’ve seen in recent years.

If you get a chance to see Mars through a telescope, take advantage. It’s pretty cool.

Principal says students can’t keep blogs or MySpace profiles

Wow, it’s hard to imagine a more idiotic or wrong-headed school policy than this one. At Pope John XIII Regional High School, principal McHugh decided that students should not have blogs, and have threatened those who oppose the ban with suspension.

The primary impetus behind the ban is to protect students, McHugh said. The Web sites, popular forums for students to blog about their lives and feelings about their teachers and schools, are fertile ground for sexual predators to gather information about children, he said.

Can anyone else spot the irony of this statement? Anyone?

Said EFF attorney Kevin Bankston:

“It’s an incredible overreaction based on an unproven problem,” Bankston said. “If they’re concerned about safety, they could train students in what they should or shouldn’t put online. Kids shouldn’t be robbed of the primary communication tool of their generation.”

Amen.

Cleaning up old video…

While I was encoding videos over the weekend, I wrote a simple little filter to average consecutive frames to produce less noisy versions of title cards. I tested it on 25 frames from the titles of The Vampire Bat.

It looks a little soft because I haven’t worked out the registration, but it nicely eliminated various frame artifacts like dust and scratches. I’ve got the silly idea that relatively simple processing like this can make relatively bad prints such as this one into more attractive prints, if not actually good ones. I’ll have to work on it some more in the future.

Addendum: This might be a good place to start with a more sophisticated version.

The MINIX 3 Operating System

How did I miss this? Minix, the small OS designed by professor Andrew Tanenbaum to teach operating systems concets, is now in its 3.0 revision. From their webpage:

MINIX 1 and 2 were intended as teaching tools; MINIX 3 adds the new goal of being usable as a serious system on resource-limited and embedded computers and for applications requiring high reliability.

Neat. I’ll have to check it out.

Reprogrammable Genesis cartridge

Raphael Assénat created his own reprogrammable cartridge for the Sega Genesis so that he could give a try at writing his own homebrew games. I’ve seen his webpage before, in particular, his experimetns with webcams. Good stuff.

Hardware-wise, the Genesis is kind of a cute computer: It’s got an 8Mhz 68000 processor, 64KB of dedicated video ram, and a separate Z-80 chip to control the sound processor. A veritable super computer compared to the machine I’ve been playing with.

Cartoon for your video iPod

I took one of the Superman cartoons available from archive.org and tried various command line tools to make a version that would play on the iPod video. I seemed to have a bit of trouble getting ffmpeg to write a .mp4 file that Quicktime/iTunes liked, so eventually I used ffmpeg to write a raw .m4v video file, encoded the audio separately with faac, and then used mp4creator, part of the mpeg4ip tools to combine them, hint and optimize them. It seemed to work.

Here’s the tracks in the file…

[fishtank] % mp4info super.mp4
mp4info version 1.3
super.mp4:
Track   Type    Info
1       video   MPEG-4 Simple @ L1, 614.881 secs, 192 kbps, 320x240 @ 29.970027 fps
2       audio   MPEG-4 AAC LC, 614.741 secs, 62 kbps, 48000 Hz
3       hint    Payload MP4V-ES for track 1
4       hint    Payload mpeg4-generic for track 2
 Metadata Tool: mp4creator 1.3

I believe that these are the commands that I ran:

ffmpeg -i superman_the_mechanical_monsters.mpeg -an -vcodec mpeg4 -b 192 -s 320×240 -pass 1 super.m4v
ffmpeg -i superman_the_mechanical_monsters.mpeg -an -vcodec mpeg4 -b 192 -s 320×240 -pass 2 super.m4v
ffmpeg -i superman_the_mechanical_monsters.mpeg -vn super.wav
faac –mpeg-vers 4 -b 64 -o super.aac super.wav
mp4creator -r 29.97 -c super.m4v super.mp4
mp4creator -r 29.97 -c super.aac super.mp4
mp4creator -hint=1 super.mp4
mp4creator -hint=2 super.mp4
mp4creator -optimize super.mp4

The net result: this video file. It’s a little blocky, but should play well on your video ipod. Let me know how it works out.

Could a new browser get you switch?

I like Firefox.  It works well, robustly supports web standards, and generally is just a lot more pleasant than using Internet Explorer.   Given that I’m happy with Firefox, what could make me switch to a new browser?  

