People keep showing up on GIMP's IRC channels and asking about
JPEG 2000 support. There was a Summer
"Wavelet" project last summer which implemented JPEG 2000 support
(among other things) but no one ever seems to know where to find it.
So I asked Simon, who was the mentor for that project. Turns out
he had tarballs, but didn't think it was appropriate to link them
from his own site, especially as they were somewhat tricky to
The consensus among the developers was that it would be nice to
have jp2 and the other wavelet plug-ins available on the
GIMP Plug-in Registry.
So I fiddled with them, fixed a couple of Makefile issues,
added READMEs with author credit and building instructions,
and uploaded them to the registry. The plug-ins are:
- JPEG 2000 support
- A noise removal plug-in
- Inverse halftoning -- remove halftones from printed images.
I haven't actually used these plug-ins (couldn't find a JPEG2k file
to test) -- I just wanted to help
make them available for people who need them.
While I was at it I updated my vastly out-of-date registry
entries for Pandora and added an entry for my label/business card
[ 13:54 Nov 23, 2006
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I just tried Ubuntu's newest release, "Edgy
Eft", on the laptop (my trusty if aging Vaio SR17).
I used the "xubuntu" variant, in order to try out their lighter
weight xfce-based desktop.
So far it looks quite good.
But the installation process involved
quite a few snags: here follows an account of the various workarounds
I needed to get it up and running.
Live CD Problems
First, I tried to use the live CD, since I've heard it has a nice
installer. But it failed during the process of bringing up X, and
dumped me into me a console screen with an (initramfs) prompt.
I thought I had pretty good Linux creds, but I have to confess
I don't know what to do with an (initramfs) prompt; so I gave up
and switched to the install CD. Too bad! I was so impressed with
Ubuntu's previous live CDs, which worked well on this machine.
Guessing Keyboard Layout
Early on, the installer gives you the option to let it guess your
keyboard layout. Don't let it! What this does is subject you
to a seemingly infinite list of questions like:
Does your keyboard have a squiggle key?
where each squiggle
is a different garbled, completely illegible
character further mangled by the fact that the installer is running at
a resolution not native to the current LCD display. After about 15 of
these you just give up and start hitting return hoping it will end
soon -- but it doesn't, so eventually you give up and try ctl-alt-del.
But that doesn't work either. Pulling the power cord and starting over
seems to be the only answer. Everyone I've talked to who's installed
Edgy has gone through this exact experience and we all had a good
laugh about it. Come to think of it, go ahead and say yes to the
keyboard guesser, just so you can chuckle about it with the rest of us.
Once I rebooted and said no to the keyboard guesser, it asked three or
four very straightforward questions about language, and the rest
of the installation went smoothly. Of course it whined about not
seeing a network, and it whined about my not wanting it to overwrite
my existing /boot, and it whined about something to do with free
space on my ext3 partitions (set up by a previous breezy install),
but it made it through.
X Hangs on the Savage
On the first reboot after installation, it
hung while trying to start X -- blank screen, no keyboard
response, and I needed to pull the plug. I was prepared for that
(longstanding bug 41340)
so I immediately suspected dri. I booted from another partition and
removed the dri lines from /etc/X11/xorg.conf,
which fixed the problem.
Configuring the Network
Now I was up and running on Xubuntu Edgy.
Next I needed to configure the network (since the installer won't do
it: this machine only has one pcmcia slot, so it can't have
a CDROM drive and a network card installed at the same time).
I popped in the network card (a 3com 3c59x cardbus card) and waited
expectantly for something to happen.
Nada. So I poked around and found the network configuration tool in
the menus, set up my IP and DNS and all that, and looked in vain for
a "start network" or "enable card" or some similar button that would
perform an ifup eth0.
Nada again. Eventually I gave up, called up a terminal, and ran
ifup eth0, which worked fine.
Which leads me to ask:
Given that Ubuntu is so committed to automatic hardware detection that
it forces you to run hal, which spawns large numbers of daemons that
poll all your disks a couple of times a second -- why can't it notice
the insertion of a cardbus networking card?
And configure it in some easy way without requiring the user to know
about terminals and networking commands?
Ubuntu Still Wins for Suspend and Hibernate
Around this point I tested suspend and hibernate. They both worked
beautifully out of the box, with no additional twiddling
needed. Ubuntu is still the leader in suspending.
sudo: Timestamp Woes
Somewhere during these package management games, I lost the ability
to sudo: it complained "Timestamp too far in the future", without
telling me which file's timestamp was wrong so that I could fix it.
Googling showed that lots of other people were having the
same problem with Edgy, and found an answer: use the GUI Time and
Date tool to set the time to something farther in the future than
the timestamp sudo was complaining about, then run sudo -k to do
some magic that resets the timestamp. Then you can set the time back
to where it belongs. Why does this happen? No one seems to know, but
that's the fix.
(I found some discussion in
vim isn't vim?
I restored my normal user account, logged in as myself with my normal
fvwm environment, and went to edit (with vim) a few files. Every time,
"E319: Sorry, the command is not available in this version: syntax on"
after which I could edit the file normally. Eventually I googled to
the answer, which is très
bizarre: by default,
is installed but vim
is not. There's a binary
named vim, and a package which seems to be vim, but it isn't vim.
Installing the package named vim
gives you a vim that
understands "syntax on" without complaining.
That's the list. Edgy is up and running now, and looks pretty good.
The installer definitely has some rough edges, and I hope my
workarounds are helpful to someone ... but the installer is only
a tiny part of the OS, something you run only once or twice.
So don't let the rough installer stop you from installing Edgy and
trying it out. I know I look forward to using it.
[ 20:30 Nov 20, 2006
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Mercury transited the sun today. The weather forecast predicted
rain, and indeed, I awoke this morning to a thick overcast which
soon turned to drizzle. But miraculously, ten minutes before the
start of the transit the sky cleared, and we were able to see
the whole thing, all five hours of it (well, we weren't watching
for the whole five hours -- the most interesting parts are the
beginning and end).
I had plenty of practice with solar observing yesterday,
showing the sun to a group of middle school girls as part of
an astronomy workshop.
This is organized by the AAUW, the same group that runs the annual
summer science girls' camps. (The Stanford Tech Trek has a star
party, which is how I got involved with this group.)
It's the second year I've done the astronomy workshop for
them; this year went pretty smoothly and everybody seemed to
have a good time observing the sun, simulating moon phases,
learning about the Doppler effect and plotting relative distances
of the planets on a road map.
But what I really wanted to write about was the amazing video
shown by last weekend's SJAA speaker, Dr. Ivan Linscott of Stanford.
As one of the team members on the New Horizons mission to Pluto,
he was telling us about Pluto's tenuous atmosphere. There isn't a
lot of information on Pluto's atmosphere yet, but one of the goals of
New Horizons is to take readings as Pluto occults the sun to
see how sunlight is refracted through Pluto's atmosphere.
But that's no problem: it turns out we've already
done more challenging occultation studies than that.
Back in December 2001, Titan occulted a binary star, and
researchers using Palomar's Adaptive Optics setup got a
spectacular video of the stars being refracted through Titan's
atmosphere as the occultation progresses.
This is old news, of course, but most of us hadn't seen it before
and everyone was blown away. Remember, this is a video from Earth,
of the atmosphere of a moon of Saturn, something most Earth-based
telescopes would have trouble even resolving as a disk.
the Titan occultation video here.
[ 23:38 Nov 08, 2006
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