Maybe Flock has the right idea: integrate a wide number of web services (such as blogging and tagging) in a solid, open browser.   I’m trying to post this to my blog using the facilities built into flock as we speak.  Seems very smooth and well done.  I’m going to be keeping my eye on this one.

archive.org for your video iPod needs

Just in case you got tired of showing off Desparate Housewives on your new video ipod, you can surf on over to archive.org and download some of their feature films to help fill those gigabytes. Some worthwhile classics: Night of the Living Dead, film noir classic D.O.A. and Flash Gordon Conquers the Universe. Simply download the 256kb MPEG 4 version, sync them to your ipod and voila! Entertainment.

(Oh, these files also play just as well in the Core Pocket Media Player I mentioned in the previous post).

Enjoy.

Update: Further testing reveals that while the videos from archive.org work, the audio is occasionally plagued by intermittent static bursts. Some incompatibility between mpeg audio codecs? More exploration is clearly needed.

You can take it with you

Well, my wife and I are coming up on our 11th anniversary of our first date, an important holiday which she leveraged to get me to buy her a new video iPod, which she’s had for a couple of days. Expect a podcast in the next few days (recorded not in my car, but in BrainWagon Studios, aka my dining room, but with decent mics and my mixer setup) to relay her impressions of the little gadget, and the results of our efforts to load various kinds of free video media on it.

In the mean time, not to be left out, I downloaded the Core Pocket Media Player for my Dell Axim x50v, and I must admit, this is one slick program. It allows playing of MPEG-1, MPEG-4, DivX and MJPEG video files on your Pocket PC, along with MP3 audio and Ogg Vorbis files. It’s released under the GPL, and free, so download and enjoy! They apparently even have a version for Smartphones, so I’ll be checking that out before our next podcast.

Update: I tried out the SmartPhone version too. It works well, albeit not as smoothly as the version for the Pocket PC (much lower power computer in the phone). Good stuff!

live-f1, a good hack

Scott Remnant is a bit of a Formula-1 buff, and so ran one of those cool Java applets that news agencies provide to keep track of race results in real time. But the problem was, the applet sucked (bad interface, the fonts were too small, you know the drill). So, he cleverly ran tcpdump to figure out what was going over the wire and wrote his own version. Rockin’.

I need such a gadget to monitor baseball games too. Maybe next year I’ll give it a try.

World Series: White Sox v. Astros

Well, the table has been set, and it’s going to be the White Sox vs. the Astros in the World Series beginning Saturday. Brad Lidge should send Oswalt flowers: if Oswalt blew the game, we’d be looking at a nerve wracking game seven, and it could have been bad. Instead, the Astros win their first NLCS pennant and a trip to the Series. All is forgotten.

White Sox / AstrosAll over the radio I’ve been hearing that this is going to be a total ratings fiasco: that nobody cares if either of these teams wins, but I think that’s silly. Baseball isn’t baseball only when the Yankees or the Red Sox are playing. These teams won the right to play in the Series, and despite the fact that I picked neither to advance, I think the matchups are going to be pretty interesting. It looks like it will be Roger Clemens (boo, hiss!) for the Astros in Game 1, and despite my dislike for Clemens, you have to give the guy some credit: he’s 13-8 with an astonishing 1.87 ERA in 2005. That’s just wicked. Game 2 will feature Andy Pettitte. On paper he doesn’t look as strong, but he’s got good stuff. Lidge (despite giving up the hit to Pujols, arguably the best bat in the NL) will be strong in relief. The White Sox had four complete game efforts in a row in the ALCS, going with Buehrle, Garland, Garcia and Contreras. That’s… just freaking amazing.

If there is one downside to the postseason so far, it’s the really questionable officiating. In virtually every game I’ve seen so far, there has been at least one highly questionable call by an umpire. Can we get some decent officiating for the Series?

I’m heating up the skillet to make some of my faux Buffalo Wings and some blue cheese dip. I’ll be good to go on Saturday. And I think I’m going to root for… The White Sox. Sorry Roger, just don’t like you, and I like the idea that the White Sox could win their first Series since 1917. Or maybe it’s just the idea that if the Sox lead, the ghost of Shoeless Joe will materialize in the White Sox dugout.

I love October baseball.